Recommendations for push mower motor?

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Recommendations for push mower motor?

Michael Ross
I have an old simple ICE push mower, that might be worth converting.

Can anyone recommend the sort of motor I should look for?

Re-purposing a motor would be nice.

I would use LFP batteries.

What about the shock of the blade hitting something nearly immobile? That
is a lot of shock that small engines are able to handle - special
consideration in the regard with electric motors?

Mounting the blade seem non-trivial?  Hints?

Thanks!

I just saw a Li ion powered mower on line for $500.  supposed to run for 45
minutes and charge back in 30.  That sounds like a practical target.  48V
pack.  Weighs 62lb.

Any thought on this side of the equation?  36V?  60V?  Capacity needed to
go 45 minutes?

--
Don't believe everything you read on the Internet - Abraham Lincoln

A public-opinion poll is no substitute for thought.
*Warren Buffet*

Michael E. Ross
(919) 550-2430 Land
(919) 576-0824 <https://www.google.com/voice/b/0?pli=1#phones> Google Phone
(919) 631-1451 Cell
(919) 513-0418 Desk

[hidden email]
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Re: Recommendations for push mower motor?

Cal Frye
I'm on my second Black and Decker push mower, corded type. I have a
small lawn, so avoiding running over the cord is not a major problem. I
won't advise on motor or batteries, but I can say B&D has a plastic shim
in the stack of washers holding the blade to the motor shaft. Said shim
has raised edges which grip either side of the blade, and an opposing
pair of edges which grip in turn a keyed, square washer above the blade.
This square washer is driven by the motor, and the blade is driven by
the plastic shim. Hit too hard an obstacle, and the plastic edges shear
off and the blade rotates freely.

This is effective, but is also a wear point, and I've learned to buy the
shims by the half-dozen. My eyes don't always find the rocks in the yard
before the blade does :-(

Best regards,
-- Cal Frye, www.calfrye.com
/Be an Internet Sceptic/  Stop. Think. Connect.
www.stopthinkconnect.org - Be at least as safe on the
Internet as you are crossing the street!

"I sincerely believe that banking establishments are more dangerous than
standing armies." -- Thomas Jefferson, letter to John Taylor.



> Michael Ross <mailto:[hidden email]>
> April 28, 2014 12:58 PM
> I have an old simple ICE push mower, that might be worth converting.
>
> ...

> What about the shock of the blade hitting something nearly immobile? That
> is a lot of shock that small engines are able to handle - special
> consideration in the regard with electric motors?
>
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Re: Recommendations for push mower motor?

Lee Hart
In reply to this post by Michael Ross
Michael Ross wrote:
> I have an old simple ICE push mower, that might be worth converting.

I've done some conversions, both for myself and for friends.

A standard ICE push mower, or corded electric mower is easy to convert;
but likely to be less than satisfactory to use. The weight of the
batteries will make it a bear to push around. You'd want to use better
wheels, and that gets to be a lot of work to change.

I converted a corded electric mower to battery by adding 60 2v 2.5ah
lead-acid "D" cells. They were packaged into a donut-shaped box that sat
around the existing 120vdc motor. The stock on/off switch operated a big
relay that actually switched the motor. *Don't* use the stock switch to
switch DC to the motor! It will fail almost immediately!

The batteries gave me a mowing time of 15-20 minutes. That was kind of
short, but kept the mower from being too heavy.

A treadmill motor is a reasonable choice with a high voltage battery
pack. They typically draw 5-15 amps. You will need at least 48v for
reasonable speed.

I've also converted small riding mowers. They have the advantage of more
room for batteries, and thus longer mowing times. They can also carry
the weight better. The electric motor doesn't need to be even *remotely*
as much horsepower as they advertise for ICE engines. We converted a
Wheel Horse garden tractor where the 12hp gas engine was replaced with a
1.5hp 36v electric motor. The electric was faster, and had more mowing
power than the ICE.

Avoid mowers and tractors with hydrostatic drives. They are woefully
inefficient. Get one with a mechanical transmission.

On the blade hitting rocks: Copy the same setup they use on the ICE.
They always have some kind of clutch setup so if the blade hits
something, it can instantly stop while the clutch slips. Usually, the
clutch is nothing but a big bolt that pinches the blade between a pair
of friction washers.

Golf carts and small industrial vehicles are common sources of electric
24v to 48v DC motors.

You usually don't need a speed controller. With a PM motor, all you need
is an on/off switch. A "start" switch that puts a resistor in series
with the motor for starting can also help reduce the starting current surge.

--
If we knew what we were doing, it wouldn't be called research, would it?
        -- Albert Einstein
--
Lee Hart's EV projects are at http://www.sunrise-ev.com/LeesEVs.htm
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Re: Recommendations for push mower motor?

Chris Tromley
On Mon, Apr 28, 2014 at 2:01 PM, Lee Hart <[hidden email]> wrote:

> On the blade hitting rocks: Copy the same setup they use on the ICE. They
> always have some kind of clutch setup so if the blade hits something, it
> can instantly stop while the clutch slips. Usually, the clutch is nothing
> but a big bolt that pinches the blade between a pair of friction washers.
>
> My last experience with an ICE mower (long ago) had a soft metal
square-section key between the blade hub and the shaft.  Hit a rock and
you'd shear the key before anything bent.  Made for kind of a hassle to get
it running again (a trip to the mower repair shop for the special soft
key), but it was cheaper to manufacture than the friction washer approach.

I'm a big fan of friction washers.  The three mower motors on my electric
tractor mount the blades this way.  I've hit lots of stuff and never had a
problem.

Chris
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Re: Recommendations for push mower motor?

Peter Eckhoff
In reply to this post by Cal Frye
Hello Mike,

I'll second what Cal is saying below.  To get the nut off, you have to
place a wrench on the nut and "impact" it until the nut loosens.  I
would **not** use a compressed air impactor tool.  I use my fist.  Be
careful because everything is free wheeling.  If you leave your knuckles
in the path of the blade, your knuckles are going to get whacked.  There
is no other place to place another wrench unless you weld a nut to the
top of the motor shaft.

Like Cal, I keep a set of several "small plastic blade insulators" on
hand which is how they are described in the User's Manual.  The word
"insulator" may seem like a misnomer but it is to "insulate" the shock
of hitting a rock from damaging the armature.

I converted a corded B&D to cordless.  It uses 9 - 5 amphr 12 volt LA
AGMs to power the mower.  It is enough to do a 7K square foot lawn.  
What used to take me 1.5 hours to do when corded, now takes about 45
minutes.

I use a 1.3 amphr AGM for the tripping a small contactor.  This battery
goes down faster than the pack.  I would use about a 2 amphr battery for
each hour the contactors are tripped.  That should give you plenty of
cushion.

I wrote a two part article for the Electric Auto Association's Current
Events magazine.  I have the submittals in PDF format. The B&D motors
are DC universal motors that operate at 120 volts.  The corded version
has a full rectifier bridge on a little heat sink.  It was mainly a
rewiring job to bypass the rectifier.

I think the AGMs are the wrong type of battery for this project.
Normally, when not cutting the lawn, the motor consumes about 4 amps.  
When cutting thick grass, the motor consumes about 8 amps. It can spike
to 10 amps in real thick grass or when the mower clogs up in thick grass.

I have been contemplating upgrading this mower to Lithium.  A set of 40
- 3.2 volt 10 amphr would be about right for an hour's worth of cutting
and still have some reserve.  I saw an ad for Shorai 12Volt 12 Amphr
batteries  for $117 each and they weigh about 1.7 pounds.  My 5.0 amphr
batteries weigh 3.5 pounds each for an added weight (starter + pack
support + contactor) of 35 pounds onto a mower that weighs 47 pounds for
a total of around 82 pounds.  This is about the weight of an ICE push
mower.  Twelve Shorai batteries would be around 20 pounds.  The mower
would be lighter and so would your wallet of $1400 plus shipping.

I have thought about purchasing 4 - 100 amphr CALB batteries and then
use a converter to step up the voltage to 120 volts.  At an efficiency
of 85%, the amphrs to the motor would be about 8.5.  I am not sure if a
converter could handle that much amperage.  I was going to do some more
homework before asking the experts here. Four CALB batteries would be
about 600 dollars and a converter would run in the lower several
hundreds.  The savings would be substantial but I am not sure if the
electronics would handle the load.

The other thought would be to run the 4 CALBs into an inverter and leave
the rectifier bridge intact.  The inefficiency of the inverter plus the
inefficiency of the rectifier bridge would likely sap the pack of a lot
of useful energy.  I think this would be a nonstarter.

I know of someone using a self contained electric mower.  You might want
to shoot him an email at theadm *A*T* AOL.  If you are in the RTP area,
we are both "local".

Everyone else I see running an electric mower are running with a cord.  
If you want me to, I will ask my neighbors their brand and opinions.

On 4/28/2014 1:27 PM, Cal Frye wrote:

> I'm on my second Black and Decker push mower, corded type. I have a
> small lawn, so avoiding running over the cord is not a major problem. I
> won't advise on motor or batteries, but I can say B&D has a plastic shim
> in the stack of washers holding the blade to the motor shaft. Said shim
> has raised edges which grip either side of the blade, and an opposing
> pair of edges which grip in turn a keyed, square washer above the blade.
> This square washer is driven by the motor, and the blade is driven by
> the plastic shim. Hit too hard an obstacle, and the plastic edges shear
> off and the blade rotates freely.
>
> This is effective, but is also a wear point, and I've learned to buy the
> shims by the half-dozen. My eyes don't always find the rocks in the yard
> before the blade does :-(
>
> Best regards,
> -- Cal Frye, www.calfrye.com
> /Be an Internet Sceptic/  Stop. Think. Connect.
> www.stopthinkconnect.org - Be at least as safe on the
> Internet as you are crossing the street!
>
> "I sincerely believe that banking establishments are more dangerous than
> standing armies." -- Thomas Jefferson, letter to John Taylor.
>
>
>
>> Michael Ross <mailto:[hidden email]>
>> April 28, 2014 12:58 PM
>> I have an old simple ICE push mower, that might be worth converting.
>>
>> ...
>> What about the shock of the blade hitting something nearly immobile? That
>> is a lot of shock that small engines are able to handle - special
>> consideration in the regard with electric motors?
>>
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Re: Recommendations for push mower motor?

Michael Ross
I have another battery from these people that seems just fine (after taking
it apart to see inside)

http://www.aliexpress.com/store/product/24V-40AH-LiFePO4-Battery-Pack-Electric-Bicycle-electric-Scooter-bicycle-E-Bike-Lithium-Ion-Long-life/328001_771068114.html

This one is 24V 40Ah LFP and weighs 9kg.  $500 including shipping BMS and
charger. 3 to 7 day delivery and the met that. These that 18650 cells with
welded straps for conducting the juice.

I think I will try to get a used 24V B&D instead of reworking my old bottom
of the line MTD.

I think my wife would love to have an electric mower.  She hates asking me
to start them for her.  It would be nice not having all the oil checking
and filling,   And as the current mower works - the rod knocking and
smoking.  We have an acre of mostly flat yard - 40Ah would go a long ways
and the charge time is about 2 hours.


On Mon, Apr 28, 2014 at 3:25 PM, Peter Eckhoff <[hidden email]> wrote:

> Hello Mike,
>
> I'll second what Cal is saying below.  To get the nut off, you have to
> place a wrench on the nut and "impact" it until the nut loosens.  I would
> **not** use a compressed air impactor tool.  I use my fist.  Be careful
> because everything is free wheeling.  If you leave your knuckles in the
> path of the blade, your knuckles are going to get whacked.  There is no
> other place to place another wrench unless you weld a nut to the top of the
> motor shaft.
>
> Like Cal, I keep a set of several "small plastic blade insulators" on hand
> which is how they are described in the User's Manual.  The word "insulator"
> may seem like a misnomer but it is to "insulate" the shock of hitting a
> rock from damaging the armature.
>
> I converted a corded B&D to cordless.  It uses 9 - 5 amphr 12 volt LA AGMs
> to power the mower.  It is enough to do a 7K square foot lawn.  What used
> to take me 1.5 hours to do when corded, now takes about 45 minutes.
>
> I use a 1.3 amphr AGM for the tripping a small contactor.  This battery
> goes down faster than the pack.  I would use about a 2 amphr battery for
> each hour the contactors are tripped.  That should give you plenty of
> cushion.
>
> I wrote a two part article for the Electric Auto Association's Current
> Events magazine.  I have the submittals in PDF format. The B&D motors are
> DC universal motors that operate at 120 volts.  The corded version has a
> full rectifier bridge on a little heat sink.  It was mainly a rewiring job
> to bypass the rectifier.
>
> I think the AGMs are the wrong type of battery for this project. Normally,
> when not cutting the lawn, the motor consumes about 4 amps.  When cutting
> thick grass, the motor consumes about 8 amps. It can spike to 10 amps in
> real thick grass or when the mower clogs up in thick grass.
>
> I have been contemplating upgrading this mower to Lithium.  A set of 40 -
> 3.2 volt 10 amphr would be about right for an hour's worth of cutting and
> still have some reserve.  I saw an ad for Shorai 12Volt 12 Amphr batteries
>  for $117 each and they weigh about 1.7 pounds.  My 5.0 amphr batteries
> weigh 3.5 pounds each for an added weight (starter + pack support +
> contactor) of 35 pounds onto a mower that weighs 47 pounds for a total of
> around 82 pounds.  This is about the weight of an ICE push mower.  Twelve
> Shorai batteries would be around 20 pounds.  The mower would be lighter and
> so would your wallet of $1400 plus shipping.
>
> I have thought about purchasing 4 - 100 amphr CALB batteries and then use
> a converter to step up the voltage to 120 volts.  At an efficiency of 85%,
> the amphrs to the motor would be about 8.5.  I am not sure if a converter
> could handle that much amperage.  I was going to do some more homework
> before asking the experts here. Four CALB batteries would be about 600
> dollars and a converter would run in the lower several hundreds.  The
> savings would be substantial but I am not sure if the electronics would
> handle the load.
>
> The other thought would be to run the 4 CALBs into an inverter and leave
> the rectifier bridge intact.  The inefficiency of the inverter plus the
> inefficiency of the rectifier bridge would likely sap the pack of a lot of
> useful energy.  I think this would be a nonstarter.
>
> I know of someone using a self contained electric mower.  You might want
> to shoot him an email at theadm *A*T* AOL.  If you are in the RTP area, we
> are both "local".
>
> Everyone else I see running an electric mower are running with a cord.  If
> you want me to, I will ask my neighbors their brand and opinions.
>
>
> On 4/28/2014 1:27 PM, Cal Frye wrote:
>
>> I'm on my second Black and Decker push mower, corded type. I have a
>> small lawn, so avoiding running over the cord is not a major problem. I
>> won't advise on motor or batteries, but I can say B&D has a plastic shim
>> in the stack of washers holding the blade to the motor shaft. Said shim
>> has raised edges which grip either side of the blade, and an opposing
>> pair of edges which grip in turn a keyed, square washer above the blade.
>> This square washer is driven by the motor, and the blade is driven by
>> the plastic shim. Hit too hard an obstacle, and the plastic edges shear
>> off and the blade rotates freely.
>>
>> This is effective, but is also a wear point, and I've learned to buy the
>> shims by the half-dozen. My eyes don't always find the rocks in the yard
>> before the blade does :-(
>>
>> Best regards,
>> -- Cal Frye, www.calfrye.com
>> /Be an Internet Sceptic/  Stop. Think. Connect.
>> www.stopthinkconnect.org - Be at least as safe on the
>> Internet as you are crossing the street!
>>
>> "I sincerely believe that banking establishments are more dangerous than
>> standing armies." -- Thomas Jefferson, letter to John Taylor.
>>
>>
>>
>>  Michael Ross <mailto:[hidden email]>
>>> April 28, 2014 12:58 PM
>>> I have an old simple ICE push mower, that might be worth converting.
>>>
>>> ...
>>> What about the shock of the blade hitting something nearly immobile? That
>>> is a lot of shock that small engines are able to handle - special
>>> consideration in the regard with electric motors?
>>>
>>>  -------------- next part --------------
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>> _______________________________________________
>> UNSUBSCRIBE: http://www.evdl.org/help/index.html#usub
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>> group/NEDRA)
>>
>>
>>
> _______________________________________________
> UNSUBSCRIBE: http://www.evdl.org/help/index.html#usub
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> For EV drag racing discussion, please use NEDRA (http://groups.yahoo.com/
> group/NEDRA)
>
>


--
Put this question to yourself: should I use everyone else to attain
happiness, or should I help others gain happiness?
*Dalai Lama *

Tell me what it is you plan to do
With your one wild and precious life?
Mary Oliver, "The summer day."

To invent, you need a good imagination and a pile of junk.
Thomas A. Edison<http://www.brainyquote.com/quotes/quotes/t/thomasaed125362.html>

A public-opinion poll is no substitute for thought.
*Warren Buffet*

Michael E. Ross
(919) 550-2430 Land
(919) 576-0824 <https://www.google.com/voice/b/0?pli=1#phones> Google Phone
(919) 631-1451 Cell
(919) 513-0418 Desk

[hidden email]
<[hidden email]>
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Re: Recommendations for push mower motor?

Mark Hastings
I have a cordless B&D that i changed out to use 24v 20ah thundersky batts a
few seasons ago and shared the battery for a while on my recumbent for
assist.  It certainly won't do my new 2+ acres but was cheap with dead
batteries off of craigslist and the lighter batteries made it tolerable to
push in the hundred degree heat. All it took was remove the old battery,
connect the new one and I lazily just popped it out to take to the workshop for
charging instead of making it permanent since it was intended to be a dual
use battery.

On Monday, April 28, 2014, Michael Ross <[hidden email]> wrote:

> I have another battery from these people that seems just fine (after taking
> it apart to see inside)
>
>
> http://www.aliexpress.com/store/product/24V-40AH-LiFePO4-Battery-Pack-Electric-Bicycle-electric-Scooter-bicycle-E-Bike-Lithium-Ion-Long-life/328001_771068114.html
>
> This one is 24V 40Ah LFP and weighs 9kg.  $500 including shipping BMS and
> charger. 3 to 7 day delivery and the met that. These that 18650 cells with
> welded straps for conducting the juice.
>
> I think I will try to get a used 24V B&D instead of reworking my old bottom
> of the line MTD.
>
> I think my wife would love to have an electric mower.  She hates asking me
> to start them for her.  It would be nice not having all the oil checking
> and filling,   And as the current mower works - the rod knocking and
> smoking.  We have an acre of mostly flat yard - 40Ah would go a long ways
> and the charge time is about 2 hours.
>
>
> On Mon, Apr 28, 2014 at 3:25 PM, Peter Eckhoff <[hidden email]> wrote:
>
> > Hello Mike,
> >
> > I'll second what Cal is saying below.  To get the nut off, you have to
> > place a wrench on the nut and "impact" it until the nut loosens.  I would
> > **not** use a compressed air impactor tool.  I use my fist.  Be careful
> > because everything is free wheeling.  If you leave your knuckles in the
> > path of the blade, your knuckles are going to get whacked.  There is no
> > other place to place another wrench unless you weld a nut to the top of
> the
> > motor shaft.
> >
> > Like Cal, I keep a set of several "small plastic blade insulators" on
> hand
> > which is how they are described in the User's Manual.  The word
> "insulator"
> > may seem like a misnomer but it is to "insulate" the shock of hitting a
> > rock from damaging the armature.
> >
> > I converted a corded B&D to cordless.  It uses 9 - 5 amphr 12 volt LA
> AGMs
> > to power the mower.  It is enough to do a 7K square foot lawn.  What used
> > to take me 1.5 hours to do when corded, now takes about 45 minutes.
> >
> > I use a 1.3 amphr AGM for the tripping a small contactor.  This battery
> > goes down faster than the pack.  I would use about a 2 amphr battery for
> > each hour the contactors are tripped.  That should give you plenty of
> > cushion.
> >
> > I wrote a two part article for the Electric Auto Association's Current
> > Events magazine.  I have the submittals in PDF format. The B&D motors are
> > DC universal motors that operate at 120 volts.  The corded version has a
> > full rectifier bridge on a little heat sink.  It was mainly a rewiring
> job
> > to bypass the rectifier.
> >
> > I think the AGMs are the wrong type of battery for this project.
> Normally,
> > when not cutting the lawn, the motor consumes about 4 amps.  When cutting
> > thick grass, the motor consumes about 8 amps. It can spike to 10 amps in
> > real thick grass or when the mower clogs up in thick grass.
> >
> > I have been contemplating upgrading this mower to Lithium.  A set of 40 -
> > 3.2 volt 10 amphr would be about right for an hour's worth of cutting and
> > still have some reserve.  I saw an ad for Shorai 12Volt 12 Amphr
> batteries
> >  for $117 each and they weigh about 1.7 pounds.  My 5.0 amphr batteries
> > weigh 3.5 pounds each for an added weight (starter + pack support +
> > contactor) of 35 pounds onto a mower that weighs 47 pounds for a total of
> > around 82 pounds.  This is about the weight of an ICE push mower.  Twelve
> > Shorai batteries would be around 20 pounds.  The mower would be lighter
> and
> > so would your wallet of $1400 plus shipping.
> >
> > I have thought about purchasing 4 - 100 amphr CALB batteries and then use
> > a converter to step up the voltage to 120 volts.  At an efficiency of
> 85%,
> > the amphrs to the motor would be about 8.5.  I am not sure if a converter
> > could handle that much amperage.  I was going to do some more homework
> > before asking the experts here. Four CALB batteries would be about 600
> > dollars and a converter would run in the lower several hundreds.  The
> > savings would be substantial but I am not sure if the electronics would
> > handle the load.
> >
> > The other thought would be to run the 4 CALBs into an inverter and leave
> > the rectifier bridge intact.  The inefficiency of the inverter plus the
> > inefficiency of the rectifier bridge would likely sap the pack of a lot
> of
> > useful energy.  I think this would be a nonstarter.
> >
> > I know of someone using a self contained electric mower.  You might want
> > to shoot him an email at theadm *A*T* AOL.  If you are in the RTP area,
> we
> > are both "local".
> >
> > Everyone else I see running an electric mower are running with a cord.
>  If
> > you want me to, I will ask my neighbors their brand and opinions.
> >
> >
> > On 4/28/2014 1:27 PM, Cal Frye wrote:
> >
> >> I'm on my second Black and Decker push mower, corded type. I have a
> >> small lawn, so avoiding running over the cord is not a major problem. I
> >> won't advise on motor or batteries, but I can say B&D has a plastic shim
> >> in the stack of washers holding the blade to the motor shaft. Said shim
> >> has raised edges which grip either side of the blade, and an op--
> Put this question to yourself: should I use everyone else to attain
> happiness, or should I help others gain happiness?
> *Dalai Lama *
>
> Tell me what it is you plan to do
> With your one wild and precious life?
> Mary Oliver, "The summer day."
>
> To invent, you need a good imagination and a pile of junk.
> Thomas A. Edison<
> http://www.brainyquote.com/quotes/quotes/t/thomasaed125362.html>
>
> A public-opinion poll is no substitute for thought.
> *Warren Buffet*
>
> Michael E. Ross
> (919) 550-2430 Land
> (919) 576-0824 <https://www.google.com/voice/b/0?pli=1#phones> Google
> Phone
> (919) 631-1451 Cell
> (919) 513-0418 Desk
>
> [hidden email] <javascript:;>
> <[hidden email] <javascript:;>>
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Re: Recommendations for push mower motor?

Cor van de Water
In reply to this post by Michael Ross
I agree on starting with a "needs new battery" type cordless mower.
I picked up a 36V WORX WG788 which also is supposed to have
"IntelliCut" which appears to be a hall sensor and magnet on the back
of the motor's axle, so the controller can regulate the power to the
motor for constant mowing speed, no matter the load.
Unfortunately this controller let the smoke out and I have considered
getting a cheap 36V eBike controller as well as just using the PM
motor directly on a new pack, but found that the inrush current is
quite significant so a controller or current limit of sorts is going to
be needed to avoid blowing things up.
However, my yard is so small that for the time being, I can easily
mow it with a real (reel-type) push mower, so the e-mower remains one
of the many projects waiting for time or another loving home.
I checked and the PM motor is fine, in case anybody is interested,
it is located in the south of the SF bay area, aka Silicon Valley.

Cor van de Water
Chief Scientist
Proxim Wireless Corporation http://www.proxim.com
Email: [hidden email] Private: http://www.cvandewater.info
Skype: cor_van_de_water Tel: +1 408 383 7626


-----Original Message-----
From: [hidden email] [mailto:[hidden email]] On
Behalf Of Michael Ross
Sent: Monday, April 28, 2014 12:46 PM
To: Electric Vehicle Discussion List
Subject: Re: [EVDL] Recommendations for push mower motor?

I have another battery from these people that seems just fine (after
taking
it apart to see inside)

http://www.aliexpress.com/store/product/24V-40AH-LiFePO4-Battery-Pack-El
ectric-Bicycle-electric-Scooter-bicycle-E-Bike-Lithium-Ion-Long-life/328
001_771068114.html

This one is 24V 40Ah LFP and weighs 9kg.  $500 including shipping BMS
and
charger. 3 to 7 day delivery and the met that. These that 18650 cells
with
welded straps for conducting the juice.

I think I will try to get a used 24V B&D instead of reworking my old
bottom
of the line MTD.

I think my wife would love to have an electric mower.  She hates asking
me
to start them for her.  It would be nice not having all the oil checking
and filling,   And as the current mower works - the rod knocking and
smoking.  We have an acre of mostly flat yard - 40Ah would go a long
ways
and the charge time is about 2 hours.


On Mon, Apr 28, 2014 at 3:25 PM, Peter Eckhoff <[hidden email]>
wrote:

> Hello Mike,
>
> I'll second what Cal is saying below.  To get the nut off, you have to
> place a wrench on the nut and "impact" it until the nut loosens.  I
would
> **not** use a compressed air impactor tool.  I use my fist.  Be
careful
> because everything is free wheeling.  If you leave your knuckles in
the
> path of the blade, your knuckles are going to get whacked.  There is
no
> other place to place another wrench unless you weld a nut to the top
of the
> motor shaft.
>
> Like Cal, I keep a set of several "small plastic blade insulators" on
hand
> which is how they are described in the User's Manual.  The word
"insulator"
> may seem like a misnomer but it is to "insulate" the shock of hitting
a
> rock from damaging the armature.
>
> I converted a corded B&D to cordless.  It uses 9 - 5 amphr 12 volt LA
AGMs
> to power the mower.  It is enough to do a 7K square foot lawn.  What
used
> to take me 1.5 hours to do when corded, now takes about 45 minutes.
>
> I use a 1.3 amphr AGM for the tripping a small contactor.  This
battery
> goes down faster than the pack.  I would use about a 2 amphr battery
for
> each hour the contactors are tripped.  That should give you plenty of
> cushion.
>
> I wrote a two part article for the Electric Auto Association's Current
> Events magazine.  I have the submittals in PDF format. The B&D motors
are
> DC universal motors that operate at 120 volts.  The corded version has
a
> full rectifier bridge on a little heat sink.  It was mainly a rewiring
job
> to bypass the rectifier.
>
> I think the AGMs are the wrong type of battery for this project.
Normally,
> when not cutting the lawn, the motor consumes about 4 amps.  When
cutting
> thick grass, the motor consumes about 8 amps. It can spike to 10 amps
in
> real thick grass or when the mower clogs up in thick grass.
>
> I have been contemplating upgrading this mower to Lithium.  A set of
40 -
> 3.2 volt 10 amphr would be about right for an hour's worth of cutting
and
> still have some reserve.  I saw an ad for Shorai 12Volt 12 Amphr
batteries
>  for $117 each and they weigh about 1.7 pounds.  My 5.0 amphr
batteries
> weigh 3.5 pounds each for an added weight (starter + pack support +
> contactor) of 35 pounds onto a mower that weighs 47 pounds for a total
of
> around 82 pounds.  This is about the weight of an ICE push mower.
Twelve
> Shorai batteries would be around 20 pounds.  The mower would be
lighter and
> so would your wallet of $1400 plus shipping.
>
> I have thought about purchasing 4 - 100 amphr CALB batteries and then
use
> a converter to step up the voltage to 120 volts.  At an efficiency of
85%,
> the amphrs to the motor would be about 8.5.  I am not sure if a
converter
> could handle that much amperage.  I was going to do some more homework
> before asking the experts here. Four CALB batteries would be about 600
> dollars and a converter would run in the lower several hundreds.  The
> savings would be substantial but I am not sure if the electronics
would
> handle the load.
>
> The other thought would be to run the 4 CALBs into an inverter and
leave
> the rectifier bridge intact.  The inefficiency of the inverter plus
the
> inefficiency of the rectifier bridge would likely sap the pack of a
lot of
> useful energy.  I think this would be a nonstarter.
>
> I know of someone using a self contained electric mower.  You might
want
> to shoot him an email at theadm *A*T* AOL.  If you are in the RTP
area, we
> are both "local".
>
> Everyone else I see running an electric mower are running with a cord.
If
> you want me to, I will ask my neighbors their brand and opinions.
>
>
> On 4/28/2014 1:27 PM, Cal Frye wrote:
>
>> I'm on my second Black and Decker push mower, corded type. I have a
>> small lawn, so avoiding running over the cord is not a major problem.
I
>> won't advise on motor or batteries, but I can say B&D has a plastic
shim
>> in the stack of washers holding the blade to the motor shaft. Said
shim
>> has raised edges which grip either side of the blade, and an opposing
>> pair of edges which grip in turn a keyed, square washer above the
blade.
>> This square washer is driven by the motor, and the blade is driven by
>> the plastic shim. Hit too hard an obstacle, and the plastic edges
shear
>> off and the blade rotates freely.
>>
>> This is effective, but is also a wear point, and I've learned to buy
the
>> shims by the half-dozen. My eyes don't always find the rocks in the
yard
>> before the blade does :-(
>>
>> Best regards,
>> -- Cal Frye, www.calfrye.com
>> /Be an Internet Sceptic/  Stop. Think. Connect.
>> www.stopthinkconnect.org - Be at least as safe on the
>> Internet as you are crossing the street!
>>
>> "I sincerely believe that banking establishments are more dangerous
than

>> standing armies." -- Thomas Jefferson, letter to John Taylor.
>>
>>
>>
>>  Michael Ross <mailto:[hidden email]>
>>> April 28, 2014 12:58 PM
>>> I have an old simple ICE push mower, that might be worth converting.
>>>
>>> ...
>>> What about the shock of the blade hitting something nearly immobile?
That

>>> is a lot of shock that small engines are able to handle - special
>>> consideration in the regard with electric motors?
>>>
>>>  -------------- next part --------------
>> An HTML attachment was scrubbed...
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>> attachments/20140428/339eb705/attachment.htm>
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>> attachments/20140428/339eb705/attachment.jpg>
>> _______________________________________________
>> UNSUBSCRIBE: http://www.evdl.org/help/index.html#usub
>> http://lists.evdl.org/listinfo.cgi/ev-evdl.org
>> For EV drag racing discussion, please use NEDRA
(http://groups.yahoo.com/
>> group/NEDRA)
>>
>>
>>
> _______________________________________________
> UNSUBSCRIBE: http://www.evdl.org/help/index.html#usub
> http://lists.evdl.org/listinfo.cgi/ev-evdl.org
> For EV drag racing discussion, please use NEDRA
(http://groups.yahoo.com/
> group/NEDRA)
>
>


--
Put this question to yourself: should I use everyone else to attain
happiness, or should I help others gain happiness?
*Dalai Lama *

Tell me what it is you plan to do
With your one wild and precious life?
Mary Oliver, "The summer day."

To invent, you need a good imagination and a pile of junk.
Thomas A.
Edison<http://www.brainyquote.com/quotes/quotes/t/thomasaed125362.html>

A public-opinion poll is no substitute for thought.
*Warren Buffet*

Michael E. Ross
(919) 550-2430 Land
(919) 576-0824 <https://www.google.com/voice/b/0?pli=1#phones> Google
Phone
(919) 631-1451 Cell
(919) 513-0418 Desk

[hidden email]
<[hidden email]>
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Re: Recommendations for push mower motor?

EV professor
In reply to this post by Michael Ross
about the plastic disk shearing off. replace it with a sheet metal disk to
fit the motor shaft then place a disk of leather between the new drive disk
and the blade hub, then when you hit a rock the blade slips and no damage
is done.

*Dennis Lee Miles *

*Director   **E.V.T.I. Inc.*

*E-Mail:*  *[hidden email]* <[hidden email]>

   *Phone #* *(863) 944-9913*

Dade City, Florida 33523

 USA




On Mon, Apr 28, 2014 at 3:45 PM, Michael Ross <[hidden email]>wrote:

> I have another battery from these people that seems just fine (after taking
> it apart to see inside)
>
>
> http://www.aliexpress.com/store/product/24V-40AH-LiFePO4-Battery-Pack-Electric-Bicycle-electric-Scooter-bicycle-E-Bike-Lithium-Ion-Long-life/328001_771068114.html
>
> This one is 24V 40Ah LFP and weighs 9kg.  $500 including shipping BMS and
> charger. 3 to 7 day delivery and the met that. These that 18650 cells with
> welded straps for conducting the juice.
>
> I think I will try to get a used 24V B&D instead of reworking my old bottom
> of the line MTD.
>
> I think my wife would love to have an electric mower.  She hates asking me
> to start them for her.  It would be nice not having all the oil checking
> and filling,   And as the current mower works - the rod knocking and
> smoking.  We have an acre of mostly flat yard - 40Ah would go a long ways
> and the charge time is about 2 hours.
>
>
> On Mon, Apr 28, 2014 at 3:25 PM, Peter Eckhoff <[hidden email]> wrote:
>
> > Hello Mike,
> >
> > I'll second what Cal is saying below.  To get the nut off, you have to
> > place a wrench on the nut and "impact" it until the nut loosens.  I would
> > **not** use a compressed air impactor tool.  I use my fist.  Be careful
> > because everything is free wheeling.  If you leave your knuckles in the
> > path of the blade, your knuckles are going to get whacked.  There is no
> > other place to place another wrench unless you weld a nut to the top of
> the
> > motor shaft.
> >
> > Like Cal, I keep a set of several "small plastic blade insulators" on
> hand
> > which is how they are described in the User's Manual.  The word
> "insulator"
> > may seem like a misnomer but it is to "insulate" the shock of hitting a
> > rock from damaging the armature.
> >
> > I converted a corded B&D to cordless.  It uses 9 - 5 amphr 12 volt LA
> AGMs
> > to power the mower.  It is enough to do a 7K square foot lawn.  What used
> > to take me 1.5 hours to do when corded, now takes about 45 minutes.
> >
> > I use a 1.3 amphr AGM for the tripping a small contactor.  This battery
> > goes down faster than the pack.  I would use about a 2 amphr battery for
> > each hour the contactors are tripped.  That should give you plenty of
> > cushion.
> >
> > I wrote a two part article for the Electric Auto Association's Current
> > Events magazine.  I have the submittals in PDF format. The B&D motors are
> > DC universal motors that operate at 120 volts.  The corded version has a
> > full rectifier bridge on a little heat sink.  It was mainly a rewiring
> job
> > to bypass the rectifier.
> >
> > I think the AGMs are the wrong type of battery for this project.
> Normally,
> > when not cutting the lawn, the motor consumes about 4 amps.  When cutting
> > thick grass, the motor consumes about 8 amps. It can spike to 10 amps in
> > real thick grass or when the mower clogs up in thick grass.
> >
> > I have been contemplating upgrading this mower to Lithium.  A set of 40 -
> > 3.2 volt 10 amphr would be about right for an hour's worth of cutting and
> > still have some reserve.  I saw an ad for Shorai 12Volt 12 Amphr
> batteries
> >  for $117 each and they weigh about 1.7 pounds.  My 5.0 amphr batteries
> > weigh 3.5 pounds each for an added weight (starter + pack support +
> > contactor) of 35 pounds onto a mower that weighs 47 pounds for a total of
> > around 82 pounds.  This is about the weight of an ICE push mower.  Twelve
> > Shorai batteries would be around 20 pounds.  The mower would be lighter
> and
> > so would your wallet of $1400 plus shipping.
> >
> > I have thought about purchasing 4 - 100 amphr CALB batteries and then use
> > a converter to step up the voltage to 120 volts.  At an efficiency of
> 85%,
> > the amphrs to the motor would be about 8.5.  I am not sure if a converter
> > could handle that much amperage.  I was going to do some more homework
> > before asking the experts here. Four CALB batteries would be about 600
> > dollars and a converter would run in the lower several hundreds.  The
> > savings would be substantial but I am not sure if the electronics would
> > handle the load.
> >
> > The other thought would be to run the 4 CALBs into an inverter and leave
> > the rectifier bridge intact.  The inefficiency of the inverter plus the
> > inefficiency of the rectifier bridge would likely sap the pack of a lot
> of
> > useful energy.  I think this would be a nonstarter.
> >
> > I know of someone using a self contained electric mower.  You might want
> > to shoot him an email at theadm *A*T* AOL.  If you are in the RTP area,
> we
> > are both "local".
> >
> > Everyone else I see running an electric mower are running with a cord.
>  If
> > you want me to, I will ask my neighbors their brand and opinions.
> >
> >
> > On 4/28/2014 1:27 PM, Cal Frye wrote:
> >
> >> I'm on my second Black and Decker push mower, corded type. I have a
> >> small lawn, so avoiding running over the cord is not a major problem. I
> >> won't advise on motor or batteries, but I can say B&D has a plastic shim
> >> in the stack of washers holding the blade to the motor shaft. Said shim
> >> has raised edges which grip either side of the blade, and an opposing
> >> pair of edges which grip in turn a keyed, square washer above the blade.
> >> This square washer is driven by the motor, and the blade is driven by
> >> the plastic shim. Hit too hard an obstacle, and the plastic edges shear
> >> off and the blade rotates freely.
> >>
> >> This is effective, but is also a wear point, and I've learned to buy the
> >> shims by the half-dozen. My eyes don't always find the rocks in the yard
> >> before the blade does :-(
> >>
> >> Best regards,
> >> -- Cal Frye, www.calfrye.com
> >> /Be an Internet Sceptic/  Stop. Think. Connect.
> >> www.stopthinkconnect.org - Be at least as safe on the
> >> Internet as you are crossing the street!
> >>
> >> "I sincerely believe that banking establishments are more dangerous than
> >> standing armies." -- Thomas Jefferson, letter to John Taylor.
> >>
> >>
> >>
> >>  Michael Ross <mailto:[hidden email]>
> >>> April 28, 2014 12:58 PM
> >>> I have an old simple ICE push mower, that might be worth converting.
> >>>
> >>> ...
> >>> What about the shock of the blade hitting something nearly immobile?
> That
> >>> is a lot of shock that small engines are able to handle - special
> >>> consideration in the regard with electric motors?
> >>>
> >>>  -------------- next part --------------
> >> An HTML attachment was scrubbed...
> >> URL: <http://lists.evdl.org/private.cgi/ev-evdl.org/
> >> attachments/20140428/339eb705/attachment.htm>
> >> -------------- next part --------------
> >> A non-text attachment was scrubbed...
> >> Name: compose-unknown-contact.jpg
> >> Type: image/jpeg
> >> Size: 770 bytes
> >> Desc: not available
> >> URL: <http://lists.evdl.org/private.cgi/ev-evdl.org/
> >> attachments/20140428/339eb705/attachment.jpg>
> >> _______________________________________________
> >> UNSUBSCRIBE: http://www.evdl.org/help/index.html#usub
> >> http://lists.evdl.org/listinfo.cgi/ev-evdl.org
> >> For EV drag racing discussion, please use NEDRA (
> http://groups.yahoo.com/
> >> group/NEDRA)
> >>
> >>
> >>
> > _______________________________________________
> > UNSUBSCRIBE: http://www.evdl.org/help/index.html#usub
> > http://lists.evdl.org/listinfo.cgi/ev-evdl.org
> > For EV drag racing discussion, please use NEDRA (
> http://groups.yahoo.com/
> > group/NEDRA)
> >
> >
>
>
> --
> Put this question to yourself: should I use everyone else to attain
> happiness, or should I help others gain happiness?
> *Dalai Lama *
>
> Tell me what it is you plan to do
> With your one wild and precious life?
> Mary Oliver, "The summer day."
>
> To invent, you need a good imagination and a pile of junk.
> Thomas A. Edison<
> http://www.brainyquote.com/quotes/quotes/t/thomasaed125362.html>
>
> A public-opinion poll is no substitute for thought.
> *Warren Buffet*
>
> Michael E. Ross
> (919) 550-2430 Land
> (919) 576-0824 <https://www.google.com/voice/b/0?pli=1#phones> Google
> Phone
> (919) 631-1451 Cell
> (919) 513-0418 Desk
>
> [hidden email]
> <[hidden email]>
> -------------- next part --------------
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> http://lists.evdl.org/private.cgi/ev-evdl.org/attachments/20140428/eefac1eb/attachment.htm
> >
> _______________________________________________
> UNSUBSCRIBE: http://www.evdl.org/help/index.html#usub
> http://lists.evdl.org/listinfo.cgi/ev-evdl.org
> For EV drag racing discussion, please use NEDRA (
> http://groups.yahoo.com/group/NEDRA)
>
>
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Re: Recommendations for push mower motor?

nicklogan
In reply to this post by Michael Ross
The batteries in the Homelite battery mower I've been using for four years gave out this spring so I went for the 56V EGO mower at Home Despot this weekend since I had a $100 gift card already (still too pricey but I have too many projects going already and couldn't bring myself to buy an ICE mower). I've only used it once but like it so far - very lightweight since it's almost all plastic. It has a 5 year overall warranty and three years on the battery. Even though I have a fairly small yard I expect the battery will give out about two weeks after the warranty ends. The battery and charger design look like they came out of a Halo video game.
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Re: Recommendations for push mower motor?

Peter Eckhoff
In reply to this post by Michael Ross
Thanks Mike for the recommendation.

My blade on my B&D MM675 measures 17.5" even though the specs say 18"
cutting path.  Most of the lower voltage electrics have a 14" blade.  
The smaller mower means more passes.  Something to think about.

On 4/28/2014 3:45 PM, Michael Ross wrote:

> I have another battery from these people that seems just fine (after taking
> it apart to see inside)
>
> http://www.aliexpress.com/store/product/24V-40AH-LiFePO4-Battery-Pack-Electric-Bicycle-electric-Scooter-bicycle-E-Bike-Lithium-Ion-Long-life/328001_771068114.html
>
> This one is 24V 40Ah LFP and weighs 9kg.  $500 including shipping BMS and
> charger. 3 to 7 day delivery and the met that. These that 18650 cells with
> welded straps for conducting the juice.
>
> I think I will try to get a used 24V B&D instead of reworking my old bottom
> of the line MTD.
>
> I think my wife would love to have an electric mower.  She hates asking me
> to start them for her.  It would be nice not having all the oil checking
> and filling,   And as the current mower works - the rod knocking and
> smoking.  We have an acre of mostly flat yard - 40Ah would go a long ways
> and the charge time is about 2 hours.
>
>
> On Mon, Apr 28, 2014 at 3:25 PM, Peter Eckhoff <[hidden email]> wrote:
>
>> Hello Mike,
>>
>> I'll second what Cal is saying below.  To get the nut off, you have to
>> place a wrench on the nut and "impact" it until the nut loosens.  I would
>> **not** use a compressed air impactor tool.  I use my fist.  Be careful
>> because everything is free wheeling.  If you leave your knuckles in the
>> path of the blade, your knuckles are going to get whacked.  There is no
>> other place to place another wrench unless you weld a nut to the top of the
>> motor shaft.
>>
>> Like Cal, I keep a set of several "small plastic blade insulators" on hand
>> which is how they are described in the User's Manual.  The word "insulator"
>> may seem like a misnomer but it is to "insulate" the shock of hitting a
>> rock from damaging the armature.
>>
>> I converted a corded B&D to cordless.  It uses 9 - 5 amphr 12 volt LA AGMs
>> to power the mower.  It is enough to do a 7K square foot lawn.  What used
>> to take me 1.5 hours to do when corded, now takes about 45 minutes.
>>
>> I use a 1.3 amphr AGM for the tripping a small contactor.  This battery
>> goes down faster than the pack.  I would use about a 2 amphr battery for
>> each hour the contactors are tripped.  That should give you plenty of
>> cushion.
>>
>> I wrote a two part article for the Electric Auto Association's Current
>> Events magazine.  I have the submittals in PDF format. The B&D motors are
>> DC universal motors that operate at 120 volts.  The corded version has a
>> full rectifier bridge on a little heat sink.  It was mainly a rewiring job
>> to bypass the rectifier.
>>
>> I think the AGMs are the wrong type of battery for this project. Normally,
>> when not cutting the lawn, the motor consumes about 4 amps.  When cutting
>> thick grass, the motor consumes about 8 amps. It can spike to 10 amps in
>> real thick grass or when the mower clogs up in thick grass.
>>
>> I have been contemplating upgrading this mower to Lithium.  A set of 40 -
>> 3.2 volt 10 amphr would be about right for an hour's worth of cutting and
>> still have some reserve.  I saw an ad for Shorai 12Volt 12 Amphr batteries
>>   for $117 each and they weigh about 1.7 pounds.  My 5.0 amphr batteries
>> weigh 3.5 pounds each for an added weight (starter + pack support +
>> contactor) of 35 pounds onto a mower that weighs 47 pounds for a total of
>> around 82 pounds.  This is about the weight of an ICE push mower.  Twelve
>> Shorai batteries would be around 20 pounds.  The mower would be lighter and
>> so would your wallet of $1400 plus shipping.
>>
>> I have thought about purchasing 4 - 100 amphr CALB batteries and then use
>> a converter to step up the voltage to 120 volts.  At an efficiency of 85%,
>> the amphrs to the motor would be about 8.5.  I am not sure if a converter
>> could handle that much amperage.  I was going to do some more homework
>> before asking the experts here. Four CALB batteries would be about 600
>> dollars and a converter would run in the lower several hundreds.  The
>> savings would be substantial but I am not sure if the electronics would
>> handle the load.
>>
>> The other thought would be to run the 4 CALBs into an inverter and leave
>> the rectifier bridge intact.  The inefficiency of the inverter plus the
>> inefficiency of the rectifier bridge would likely sap the pack of a lot of
>> useful energy.  I think this would be a nonstarter.
>>
>> I know of someone using a self contained electric mower.  You might want
>> to shoot him an email at theadm *A*T* AOL.  If you are in the RTP area, we
>> are both "local".
>>
>> Everyone else I see running an electric mower are running with a cord.  If
>> you want me to, I will ask my neighbors their brand and opinions.
>>
>>
>> On 4/28/2014 1:27 PM, Cal Frye wrote:
>>
>>> I'm on my second Black and Decker push mower, corded type. I have a
>>> small lawn, so avoiding running over the cord is not a major problem. I
>>> won't advise on motor or batteries, but I can say B&D has a plastic shim
>>> in the stack of washers holding the blade to the motor shaft. Said shim
>>> has raised edges which grip either side of the blade, and an opposing
>>> pair of edges which grip in turn a keyed, square washer above the blade.
>>> This square washer is driven by the motor, and the blade is driven by
>>> the plastic shim. Hit too hard an obstacle, and the plastic edges shear
>>> off and the blade rotates freely.
>>>
>>> This is effective, but is also a wear point, and I've learned to buy the
>>> shims by the half-dozen. My eyes don't always find the rocks in the yard
>>> before the blade does :-(
>>>
>>> Best regards,
>>> -- Cal Frye, www.calfrye.com
>>> /Be an Internet Sceptic/  Stop. Think. Connect.
>>> www.stopthinkconnect.org - Be at least as safe on the
>>> Internet as you are crossing the street!
>>>
>>> "I sincerely believe that banking establishments are more dangerous than
>>> standing armies." -- Thomas Jefferson, letter to John Taylor.
>>>
>>>
>>>
>>>   Michael Ross <mailto:[hidden email]>
>>>> April 28, 2014 12:58 PM
>>>> I have an old simple ICE push mower, that might be worth converting.
>>>>
>>>> ...
>>>> What about the shock of the blade hitting something nearly immobile? That
>>>> is a lot of shock that small engines are able to handle - special
>>>> consideration in the regard with electric motors?
>>>>
>>>>   -------------- next part --------------
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>>> group/NEDRA)
>>>
>>>
>>>
>> _______________________________________________
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>> For EV drag racing discussion, please use NEDRA (http://groups.yahoo.com/
>> group/NEDRA)
>>
>>
>

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Re: Recommendations for push mower motor?

Peter Eckhoff
In reply to this post by nicklogan
 >>http://www.aliexpress.com/store/product/24V-40AH-LiFePO4-Battery-Pack-Electric-Bicycle-electric-Scooter-bicycle-E-Bike-Lithium-Ion-Long-life/328001_771068114.html <<
Thanks Mike for the recommendation.

My blade on my B&D MM675 measures 17.5" even though the specs say 18"
cutting path.  Most of the lower voltage electrics have a 14" blade.  
The smaller mower means more passes.  Something to think about.
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Re: Recommendations for push mower motor?

Michael Ross
In reply to this post by Peter Eckhoff
Hi thank you all for the advice, and so fast.

I took the advice to work with a cordless mower rather than re-purpose an
ICE mower.   Craigslist brought me a B&D CMM1200 which seems to be quite a
hoss at 1200W.   24V.   Bagger/mulcher,  1.5A charger.  The only thing I
could see amiss was a missing knob on the push structure replaced with a
hex nut, and a worn out blade.  The batteries look like two gel Pb cells
shrink wrapper together - not very big by the scale of the diagram.  The
wheel leveling seemed very easy - hope it holds up.  I like the thick
plastic hull - I think that makes a lot of sense - polyethylene can take a
lot of abuse and will bend not break. The owner did not have a very big
yard so he couldn't say much about mowing time.  $145 seemed like a very
fair price.

I will be curious to see where it cuts off and to what voltage it charges.

I guess I will have to find some other thing to convert.


On Mon, Apr 28, 2014 at 6:05 PM, Peter Eckhoff <[hidden email]> wrote:

> Thanks Mike for the recommendation.
>
> My blade on my B&D MM675 measures 17.5" even though the specs say 18"
> cutting path.  Most of the lower voltage electrics have a 14" blade.  The
> smaller mower means more passes.  Something to think about.
>
>
> On 4/28/2014 3:45 PM, Michael Ross wrote:
>
>> I have another battery from these people that seems just fine (after
>> taking
>> it apart to see inside)
>>
>> http://www.aliexpress.com/store/product/24V-40AH-
>> LiFePO4-Battery-Pack-Electric-Bicycle-electric-Scooter-
>> bicycle-E-Bike-Lithium-Ion-Long-life/328001_771068114.html
>>
>> This one is 24V 40Ah LFP and weighs 9kg.  $500 including shipping BMS and
>> charger. 3 to 7 day delivery and the met that. These that 18650 cells with
>> welded straps for conducting the juice.
>>
>> I think I will try to get a used 24V B&D instead of reworking my old
>> bottom
>> of the line MTD.
>>
>> I think my wife would love to have an electric mower.  She hates asking me
>> to start them for her.  It would be nice not having all the oil checking
>> and filling,   And as the current mower works - the rod knocking and
>> smoking.  We have an acre of mostly flat yard - 40Ah would go a long ways
>> and the charge time is about 2 hours.
>>
>>
>> On Mon, Apr 28, 2014 at 3:25 PM, Peter Eckhoff <[hidden email]>
>> wrote:
>>
>>  Hello Mike,
>>>
>>> I'll second what Cal is saying below.  To get the nut off, you have to
>>> place a wrench on the nut and "impact" it until the nut loosens.  I would
>>> **not** use a compressed air impactor tool.  I use my fist.  Be careful
>>> because everything is free wheeling.  If you leave your knuckles in the
>>> path of the blade, your knuckles are going to get whacked.  There is no
>>> other place to place another wrench unless you weld a nut to the top of
>>> the
>>> motor shaft.
>>>
>>> Like Cal, I keep a set of several "small plastic blade insulators" on
>>> hand
>>> which is how they are described in the User's Manual.  The word
>>> "insulator"
>>> may seem like a misnomer but it is to "insulate" the shock of hitting a
>>> rock from damaging the armature.
>>>
>>> I converted a corded B&D to cordless.  It uses 9 - 5 amphr 12 volt LA
>>> AGMs
>>> to power the mower.  It is enough to do a 7K square foot lawn.  What used
>>> to take me 1.5 hours to do when corded, now takes about 45 minutes.
>>>
>>> I use a 1.3 amphr AGM for the tripping a small contactor.  This battery
>>> goes down faster than the pack.  I would use about a 2 amphr battery for
>>> each hour the contactors are tripped.  That should give you plenty of
>>> cushion.
>>>
>>> I wrote a two part article for the Electric Auto Association's Current
>>> Events magazine.  I have the submittals in PDF format. The B&D motors are
>>> DC universal motors that operate at 120 volts.  The corded version has a
>>> full rectifier bridge on a little heat sink.  It was mainly a rewiring
>>> job
>>> to bypass the rectifier.
>>>
>>> I think the AGMs are the wrong type of battery for this project.
>>> Normally,
>>> when not cutting the lawn, the motor consumes about 4 amps.  When cutting
>>> thick grass, the motor consumes about 8 amps. It can spike to 10 amps in
>>> real thick grass or when the mower clogs up in thick grass.
>>>
>>> I have been contemplating upgrading this mower to Lithium.  A set of 40 -
>>> 3.2 volt 10 amphr would be about right for an hour's worth of cutting and
>>> still have some reserve.  I saw an ad for Shorai 12Volt 12 Amphr
>>> batteries
>>>   for $117 each and they weigh about 1.7 pounds.  My 5.0 amphr batteries
>>> weigh 3.5 pounds each for an added weight (starter + pack support +
>>> contactor) of 35 pounds onto a mower that weighs 47 pounds for a total of
>>> around 82 pounds.  This is about the weight of an ICE push mower.  Twelve
>>> Shorai batteries would be around 20 pounds.  The mower would be lighter
>>> and
>>> so would your wallet of $1400 plus shipping.
>>>
>>> I have thought about purchasing 4 - 100 amphr CALB batteries and then use
>>> a converter to step up the voltage to 120 volts.  At an efficiency of
>>> 85%,
>>> the amphrs to the motor would be about 8.5.  I am not sure if a converter
>>> could handle that much amperage.  I was going to do some more homework
>>> before asking the experts here. Four CALB batteries would be about 600
>>> dollars and a converter would run in the lower several hundreds.  The
>>> savings would be substantial but I am not sure if the electronics would
>>> handle the load.
>>>
>>> The other thought would be to run the 4 CALBs into an inverter and leave
>>> the rectifier bridge intact.  The inefficiency of the inverter plus the
>>> inefficiency of the rectifier bridge would likely sap the pack of a lot
>>> of
>>> useful energy.  I think this would be a nonstarter.
>>>
>>> I know of someone using a self contained electric mower.  You might want
>>> to shoot him an email at theadm *A*T* AOL.  If you are in the RTP area,
>>> we
>>> are both "local".
>>>
>>> Everyone else I see running an electric mower are running with a cord.
>>>  If
>>> you want me to, I will ask my neighbors their brand and opinions.
>>>
>>>
>>> On 4/28/2014 1:27 PM, Cal Frye wrote:
>>>
>>>  I'm on my second Black and Decker push mower, corded type. I have a
>>>> small lawn, so avoiding running over the cord is not a major problem. I
>>>> won't advise on motor or batteries, but I can say B&D has a plastic shim
>>>> in the stack of washers holding the blade to the motor shaft. Said shim
>>>> has raised edges which grip either side of the blade, and an opposing
>>>> pair of edges which grip in turn a keyed, square washer above the blade.
>>>> This square washer is driven by the motor, and the blade is driven by
>>>> the plastic shim. Hit too hard an obstacle, and the plastic edges shear
>>>> off and the blade rotates freely.
>>>>
>>>> This is effective, but is also a wear point, and I've learned to buy the
>>>> shims by the half-dozen. My eyes don't always find the rocks in the yard
>>>> before the blade does :-(
>>>>
>>>> Best regards,
>>>> -- Cal Frye, www.calfrye.com
>>>> /Be an Internet Sceptic/  Stop. Think. Connect.
>>>> www.stopthinkconnect.org - Be at least as safe on the
>>>> Internet as you are crossing the street!
>>>>
>>>> "I sincerely believe that banking establishments are more dangerous than
>>>> standing armies." -- Thomas Jefferson, letter to John Taylor.
>>>>
>>>>
>>>>
>>>>   Michael Ross <mailto:[hidden email]>
>>>>
>>>>> April 28, 2014 12:58 PM
>>>>> I have an old simple ICE push mower, that might be worth converting.
>>>>>
>>>>> ...
>>>>> What about the shock of the blade hitting something nearly immobile?
>>>>> That
>>>>> is a lot of shock that small engines are able to handle - special
>>>>> consideration in the regard with electric motors?
>>>>>
>>>>>   -------------- next part --------------
>>>>>
>>>> An HTML attachment was scrubbed...
>>>> URL: <http://lists.evdl.org/private.cgi/ev-evdl.org/
>>>> attachments/20140428/339eb705/attachment.htm>
>>>> -------------- next part --------------
>>>> A non-text attachment was scrubbed...
>>>> Name: compose-unknown-contact.jpg
>>>> Type: image/jpeg
>>>> Size: 770 bytes
>>>> Desc: not available
>>>> URL: <http://lists.evdl.org/private.cgi/ev-evdl.org/
>>>> attachments/20140428/339eb705/attachment.jpg>
>>>> _______________________________________________
>>>> UNSUBSCRIBE: http://www.evdl.org/help/index.html#usub
>>>> http://lists.evdl.org/listinfo.cgi/ev-evdl.org
>>>> For EV drag racing discussion, please use NEDRA (
>>>> http://groups.yahoo.com/
>>>> group/NEDRA)
>>>>
>>>>
>>>>
>>>>  _______________________________________________
>>> UNSUBSCRIBE: http://www.evdl.org/help/index.html#usub
>>> http://lists.evdl.org/listinfo.cgi/ev-evdl.org
>>> For EV drag racing discussion, please use NEDRA (
>>> http://groups.yahoo.com/
>>> group/NEDRA)
>>>
>>>
>>>
>>
> _______________________________________________
> UNSUBSCRIBE: http://www.evdl.org/help/index.html#usub
> http://lists.evdl.org/listinfo.cgi/ev-evdl.org
> For EV drag racing discussion, please use NEDRA (http://groups.yahoo.com/
> group/NEDRA)
>
>


--
Put this question to yourself: should I use everyone else to attain
happiness, or should I help others gain happiness?
*Dalai Lama *

Tell me what it is you plan to do
With your one wild and precious life?
Mary Oliver, "The summer day."

To invent, you need a good imagination and a pile of junk.
Thomas A. Edison<http://www.brainyquote.com/quotes/quotes/t/thomasaed125362.html>

A public-opinion poll is no substitute for thought.
*Warren Buffet*

Michael E. Ross
(919) 550-2430 Land
(919) 576-0824 <https://www.google.com/voice/b/0?pli=1#phones> Google Phone
(919) 631-1451 Cell
(919) 513-0418 Desk

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Re: Recommendations for push mower motor?

David Nelson-5
In reply to this post by Michael Ross
I picked up a B&D 24V push mower for free. It needed batteries and a
charger. I removed the charging circuit & batteries and replaced the
batteries with two sets of GBS 20Ah
(http://www.kta-ev.com/Battery_4_GBS_3_2V_20AH_cells_p/bat-gbs-lfmp20ahx4.htm)
which are an almost exact size replacement for the lead acid
batteries. I installed a self powered digital volt meter in place of
the old analog meter and carefully bottom balanced the pack. I know
when to stop mowing when the voltage reads 20V when not cutting grass.
They bounce back to just over 3V per cell. I don't have a charging
plug yet so I still have to remove the cover and charge the batteries
with my bench power supply. Charging to 3.4V per cell average means I
don't have to worry about overcharging the cells. Yes, I checked. It
seems like it just runs for ever. It could mulch mow the yard of a
1200 ft^2 ranch style house on a 6000 ft^2 lot (I'm not sure of the
lawn area) and still have energy left.

On Mon, Apr 28, 2014 at 9:58 AM, Michael Ross <[hidden email]> wrote:

> I have an old simple ICE push mower, that might be worth converting.
>
> Can anyone recommend the sort of motor I should look for?
>
> Re-purposing a motor would be nice.
>
> I would use LFP batteries.
>
> What about the shock of the blade hitting something nearly immobile? That
> is a lot of shock that small engines are able to handle - special
> consideration in the regard with electric motors?
>
> Mounting the blade seem non-trivial?  Hints?
>
> Thanks!
>
> I just saw a Li ion powered mower on line for $500.  supposed to run for 45
> minutes and charge back in 30.  That sounds like a practical target.  48V
> pack.  Weighs 62lb.
>
> Any thought on this side of the equation?  36V?  60V?  Capacity needed to
> go 45 minutes?
>
> --
> Don't believe everything you read on the Internet - Abraham Lincoln
>
> A public-opinion poll is no substitute for thought.
> *Warren Buffet*
>
> Michael E. Ross
> (919) 550-2430 Land
> (919) 576-0824 <https://www.google.com/voice/b/0?pli=1#phones> Google Phone
> (919) 631-1451 Cell
> (919) 513-0418 Desk
>
> [hidden email]
> <[hidden email]>
> -------------- next part --------------
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>



--
David D. Nelson
http://evalbum.com/1328
http://www.levforum.com
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Re: Recommendations for push mower motor?

Michael Ross
Thanks, David, that sounds like a good fit.  Sounds like the 40AH I was
looking at are way overkill.

They ship in 2 to 3 weeks - sounds like they are not stocking, just
brokering for a Chinese manufacturer.

This is all speculation, because I may like the Pb cells in it just fine.
 I wonder how much they would  cost.  I am not familiar with buying lead
batteries, except from the auto parts store.



On Mon, Apr 28, 2014 at 10:00 PM, David Nelson <[hidden email]> wrote:

> I picked up a B&D 24V push mower for free. It needed batteries and a
> charger. I removed the charging circuit & batteries and replaced the
> batteries with two sets of GBS 20Ah
> (
> http://www.kta-ev.com/Battery_4_GBS_3_2V_20AH_cells_p/bat-gbs-lfmp20ahx4.htm
> )
> which are an almost exact size replacement for the lead acid
> batteries. I installed a self powered digital volt meter in place of
> the old analog meter and carefully bottom balanced the pack. I know
> when to stop mowing when the voltage reads 20V when not cutting grass.
> They bounce back to just over 3V per cell. I don't have a charging
> plug yet so I still have to remove the cover and charge the batteries
> with my bench power supply. Charging to 3.4V per cell average means I
> don't have to worry about overcharging the cells. Yes, I checked. It
> seems like it just runs for ever. It could mulch mow the yard of a
> 1200 ft^2 ranch style house on a 6000 ft^2 lot (I'm not sure of the
> lawn area) and still have energy left.
>
> On Mon, Apr 28, 2014 at 9:58 AM, Michael Ross <[hidden email]>
> wrote:
> > I have an old simple ICE push mower, that might be worth converting.
> >
> > Can anyone recommend the sort of motor I should look for?
> >
> > Re-purposing a motor would be nice.
> >
> > I would use LFP batteries.
> >
> > What about the shock of the blade hitting something nearly immobile? That
> > is a lot of shock that small engines are able to handle - special
> > consideration in the regard with electric motors?
> >
> > Mounting the blade seem non-trivial?  Hints?
> >
> > Thanks!
> >
> > I just saw a Li ion powered mower on line for $500.  supposed to run for
> 45
> > minutes and charge back in 30.  That sounds like a practical target.  48V
> > pack.  Weighs 62lb.
> >
> > Any thought on this side of the equation?  36V?  60V?  Capacity needed to
> > go 45 minutes?
> >
> > --
> > Don't believe everything you read on the Internet - Abraham Lincoln
> >
> > A public-opinion poll is no substitute for thought.
> > *Warren Buffet*
> >
> > Michael E. Ross
> > (919) 550-2430 Land
> > (919) 576-0824 <https://www.google.com/voice/b/0?pli=1#phones> Google
> Phone
> > (919) 631-1451 Cell
> > (919) 513-0418 Desk
> >
> > [hidden email]
> > <[hidden email]>
> > -------------- next part --------------
> > An HTML attachment was scrubbed...
> > URL: <
> http://lists.evdl.org/private.cgi/ev-evdl.org/attachments/20140428/7e307136/attachment.htm
> >
> > _______________________________________________
> > UNSUBSCRIBE: http://www.evdl.org/help/index.html#usub
> > http://lists.evdl.org/listinfo.cgi/ev-evdl.org
> > For EV drag racing discussion, please use NEDRA (
> http://groups.yahoo.com/group/NEDRA)
> >
>
>
>
> --
> David D. Nelson
> http://evalbum.com/1328
> http://www.levforum.com
> _______________________________________________
> UNSUBSCRIBE: http://www.evdl.org/help/index.html#usub
> http://lists.evdl.org/listinfo.cgi/ev-evdl.org
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> http://groups.yahoo.com/group/NEDRA)
>
>


--
Put this question to yourself: should I use everyone else to attain
happiness, or should I help others gain happiness?
*Dalai Lama *

Tell me what it is you plan to do
With your one wild and precious life?
Mary Oliver, "The summer day."

To invent, you need a good imagination and a pile of junk.
Thomas A. Edison<http://www.brainyquote.com/quotes/quotes/t/thomasaed125362.html>

A public-opinion poll is no substitute for thought.
*Warren Buffet*

Michael E. Ross
(919) 550-2430 Land
(919) 576-0824 <https://www.google.com/voice/b/0?pli=1#phones> Google Phone
(919) 631-1451 Cell
(919) 513-0418 Desk

[hidden email]
<[hidden email]>
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Re: Recommendations for push mower motor?

David Nelson-5
KTA drop ships them from another supplier in the US. I've always had
good luck with KTA so that is why I ordered from them. It sounded like
they periodically get orders in and ship from that. I don't remember
how long it took mine to show up but it was less than 3 weeks. They
are a really nice size. Basically they are like small versions of the
TS cells I put in my Gizmo. The lids on the packs I received actually
covered the exposed terminals better than the ones in the picture on
KTAs website. If you capacity test to the specs that the manufacturer
gives they deliver 20Ah but if you limit your charge to a more
reasonable high of 3.6V at 1A or 3.4V at nearly 0A for your cutoff and
stop discharge at 2.5V with a 0.5C load you will realize close to
19Ah. I'm not at home right now so I can't check my data.

On Mon, Apr 28, 2014 at 8:13 PM, Michael Ross <[hidden email]> wrote:

> Thanks, David, that sounds like a good fit.  Sounds like the 40AH I was
> looking at are way overkill.
>
> They ship in 2 to 3 weeks - sounds like they are not stocking, just
> brokering for a Chinese manufacturer.
>
> This is all speculation, because I may like the Pb cells in it just fine.
>  I wonder how much they would  cost.  I am not familiar with buying lead
> batteries, except from the auto parts store.
>
>
>
> On Mon, Apr 28, 2014 at 10:00 PM, David Nelson <[hidden email]> wrote:
>
>> I picked up a B&D 24V push mower for free. It needed batteries and a
>> charger. I removed the charging circuit & batteries and replaced the
>> batteries with two sets of GBS 20Ah
>> (
>> http://www.kta-ev.com/Battery_4_GBS_3_2V_20AH_cells_p/bat-gbs-lfmp20ahx4.htm
>> )
>> which are an almost exact size replacement for the lead acid
>> batteries. I installed a self powered digital volt meter in place of
>> the old analog meter and carefully bottom balanced the pack. I know
>> when to stop mowing when the voltage reads 20V when not cutting grass.
>> They bounce back to just over 3V per cell. I don't have a charging
>> plug yet so I still have to remove the cover and charge the batteries
>> with my bench power supply. Charging to 3.4V per cell average means I
>> don't have to worry about overcharging the cells. Yes, I checked. It
>> seems like it just runs for ever. It could mulch mow the yard of a
>> 1200 ft^2 ranch style house on a 6000 ft^2 lot (I'm not sure of the
>> lawn area) and still have energy left.
>>
>> On Mon, Apr 28, 2014 at 9:58 AM, Michael Ross <[hidden email]>
>> wrote:
>> > I have an old simple ICE push mower, that might be worth converting.
>> >
>> > Can anyone recommend the sort of motor I should look for?
>> >
>> > Re-purposing a motor would be nice.
>> >
>> > I would use LFP batteries.
>> >
>> > What about the shock of the blade hitting something nearly immobile? That
>> > is a lot of shock that small engines are able to handle - special
>> > consideration in the regard with electric motors?
>> >
>> > Mounting the blade seem non-trivial?  Hints?
>> >
>> > Thanks!
>> >
>> > I just saw a Li ion powered mower on line for $500.  supposed to run for
>> 45
>> > minutes and charge back in 30.  That sounds like a practical target.  48V
>> > pack.  Weighs 62lb.
>> >
>> > Any thought on this side of the equation?  36V?  60V?  Capacity needed to
>> > go 45 minutes?
>> >
>> > --
>> > Don't believe everything you read on the Internet - Abraham Lincoln
>> >
>> > A public-opinion poll is no substitute for thought.
>> > *Warren Buffet*
>> >
>> > Michael E. Ross
>> > (919) 550-2430 Land
>> > (919) 576-0824 <https://www.google.com/voice/b/0?pli=1#phones> Google
>> Phone
>> > (919) 631-1451 Cell
>> > (919) 513-0418 Desk
>> >
>> > [hidden email]
>> > <[hidden email]>
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>> > For EV drag racing discussion, please use NEDRA (
>> http://groups.yahoo.com/group/NEDRA)
>> >
>>
>>
>>
>> --
>> David D. Nelson
>> http://evalbum.com/1328
>> http://www.levforum.com
>> _______________________________________________
>> UNSUBSCRIBE: http://www.evdl.org/help/index.html#usub
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>> For EV drag racing discussion, please use NEDRA (
>> http://groups.yahoo.com/group/NEDRA)
>>
>>
>
>
> --
> Put this question to yourself: should I use everyone else to attain
> happiness, or should I help others gain happiness?
> *Dalai Lama *
>
> Tell me what it is you plan to do
> With your one wild and precious life?
> Mary Oliver, "The summer day."
>
> To invent, you need a good imagination and a pile of junk.
> Thomas A. Edison<http://www.brainyquote.com/quotes/quotes/t/thomasaed125362.html>
>
> A public-opinion poll is no substitute for thought.
> *Warren Buffet*
>
> Michael E. Ross
> (919) 550-2430 Land
> (919) 576-0824 <https://www.google.com/voice/b/0?pli=1#phones> Google Phone
> (919) 631-1451 Cell
> (919) 513-0418 Desk
>
> [hidden email]
> <[hidden email]>
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>



--
David D. Nelson
http://evalbum.com/1328
http://www.levforum.com
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Re: Recommendations for push mower motor?

EVDL Administrator
In reply to this post by Michael Ross
On 28 Apr 2014 at 19:17, Michael Ross wrote:

> Craigslist brought me a B&D CMM1200 which seems to be quite a hoss at
> 1200W.   24V.   Bagger/mulcher,  1.5A charger.

Good find!  Note that 1200 watts is >peak< - ask those little gel batteries
to deliver 50 amps for more than a few seconds and see how far they get you!

Unless B&D have made some drastic charger improvements in recent years
(which I doubt), you can significantly improve your battery life with these
mowers by chucking out the crappy wall wart charger they come with, and
replacing it with a good smart charger.

David Roden - Akron, Ohio, USA
EVDL Administrator

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Re: Recommendations for push mower motor?

Lee Hart
>> Craigslist brought me a B&D CMM1200 which seems to be quite a hoss at
>> 1200W. 24V. Bagger/mulcher, 1.5A charger.

EVDL Administrator wrote:
> Good find!  Note that 1200 watts is>peak< - ask those little gel batteries
> to deliver 50 amps for more than a few seconds and see how far they get you!
>
> Unless B&D have made some drastic charger improvements in recent years
> (which I doubt), you can significantly improve your battery life with these
> mowers by chucking out the crappy wall wart charger they come with, and
> replacing it with a good smart charger.

I agree. I have a 36v Black and Decker mower, bought from a damaged
freight outlet (the self-propelled feature is broken, and one wheel was
bent).

The charger I got with it is first-class grade-A (for awful) junk. The
best they could get for a dollar. Don't use it unless you only want your
batteries to last a year or or two.

Mine came with AGMs, not gels. But they are really cheap off-brand ones.

--
If we knew what we were doing, it wouldn't be called research, would it?
        -- Albert Einstein
--
Lee Hart's EV projects are at http://www.sunrise-ev.com/LeesEVs.htm
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Re: Recommendations for push mower motor?

Martin WINLOW
In reply to this post by Michael Ross
What sort of RPM does a mower use?  The corded electric Mountfield we use does not appear to have a gearbox.  So, would a 36/48V cordless circular saw be a possible starting point (if there is such a beast!)?  It'd certainly make battery swapping very easy! MW


On 28 Apr 2014, at 17:58, Michael Ross wrote:

> I have an old simple ICE push mower, that might be worth converting.
>
> Can anyone recommend the sort of motor I should look for?
>
> Re-purposing a motor would be nice.
>
> I would use LFP batteries.
>
> What about the shock of the blade hitting something nearly immobile? That
> is a lot of shock that small engines are able to handle - special
> consideration in the regard with electric motors?
>
> Mounting the blade seem non-trivial?  Hints?
>
> Thanks!
>
> I just saw a Li ion powered mower on line for $500.  supposed to run for 45
> minutes and charge back in 30.  That sounds like a practical target.  48V
> pack.  Weighs 62lb.
>
> Any thought on this side of the equation?  36V?  60V?  Capacity needed to
> go 45 minutes?
>
> --
> Don't believe everything you read on the Internet - Abraham Lincoln
>
> A public-opinion poll is no substitute for thought.
> *Warren Buffet*
>
> Michael E. Ross
> (919) 550-2430 Land
> (919) 576-0824 <https://www.google.com/voice/b/0?pli=1#phones> Google Phone
> (919) 631-1451 Cell
> (919) 513-0418 Desk
>
> [hidden email]
> <[hidden email]>
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Re: Recommendations for push mower motor?

Michael Ross
In reply to this post by Lee Hart
I have an Amrel programmable power supply 4A, 60V.  Very handy for Li-ion.

I am a lead acid dunce.  Can I imitate a smart charger with the Amrel
 power supply?

Are there different protocols for conventional, AGM and Gel?  I assume so.


On Tue, Apr 29, 2014 at 9:40 AM, Lee Hart <[hidden email]> wrote:

> Craigslist brought me a B&D CMM1200 which seems to be quite a hoss at
>>> 1200W. 24V. Bagger/mulcher, 1.5A charger.
>>>
>>
> EVDL Administrator wrote:
>
>> Good find!  Note that 1200 watts is>peak< - ask those little gel batteries
>> to deliver 50 amps for more than a few seconds and see how far they get
>> you!
>>
>> Unless B&D have made some drastic charger improvements in recent years
>> (which I doubt), you can significantly improve your battery life with
>> these
>> mowers by chucking out the crappy wall wart charger they come with, and
>> replacing it with a good smart charger.
>>
>
> I agree. I have a 36v Black and Decker mower, bought from a damaged
> freight outlet (the self-propelled feature is broken, and one wheel was
> bent).
>
> The charger I got with it is first-class grade-A (for awful) junk. The
> best they could get for a dollar. Don't use it unless you only want your
> batteries to last a year or or two.
>
> Mine came with AGMs, not gels. But they are really cheap off-brand ones.
>
>
> --
> If we knew what we were doing, it wouldn't be called research, would it?
>         -- Albert Einstein
> --
> Lee Hart's EV projects are at http://www.sunrise-ev.com/LeesEVs.htm
> _______________________________________________
> UNSUBSCRIBE: http://www.evdl.org/help/index.html#usub
> http://lists.evdl.org/listinfo.cgi/ev-evdl.org
> For EV drag racing discussion, please use NEDRA (http://groups.yahoo.com/
> group/NEDRA)
>
>


--
Put this question to yourself: should I use everyone else to attain
happiness, or should I help others gain happiness?
*Dalai Lama *

Tell me what it is you plan to do
With your one wild and precious life?
Mary Oliver, "The summer day."

To invent, you need a good imagination and a pile of junk.
Thomas A. Edison<http://www.brainyquote.com/quotes/quotes/t/thomasaed125362.html>

A public-opinion poll is no substitute for thought.
*Warren Buffet*

Michael E. Ross
(919) 550-2430 Land
(919) 576-0824 <https://www.google.com/voice/b/0?pli=1#phones> Google Phone
(919) 631-1451 Cell
(919) 513-0418 Desk

[hidden email]
<[hidden email]>
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