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/cue sniggers from the Peanut Gallery

We have a Cox ride-on lawnmower that has been sitting in our yard for a number of years, slowly decomposing. It's been sitting for so long that I can't actually remember why it was parked in the first place, but recent problems with our John Deere ride-on (intermittent starting, which is a real bugger when you've loaded it onto a trailer and driven 20 minutes down to road to cut your vacant block) have spurred me into action! I suppose it was one of those 'gunnadoo' projects of my step-fathers, but they almost never get finished.

A cursory lookover shows it is a belt-driven mower, single cut, nfi about the transmission, probably hydrostatic or something (forward and reverse with the one pedal). Step-father wants the motor to put into yet another ride-on, which is currently occupying valuable real estate in the garage. So he can keep it.

Current plan (although open to suggestions) is a two-motor setup: one driving the blades, and one for propulsion. The property it is to be used on is 'flat' but with a east-west tilt, with about a 1.5M drop from boundry to boundry (~20M). No hills or gullies, and about 1000M². DC Sepex motors seem to be the go (although major has suggested a 'cumulative compound'), as they'll try to maintain speed. Batteries were going to be deep-cycle PBa, but if I'm only going to get 300 or so cycles out of them I might as well go Lithium straight up.

I'm not going to be mowing hay with this thing, so I was hoping to keep the blade motor to ~2kW. I was hoping to direct-drive the blades, but I read in other threads that it might not be such a great idea, as there's no 'slip' if I hit something. Speed isn't a big issue, so the driving motor could be maybe half a kW? A 48 volt system is the target.

Can anyone who's converted their own mower give me any advice or suggestions before I go ahead and start spending money/pulling things apart?

Cheers.
 

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I'm not going to be mowing hay with this thing, so I was hoping to keep the blade motor to ~2kW. I was hoping to direct-drive the blades, but I read in other threads that it might not be such a great idea, as there's no 'slip' if I hit something. Speed isn't a big issue, so the driving motor could be maybe half a kW? A 48 volt system is the target.

Can anyone who's converted their own mower give me any advice or suggestions before I go ahead and start spending money/pulling things apart?
Hi Belli,

Motor size estimates are likely in the ball park. I have similar size lawn tractor at 48V. I don't mow with it. The current for moderate speed, like you'd do for mowing is around 10 amps.

For the blade motor, that is a tough one to estimate. I think maybe you should go larger. 2kW continuous rated might hack it, but the blade can really load down with a patch of tall wet grass. Like when it stalls a 12 hp gas engine ;) And this type of overload is why I suggested a compound motor. A SepEx would work well if you have a controller on it. But if you want to use the blade motor without a controller, you should use the compound motor, like you often find on forklifts for the pumps.

Mowers and small tractors are great "getting started" EV projects. There have been a few on this board. I think there should be a sub-forum for such EVs, like "Tractors, Mowers, Non-Road Worthy and Weird Stuff". Hey Woodsmith, how about it :)

major
 

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Mowers and small tractors are great "getting started" EV projects. There have been a few on this board. I think there should be a sub-forum for such EVs, like "Tractors, Mowers, Non-Road Worthy and Weird Stuff". Hey Woodsmith, how about it :)

major
A 'Wierd Stuff' forum might get some of us blocked at work!;)

It may be worth considering but there may need to be some definitions of 'Non Road Worthy' and 'Wierd'.:D
 

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A 'Wierd Stuff' forum might get some of us blocked at work!;)

It may be worth considering but there may need to be some definitions of 'Non Road Worthy' and 'Wierd'.:D
I was hoping that the forum administrators would fashion a suitable title :p

Might be a good place for your tractor thread :) I do hope you guys consider this. Go karts is another class. We have a separate one for bikes. Seems like there should be a better place for non-cars. Once they mixed into the "conversions and builds" they become really hard to relocate.
 

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I was hoping that the forum administrators would fashion a suitable title :p

Might be a good place for your tractor thread :) I do hope you guys consider this. Go karts is another class. We have a separate one for bikes. Seems like there should be a better place for non-cars. Once they mixed into the "conversions and builds" they become really hard to relocate.
I do enough weird stuff to qualify. I'm all for the forum.

Maybe Titled NON LICENSED Electric Conversions and Vehicle projects.

Jim
 

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Discussion Starter #7
For the blade motor, that is a tough one to estimate. I think maybe you should go larger. 2kW continuous rated might hack it, but the blade can really load down with a patch of tall wet grass. Like when it stalls a 12 hp gas engine ;)
If I can store the mower in the shipping container on-site, I can be sure to mow it before it gets to that stage (unless we get a solid month of rain, like now. It's like I'm scything wheat). At the moment, I have to make sure I have a car with a towbar available, an empty trailer (I had to unload a Kenworth bullbar from the trailer on Monday so I could use it), a working mower, and a free morning. :)

A SepEx would work well if you have a controller on it. But if you want to use the blade motor without a controller, you should use the compound motor, like you often find on forklifts for the pumps.
Yes, a SepEx w/controller looks to be about $500-$600 pp. Unfortunately, forklift suppliers in this neck of the woods are robber-barons, and I don't see used forklifts come up too often. Do you have any suggestions for new Compound motors?
 

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Do you have any suggestions for new Compound motors?
Where to get motors :confused: And new ones at that ;) And you likely don't want to pay much :) This is a problem.

You can buy PM, Series, and some SepEx motors from EV parts companies, some of which advertise on this board. I don't think I ever saw one which offered compound motors. You can search the web and likely will come up short.

I actually use a compound 6.6 inch motor on my eTractor. It is about 30 yrs old. Originally from a floor cleaning machine. I got it from a university lab which was discarding it because it didn't work. I fixed it (just wires) and it has been running my tractor for like 15 yrs. Rusty and looks like crap, but then so does the rest of the eTractor. I really need to buy a couple cans of paint :eek:

Point is.....I don't know :confused: Maybe start by visiting some motor rebuild shops in your area. Forklift repair or dealers. Give them a call first and take a box of donuts. Get resourceful :)

Good luck,

major
 

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Where to get motors :confused: And new ones at that ;) And you likely don't want to pay much :) This is a problem.
Well, I don't want to pay too much. :)

Maybe start by visiting some motor rebuild shops in your area. Forklift repair or dealers. Give them a call first and take a box of donuts. Get resourceful :)
Frankly, I don't think there are any in this area. Maybe on the southside of the city, or maybe the nearest SimsMetal scrapyard gets them in occasionally. Can't hurt to ask, I suppose.
 

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Hi Bellistner
Frankly, I don't think there are any in this area. Maybe on the southside of the city, or maybe the nearest SimsMetal scrapyard gets them in occasionally. Can't hurt to ask, I suppose.

There are two in Invercargill (pop 40,000) so I bet there are quite a few in Queensland,
definitely worth looking

You may have to drop in on somebody with a forklift and ask where he gets it serviced - all of the big DIY stores will have forklifts - M10,. Bunnings, ...
 

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Kool :cool: I think that would do the job very well :) You could get adjustment on blade speed. Even the pros don't have that :p
Might be the go then. At the very least it'll get me started.

Hi Bellistner
There are two in Invercargill (pop 40,000) so I bet there are quite a few in Queensland,
definitely worth looking
I'll definately be looking. Once I get a workbench I expect I'll be well and truly stocking it (and putting perfboard on all the walls so I can actually find things :eek: ). :)
 
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