Electric lawnmower project...

[John Hill]

I started with one of these...

..........and thought it might be easier to use if it had an electric motor.

First project, sharpen the blade..

http://flic.kr/p/apKsUp
...dont bother with the sound as the router motor on the grinder is a real screamer!  

Pedants will see that the grindstone is rotating in the wrong direction,  too bad, the router motor does not like to be reversed.

[Stilldrillin]

John.
That takes me back to the 70's........ 

I used to be every gardener's friend, each springtime. Night shifts, with my Churchill cylindrical grinder! 

David D

[Pete49]

waiting for another JH installment ....going by the bike mod last time this will be a doozy
Pete

[John Hill]

I mounted the 1/6 HP motor and got things like chain adjustment sorted but as feared the motor is way too small.

I am not sure about electric motor ratings, this one is much bigger than the 1/3HP motor on my generic asian drill press which is placarded at 350watts while the 1/6 HP motor is placarded at 2 amp (i.e. 500watts).

There is only one stage of reduction, chain drive direct to the reel at about 650RPM, which would be good for cutting grass and throwing it into the catcher but this motor is just not up to it so today, if all goes well, I will add a belt stage to reduce the speed and load on the motor.

[cfellows]

Don't know how this compares to a mower with a rotary blade, but the commercial electric mower I used to have had a motor rated at 12 amps.  I loved the mower, small and light, but I hated the cord!  Now I have a Lawnboy gas mower.  It's bigger and a lot heavier so it wears me out mowing around all shrubs, trees, and planters.  

I've thought it would be neat to have an electric mower and make a battery and 120 volt inverter back pack.  Seems like that would be cheaper and lighter than the heavy, ridiculously priced cordless mowers.  I could also use the back pack to power my electric weed whacked!

Chuck

[AdeV]

I don't know what the current draw of a typical lawnmower is, but 12A @ 110v RMS = 1320W; your inverter won't be a problem (an APC UPS would be ideal, in fact), but the batteries are going to weigh a ton! I have a 3000W UPS here (and it's capable of delivering that, for about 10 mins, from fully charged), and I can barely lift the thing. I'd certainly hate to have to carry it around while mowing the lawn; and if it takes more than 10 mins to do your lawn?


On the other hand, battery lawnmowers have existed for years, I'm sure if you took the old lead acid battery off & replaced it with modern LiPo batteries, you'd get better range & power for less weight.

But surely, the mad-modderist of all, would be to get a quadrocopter, fit blades underneath each propeller, and then fly it over your lawn at the correct height?