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Your 1/8 HP motors will probably take somewhere between 100W and 150W, depending on efficiency.
If you use a car alternator, it will be 3 phase and you'll need another motor to spin it, so it's really not worthwhile to go that route.
Some AC motors don't care if they're fed AC or DC (like a mains driven power drill), so you could check if it will run on DC.
However... Hawing a switcher to make the voltage needed will also make it potentially lethal, so I'd advice against it (and so will your laws on electricity if they're anything like in DK, where anything above 48V is considered high voltage).
Personally, I'd use the motors for something mains driven (automatic door, bed adjuster, TV lift etc.) and get some other motors for mobile apps. Any car junk yard have plenty of motors for pocket change - lots of different sizes to find as well: Wiper motors, automatic antenna motors, power window motors, power seat motors, fan motors and they're all 12V if you keep away from trucks.
[...] could I provide half the voltage and twice the amperage? I'm SURE it matters how I get that power, but is there any leeway? That'd be the same power...
I know, I was planning on keeping the lawnmower mostly gas driven, and run a belt off of the motor that powers the blade. (I'd test this without the blade on of course ) I haven't really thought this part out, but I was debating cannibalizing a FWD lawnmower that doesn't work in our hilly, muddy yard very well and just seeing how the drive mechanism was connected.
So you're saying for me (a definitely not certified electrician) mess with "high voltage" is illegal? I did not know that.
I've always though of this route. Windshield wiper motors are usually pretty easy to get to, the rest, not so much. I've just never taken the time to go to a junk yard and pull them out.
Sounds like something you have to be careful about, but if you're up to it (mechanically speaking), the gas engine could be used alone, with electromagnetic clutches to engage/disengage the drive to each side separately.
I originally though (something like) that, but the lawnmower... drive isn't powerful enough to push itself up the hill. (I live on a pretty steep hill, if my yard was flat it'd be easy )
Or, the mechanism powering the drive slips (cause I doubt it'd be a direct drive, as that'd probably be dangerous). I bet it's just a belt and it slips when it faces too much resistance. Also I can stop the wheels without the motor stopping. So, if I tighten up the belt (if it is one), it'd have a bit more torque. Or even maybe make it a chain drive? How dangerous would that be?
The clutches would be the interesting part. First off, after a quick google they're not the cheapest things in the world...
Well, would I REALLY need 2 clutches if I still kept the original belt in place? If the "on-off" mechanism still worked for the drive, I could just turn it off to stop, turn it on to start one wheel, and use one clutch to stop the other wheel to turn... but then I could only turn one way... That'd be a crazy lawnmower to watch! Swiveling around like a mad machine.And now I'm just rambling.
It's probably a (centrifugal?) clutch, but I'm not that much into lawnmowers (I rate mowing about as exciting as watching paint dry ). If it takes off when you speed up the motor, it probably is.Perhaps you can find a workshop manual for it and see if you can tighten things up, without loosing the ability to stop with the motor running.
You could make it run a spiral track of course, but if your lawn is square...Seriously, you should be able to make do with only one side turning, if you plan the track it will follow and remember... 270° left equals 90° right.
I don't think it's a centrifugal clutch. The motor stays at the same RPM all the time. I honestly think it's a pulley moving back and forth when you pull the handle. I'll check it out.
See I really wanted to be able to make it do a couple different tracks. Since I have a bunch of mud in my yard if I always go the same way I get big ruts in it. Then the wheels get stuck in the ruts and lower the blade which hits the raised mud between the ruts and goes dull and stall.
Sure I could make it a spiral track, but it'd be a lot easier to program if it could turn both ways.
This is my lovely picture of my yard.
I usually cut it side to side just cause it's annoying walking up and down the hill (and I've been known to slip and let the lawnmower go and since the thing to shut it off by itself gets stuck it just kinda keeps going till I run it down)
Hi,Nah, if it's handle controlled it isn't. Centrifugal clutches engage when you rev up and v.v.
I wonder if you know Flymo and their range of hovering Mowers? In case you don't, they'll never dig in, as they... Hover over the grass and you can push (or pull) them with one finger for that reason - after my old man bought one of those, me and my siblings almost fought for the right to mow (quite different from our pre-Flymo days).If I ever take on the task of making an autonomous mower, this will be my preferred base - and then I'd probably drive it like a swamp raft (with a huge fan).
[...] But wouldn't the wind blow the grass out of the way?