Some other approaches: user BruceM set up an air tank which runs a Gast air motor which turns a rubber wheel which spins up the flywheel. He used a foot pedal to engage/disengage the rubber wheel. Eric at rockymountainpowersource.com has a prototype for an electric motor which turns a rubber wheel which spins up the flywheel. It auto-disengages, I believe somehow with centripetal force. Mike Montieth at listeroids.com was cutting ring gears and mounting them onto flywheel for use with automotive starters, but his supplier now does this for him. A few electric motors, such as those on the genuine start-o-matics, double as starters.
The air motor/smog pump ideas are interesting and I'm sure would work, except then I have to build an air tank, and it's a limited start option - once you're out of air, you're back to the hand crank. Regardless, I'm sure that would work well most of the time, but I'm looking for something to reduce the number of parts on this setup, and an air start would increase the number of parts and failure points. This project is getting wildly out of control already, and an air tank/compressor/control system would probably cause my head to explode.
The electric motor with a rubber wheel would be pretty good, now that I think about it. I could still use a belt-driven alternator on that flywheel, and the rubber wheel could run up against the flywheel in the "lee" area where the belt wouldn't be touching. Still more complex than a starter generator, but not unrealistic. Any part numbers for the engines used on those? Not sure what would need to happen to automatically push the roller up against the flywheel and back it off again...
Interesting about Mike Montieth's electric start rumors. I obtained a pulley from him for the aircraft starter/generator (and a few other things) but his work schedule has led him to be very slow in replies and deliveries. His work quality is excellent but without information on what it is he's selling, it's a difficult situation to figure out what I could possibly implement that he's built. If he has ring gears, there is no evidence that he's selling them on his website, and in fact he makes it seem that he's stopped production of them except with finished engines (
http://www.listeroids.com/Electric_start_update.html) and there are no pictures or clues of anything else - it's mostly just rumors. I'd be happy with a ring gear if I could get one to fit on my 12/2 Powersolutions/JKson, but I've never seen someone selling or making them, and the prospect of having one cut that large is a bit on the "extreme" side from a cost perspective. Plus, the few car-starter ring setups I've actually seen or seen pictures of, the starter is on the "outside" of the flywheel, and my chassis is narrower than that, so a belt-driven setup is the way to go if I want to keep things physically compact and centered between the ends of the crank, I think.
Another issue: The amperage on the starter/generator needs to be more than 15A or even 22A at 12V, which is another problem with the ones I see on eBay even if they are powerful enough. I probably need around 60 amps with all the stuff that I'm running at peak - relays, gauges, fuel heaters, fuel rack hold electromagnets etc. and other systems that aren't directly related to the engine, so I probably would be happier having some headroom at 100 or 120 amps. Granted, my normal load will probably be around 20A, but that's still quite a bit. I hate the prospect of converting from 110 or 220 into 12V when I already have a 12V supply with a belt attached to it, so tapping off my main A/C generator is something I'd like to avoid at all costs (and it just seems like a bad idea to have the main load and the control circuits hooked to the same power supply - it's years of large-scale networking that tells me that "out-of-band control" and "primary load" networks, systems, and power supplies should never cross-pollute, and this is a similar concept.)
Stan - very nice Arrow starter - good find! Looks like it costs as much as my car! :-) Still requires "by hand" activation, and I'm looking for something a bit more cheap, automated, and integrated with an alternator...
Doug - the starter and that whole 10/1 is nice, but how does one get a ring gear to install behind a 12/2 flywheel? Or "where does one get" is the better question...
At this point, I still see two options as being most clear:
1) get a starter/generator motor with the right pulley, amperage, torque, and rotation (best solution!)
2) put both an electric starter AND a generator on the flywheel in some combination of:
- an automotive starter and ring gear on the flywheel
- a rubber wheel friction starter
- a belt-driven alternator
- an automotive starter driving a small ring gear on the alternator pulley (hmm...)
To do #1, I need to find the "magic" starter/generator for probably a small plane engine.
To do #2, I need to think some more. :-)
JT
