since i'm converting my first weedy, i'm not sure how to make some of the parts(on the lathe)
my question is, how is the drive spacer(metal part that goes on the shaft between the fly wheel and the prop)stay locked to the shaft? do i use a set screw and grind a flat spot on the shaft? how do the store bought conversions work?
im getting close to finishing my plane and i need to make these parts to get it running

also does the prop washer(between the prop on the nut) have those groves like the drive spacer or is it flat on both sides??

Typically, the washer on the front of the prop is flat on both sides.

As for the hub behind the prop, I've seen them flat on the magneto side and grooved on the prop side to keep it from slipping.

Just make your prop hub so that it will fit flush against the magneto and it will stay put when you tighten the prop nut down.

The magneto is usually on a keyed and tapered shaft----it's not going anywhere. All the prop hub is for; is basically a long spacer. Once you line the magneto up on the keyway and put the prop hub on-- then the prop and tighten it all up-- it should stay put.

You could drill a couple of holes through the prop hub. Drill from the top down-- straight into the magneto. Drill into the magneto. Just drill two holes into the hub/magneto and tap them for set screws. Then you can run your set screws into the magneto. That would keep the hub from slipping-- if your really worried about it.

I would probably avoid filing a flat spot on the crank. Might weaken it or throw the balance off.

I'm no machinist- but thats how most of my conversion parts look. I've ordered all my parts from other machinists.

The metal device you refer is the prop hub and even the professional workshops who convert these engines usually do not put in a locking pin or screw because it is not needed.

The running direction of the engine keeps it tightened except in case of backfire where possibility of the whole front end flying away exists.

The only problems I've seen on a converted engine was..........and this guy was a machinist...
He didn't allow enough length on the prop adapter and had to put two or three washers behind the prop nut...and he also didn't tighten the coil down the coil enough...ala coming loose and breaking the mount in flight....other than that..."aint nothin to it."

well im buying a prop this week end, so ill be able to figure out how long the parts need to be.

my muffler is coming together but i think its a bit on the heavy side....it will most likly be around 5 oz, is that heavy for a muffler?

I've always used the stock steel one...Noise regs. at our field...18x6 prop will do it justice..

BB1

well the stock stealer comes in at 11.5 oz and i figure that with me useing all steel for the conversion parts(except for the prop hub) it should come in at around the same as if i went out and dun payed all that green for somethin i can woop up(sorry i just had too use that acsent)

p.s. i have no clue on how what fuel lines are to go to the carb. right now there are 2 lines, one on the top on on the bottom of the carb, which one is the inlet? is one a over flow?

If the motor is inverted it's the bottom tube that goes to the gas tank...the other is a return line and can be soldered up or pluged..