Which propeller?

[bc_rcgroup]

G'day all,

I am building a Sig Spacewalker 2 (1/4 scale, 84" span) with a McCulloch 32cc gas engine (ex weedwacker). I am intending to use it to tow gliders amongst other things. What size prop should I buy to start with?

Thanks,

Ben

[pettit]

If you have the ground clearance, try an APC 18-6 wide blade.

That'll be a good place to start.

It's all about experimentation. The "best" prop is the one that you feel works best. Other people's experiences can only serve as a starting point.

Dick Pettit
Associate Editor
R/C REPORT Magazine

[bc_rcgroup]

Dick, thanks for the advice. How much clearance should I allow between the prop and ground? It looks like I have about 10 inches from engine centreline to ground with the model held level.

Cheers,

Ben Coleman

[pettit]

If you do the math, with an 18" prop and 10" of clearance, that's only 1" of space between the spinning prop tip and the ground, if there's no grass.

Also not bouncing like on a rough landing.

I'll go out right now and buy some stock in "Zinger" or APC"...

Dick Pettit
Associate Editor
R/C REPORT Magazine

[bc_rcgroup]

Righto, I'll go and find myself the equivalent 3-blader, from what I've read that would be a 17x7.

Cheers,

Ben

[Enriki]

Install a taller tire, maybe a 1" block under gear, or the best bet is TNT for taller gear that would look good on your bird.