I always hold my APC propellers with a piece of cloth when loosening or tightening my prop nuts on my OS46FX and OS61FX. The prop edges are real sharp even after sanding ! I was wondering if it will be easier and more convenient if I were to lock my piston with a "piston stopper" (need to remove glow plug) and then proceed to loosen/tighten the nut without the need to hold the propeller. My concern is will the top of the piston get damaged by the stopper or the piston is sufficiently hard and strong to withstand the pressure. Tha last thing I want is a deformed piston !! Where can I buy a good piston stopper for my two engines? Thanks for the inputs ..........

I would rename it the "Connecting Rod Bender".You would most likely damage you engine the first time you tried that. Don't do it.

JJ

Are you truly serious?

You are going to screw something in the plug hole and jam the piston against it just to change the prop?

Who dreams up this stuff?

Ed S

If it's really a problem, go to your hardware store and buy a piece of rubber hose big enough to go over one prop blade for a handle, or even a piece of pvc pipe.

Just a thought, JJ

Rajul,

I use a piston stopper on my Jets and Heli engines. I think the torque required to bolt on a prop is too high though. Get a cheap leather gardening glove to hold your prop while tightening and you won't need to worry about sharp edges.

Ed,

This tool is sold for the Heli, Jet & car engines.

Mark M.

Thanks Mallory, Miller. I think you're right. So, what is the real purpose of these "piston stoppers" ? When do you need to use 'em ? Thx again...................

It would be better to just use a glove to hold the prop. I wouldn't feel safe putting that much stress on the rod.

When I raced r/c cars I used to fill the cylinder will after run oil and then put the plug back in to lock the engine. The only time I did that was when the flywheel had come loose and the nut was still tight (loctite).

Gubbs, do you mean to say you used a piston stopper to tighten your flywheel ?.................

Dynamite sells a piston stop tool, Ive been using it for years on my .12 and .21 size engines to tighten my clutch. obviuosly u cant just apply a ton of torque or u will damage something. But for my airplanes i just use a towel to protect my hand.