Will a 3 bladed prop work on 2 strokes. I would like to try one on my 75 ST but dont know what size to get?

Thanks
tks1

It will work, take the recommended two blade size and reduce either the pitch or the diameter by one inch.

Thanks. Simple enough.

Thanks again
tks1

tks1:

The blue and white plane has Magnum XL 46 engines, Zinger 10x8 props. The little dark blue twin has Cox props on the AMD 0.061 engines. The big single has a Graupner 12x8 on a K&B 61.

They all fly well with their 3-blade props.

Bill.

Thanks William. I just saw your post. You have a 12X8 on your 61. Im thinking to start with a 13X6 on my ST75 or should I start at 13X8? I dont want high speed - just scale flight and climb (Beaver). I am running a 14X6 2 bladed now - it also only needs about 1/3 to 1/2 throttle to fly

Trent

Trent:

Rule of thumb: Pitch determines speed, diameter determines engine load.

If your Beaver's speed is where you want it with the 6" pitch, and I think that would be about right, the 13" diameter will fly it fine.

This is supposing you don't have any tendency to over rev with the 14x6 two blade. You might find the plane/engine combo is perfectly happy with a 14x6 three blade.

But I would start with the 13x6.

Bill.