AJsToyz

Whats a good propeller to run in general?

I have a few TF Power points and they seem to lack quality. The holes on every one are either not centered or no true. You can balance one length wise but width , there is about an extra 1/8" of wood on every one. I have a 10-7 on one plane that actually tracks like a heli head , looks like two props on this thing. I was raised on wood , but I'm open for Ideas.

Andy

DarZeelon

Andy,


While I can personally testify only for the Bolly Clubman, those GFN props offered by Master Airscrew, Graupner and several other manufacturers are pretty good.

Bollys have a perfect balance (I don't know about others) and I don't remember ever having to do any more than scraping off the casting slag.

But several APC props, considered by most to be the best aerodynamic design, were reported in some threads here to have imperfect balance and even to have the hole drilled askew.


Wood props? The old Rev-Up props were near perfect.

AJsToyz

Thank you very much for the information!

I just bought a wood Master Airscrew that needs just a small small small balance. My main concern is the center hole. I have two APC props a guy gave me that the centers are not true. I also have some power points and old TF M series props that none of the holes are centered. I'm still trying prop sizes < do to small wheels and tall grass> once I find a set up I like , I'll need a few props, I thonk I'll gives these a go.

Thanks again. Andy

DarZeelon

Andy,


Even if the hole in the wood prop is visibly off-center, don't worry about it.

As long as the prop balances out on a finger-tip balancer, it is usable.


Please read [link=http://www.rcuniverse.com/forum/m_4936657/anchors_4936657/mpage_1/key_balancing/anchor/tm.htm#4936657]this thread[/link] (and some others) to understand why paying any more for a balancer is a waste of money.

AJsToyz

The problem is that the side to side is so far off you cannot balance it. You would need to hog off at least 1/8" just to get started. You can get a good end to end balance but you will never get a true balance.

DarZeelon

Andy,


I know Bolly wood props are balanced after the machining and varnishing processes are completed.

The balancer finds the exact C/G of the ready prop and drills the hole there.
It happens that due to density differences in the wood, the hole may come out a bit off-center in the hub.

It is not that it will be 1/4" from one side and 3/4" from the other... If that happens I am sure the prop will be scrapped.
But if you measure with a pair of vernier calipers, the hole may be up to 1 mm closer to one side than to the other, and/or one blade may be up to 1 mm longer than the other.

Such differences cannot be seen in flight quality, but I am sure blade tracking must be true.

Since the prop is spun by the engine around its C/G, it will stay that way.

AJsToyz

Dar,

Thanks for the input , I'm testing prop sizes in the morning then I thinl I'm going to try Bolly.

Andy

DarZeelon

Andy,


Currently Bolly wood props are available from sizes 15x7 and upward. No smaller sizes.
Normal sizes +.5" are available in GFN Bolly Clubman series.

The Clubmans are, after only scraping off the casting slag, in very good balance as well.

Currently only sizes up to 13.5x8 are available, but very soon sizes up to 16.5x8 and 3-D props will also be offered.