Propeller opinions and advice

Personally I use APCs, but I NEVER hand crank them. This brand is pretty well in balance as received. For others, you can scrap off some of the surface of the back side of the heavy blade using a curved X-Acto blade before using your 200 grit paper. Our club instructors recommend Master Airscrews for trainers -- they take more of a beating :-)

I'm not a prop snob. APC's are excellent meat slicers. I'm not friendly toward them when the meat in question is mine. But I do have to admit that they are a superior propeller for most applications.

Master Airscrew is tough and durable. No doubt. These days, I try to avoid the kind of flying that favors these props, if you know what I mean. Still, I have several around all of the time and will probably buy more in the future.

Wood props are my favorite. I guess it is that "organic thing". Sometimes I actually enjoy balancing them. I balance mine using Krylon clear. Anyone else do this?

Ed Cregger

instead.Wooden

------------------------------------------------- Hello Ed, Zinger wooden props rarely need balancing. APC composite props rarely need much balancing. Master Airscrew props are terrible. Sometimes you even have to sand on the hub, or tap a screw with washers into the hub of these props. They are also very inefficient.

I use both Zinger and APC props exclusively now.

I have propeller related equations on my one of my web pages.

I prefer wood props just for their sheer beauty, and they usually balance very nicely. They are also lighter, and your engine will likely pick up a couple of RPMs. I don't like the APC props, because they are hideously ugly. For me, life is all about beauty, so I wouldn't want an ugly prop anymore than an ugly woman.

The glass filled black Screw Master props are the worst abomination on the face of the earth. They come in a terrible state of balance, and I always have to file a huge flat spot on the hub and hack some material off the end or the face. You can often get away with not balancing the APC and wood props but never the dreaded SMs! Without being balanced, they'll shake your airframe apart!

SM's only virtue is they stand up better to incidences at the flying field than the other two (maybe?), but I truly hate using them. Lately, after breaking several of them just hitting some weeds at the end or side of the runways, I'm thinking the wood props might not be any worse.

Ciao,

Mr Akimoto

Me either,...but at least I can afford the props and they don't get fat and complain a lot after I bring them home.

Hi Ed --

When we supplied a bunch of props for Q-500 racing (Rev-Up) we balanced by dabbing a bit of epoxy on with a Q-tip. Instant balance as no evaporation :-)

Cheers -- Lyman

I'll have to keep that one in mind, Lyman. That is a great technique.

Ed Cregger

I balance my props with red electrical tape. I change the size and location of the tape as required to balance. I usually end up with a piece about one inch long and 1/2 inch wide somewhere a little more than halfway out on the prop from the hub. I attach the tape with equal lengths on each side of the prop and the fold on the leading edge. Never had a piece come off yet. The tape also lets me know at a glance that the prop has been balanced.

I prefer APC props. The Master Airscrew props are inefficient and woefully out of balance. To balance a prop, first throw away that 200 sandpaper! Get some COARSE, 60 or 100 grit. Sand the BACK SIDE of the heavy blade out toward the tip but don't sand the tip itself. It doesn't take long at all.

Use the back side of an Xacto #11 blade like a scraper and take off the flashing on the edge of the prop (the side your hand will contact while cranking). You want to get rid of the sharp edge. Otherwise, you'll slice your hands up if trying to hand crank.

I have used the clear spray method. It works fine. Just be sure to let it dry before testing the balance each time! Otherwise you're also weighing the solvent that's going to evaporate out of it!

YGBSM!

Master Airscrew seems to have performed K&B's trick.

Back when the K&B engines first came out, they were sweet. Turning one over by hand was a pleasure. Then, as time went on, they became rough and inconsistent.

Master Airscrew black props of the seventies were not like the last ones I bought a year or two ago. The new ones actually had the center hole off center. You can't balance a prop like that. It went into the trashcan. It wasn't just one of their props. It was everyone of their props that I had bought in the same order. I scratched them off the buy list. I'll just keep running the survivors I have from the seventies. They are completely different animules. I really hate to bad mouth any manufacturer, since I know that things can happen once and never again. But all the folks that I have talked to that have bought them since then are having the same experience. Please prove me wrong, Master Airscrew.

I don't fly models to have them be the most efficient these days. Just flying is enough. In that vein, the Master Airscrew props have their place, if they are true.

Ed Cregger

Very true, Jim.

Ed Cregger