rainedave

My Feedback: (1)

Having returned to r/c last fall, I haven't bought an APC 5.7x3 in fifteen years (I still have a decent stash from FF days).

I just got some from Tower and my question is: What happened?! When did they change them?!!! I love the old ones. Are the new ones just as good, or, maybe even better? They don't appear to be as well made to me. Why would they go and "fix" something that wasn't broken!

New on top; old on bottom:

Andrew

$$$$$$$$$$$$$$$$$ maybe???

burtcs

rainedave:

Like yourself I aquired a stash of the old 5.7-3 props. They always seemed to run like crazy on KK Tee Dees. I don't know anything about the NEW 5.7-3. I've pretty much stopped trying to run Tee Dees in FF competion and run and run Russian. Stehls, AMEs and VAs.

These engines seem to like the APC 5.5-2 and 6-2s, the result is I can't comment on the new 5.7-3 but as you
noted they DID change them.

The old prop was a simitar the new one has srtaight blades. The 6-2 is worth a try, everthing seems to run well with them OK cubs, Tee Dees and of course the Russians. If your sport flying, I haven't a clue.

HTH - Steve B.

rainedave

My Feedback: (1)

Thank you, Steve. I threw in a couple of the 6x2s in my order so I'll soon see how they do. Here's one on my AME .061.

In 1/2A Nostalgia a Black Widow with the old 5.7x3 was a great setup. That was before people were using Medallions (yeah, right). I have a George Perryman Raunchy in the garage that I flew with a BW at one point. Absolutely the flattest gliding FF plane I've ever flown. Polyhedral swept-back stab. Perryman was so original.

burtcs

rainedave

Cause your a nice guy here's the tip. Build your own product engine up out of parts. I had been flying a 1/2 Ram Rod with
one I cobbeled up out of parts for a number of years. It would turn up to 19,500 by my tach (6-2 prop) Nice model. Last summer I finally broke the crank (sob). But I had another I could use, this one would do 20,500.

An associate told me the engine did quit sound peaked, so I peaked it a little better. It got up around one hundred feet when it tore the wings off. Dont need anything in 1/2A NOS but RV parts and some 60% nitro.

The end - Steve B.

rainedave

My Feedback: (1)

Steve, that's pretty much what I used to do. I would assemble various reedy parts and find the combination that gave the best performance. But, then, I was never that hard core about the engine performance race of FF. I found that a well built model of a good design would do well whether the engine was turning 16,000 or 19,000. Altitude is of little use if the model loses it in the transition or simply glides poorly. I've caught thermals and almost lost models with the props on backwards for trimming.

The Ramrod is a classic I have plans for but never built. BTW, the Raunchy plans are available from AMA. It has a super thin airfoil and climbs like a rocket.

ptulmer

My Feedback: (5)

The older one looks like it is much heavier. The new one is one of my favorite props for all-around performance. I'd bet if you ran them back-to-back, you'd find the newer style is better. Especially in terms of thrust.

rainedave

My Feedback: (1)

Thanks, pt. I have the old one on the Sure Shark right now. Next time out I'll fly it once and then put a new one on and see if I can tell any difference in the air. It may very well unload a bit more.

ptulmer

My Feedback: (5)

... or it could be mostly cosmetic... Could we tell a 1% difference? Maybe. Tell you what, send the Sure Shark down here with some props and fuel and I'll test that theory for you. I'd hate to see you waste valuable building time.[&:]

rainedave

My Feedback: (1)

Sure thing, Sharkey![8D]