Dumas 17" Tiger Moth - Prop and Rubber?

[Steve85]

I've just about finished a Dumas 17" Tiger Moth (their kit #208), and need some advice on an appropriate prop and rubber combo. The kit comes with a red 5" Guillow's(!) prop and enough 1/8" tan rubber for a single loop. Is this the best combo? I have 4.75", 6" and 7" Peck Polymers props, along with 5" and 6" red Guillow's ones, and 1/16", 3/32" and 1/8" tan rubber, so I've got lots of possibilities.

I'm hoping to test fly her at the club in a gym on Monday, so any advice would be very helpful. Thanks in advance.

Steve

[Dave K]

The 6" peck prop two loops of 3/32" would be a good place to start. possibly less rubber if it is build light.

[Megowcoupe]

If the airplane is anywhere around 20-24 grams or so, then I'll bet a nice loop of 1/8" about 2x noseblock to motor peg wouldn't be a bad start.

A lot of prop selection depends on weight and bipes are often tough. I must admit, I'd probably start with a 6" Peck prop and might try bending in a little extra pitch. Odds are the airplane will be easier to trim with a 5" prop though. The biggest problem with the Guillow props is that they are heavy, and their blade shape isn't great (neither is the Peck prop though). The guillow's props are the only plastic props I know of with true helical pitch though, but that doesn't seem to outweigh their disadvantages, I've never had good luck with them. The best blade shape I know of is on the black 6" Tern prop- which would probably be too much prop for the airplane come to think of it, so maybe a 5" is a better starting point.

Sam