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Engine basics => Engine set up tips => Topic started by: Randy Powell on April 26, 2007, 03:50:01 PM
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OK, so I finally got some flights on the Novi at the Portland contest last weekend. Still needs some trimming (and, of course, I forgot the tool at home - now modified to not need a special tool). But I had some observations and some questions. I flew it initially with a Thunder Tiger Cyclon 11.5 x 4.5 prop and it seems to do well on the plane. But I have to set the engine a bit rich to get a consisent run that isn't too fast. Great for the dead calm weather we had most of the weekend, but in wind, I'd be a bit concerned. I also tried a Bolly 11.25 x 4 two blade that also worked well, but in order to get decent lap times, I had to dial the engine up a bit. Seemed happy there, but didn't have the authority I really liked with the Cyclone above 45 degrees. I think something like an 11.25 or 11.5 x 4.25 two blade Bolly may be the ticket.
Any thoughts?
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Hi Randy on my P/A 40 U L I use 11 1/4 x 4.5 3 bld Bill Lee prop with Pipe at about 10 K RPM
the other P/A 40 UL with Header muffler, I use a 11x4.2 Bolie 3bld, I get 5.1 - 5.3 laps with 65 ft lines.
Good luck the P/A 40 UL's are sweet. My new Imitation Plus II will have eather 40 or 46 VF
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OK, so I finally got some flights on the Novi at the Portland contest last weekend. Still needs some trimming (and, of course, I forgot the tool at home - now modified to not need a special tool). But I had some observations and some questions. I flew it initially with a Thunder Tiger Cyclon 11.5 x 4.5 prop and it seems to do well on the plane. But I have to set the engine a bit rich to get a consisent run that isn't too fast. Great for the dead calm weather we had most of the weekend, but in wind, I'd be a bit concerned. I also tried a Bolly 11.25 x 4 two blade that also worked well, but in order to get decent lap times, I had to dial the engine up a bit. Seemed happy there, but didn't have the authority I really liked with the Cyclone above 45 degrees. I think something like an 11.25 or 11.5 x 4.25 two blade Bolly may be the ticket.
Any thoughts?
Hi Randy
I have setup the engine with those props and many more, The Cyclone is typically too much pitch, the 4 pitch Bollys are too little, Best I have had was the 12x 4 pitched to 4.5, the 11 1\4 x 4 pitched to 4.25, and the 11 x 4 n # blade is killer pitched at 4 1\4 to just a little above that. The wide blade Majik 10.5 x 4.5 work well in smaller planes.
I do not recomend trying to repitch the plastic propsas none I have ever repitched will stay!, they ALWAYS come back within 1 day
I also flew my plane at KOI with a wood 11 \2 x 4 1\4 BYO. This is using Sig Champion 5% with 1 ounce of Aero-1
The motor make very good power with 5% nitro with almost zero windup, 10% here will accelerate a little
Regards
Randy
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Thanks Randy,
I have a Zinger 12 x 5 that's been cut down to 11.5 x 4.25 and reshaped that I want to try. Been hanging around Pat Johnston too long, I guess. Plane to try that this weekend along with a Bolly 11.5 x 4.25 (this from a 12 x 4).
We'll see how it comes out. As I said, in dead calm, the Cyclone worked pretty well, but the engine was loafing. In wind it would be, ah, interesting. Really want to fine something else where the engine is running a bit faster and working less.
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Thanks Randy,
I have a Zinger 12 x 5 that's been cut down to 11.5 x 4.25 and reshaped that I want to try. Been hanging around Pat Johnston too long, I guess. Plane to try that this weekend along with a Bolly 11.5 x 4.25 (this from a 12 x 4).
We'll see how it comes out. As I said, in dead calm, the Cyclone worked pretty well, but the engine was loafing. In wind it would be, ah, interesting. Really want to fine something else where the engine is running a bit faster and working less.
HI Randy
The repitched 11.5 x 4.25 should work very well for you. I also think you will find the engine is not at all prone to any runaway problems, it is a very mild low timed motor that has a very wide envelop that it will run in
Regards
Randy
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It's certain that the engine is a horse. Even loafing along it's has more than enough power to pull my 48oz classic plane around.
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It's certain that the engine is a horse. Even loafing along it's has more than enough power to pull my 48oz classic plane around.
Hi Randy
The PA ultralight will pull a 65 ounce impact better than a OS VF 40 that weighs over 3 ounces more, and using the same or a bigger prop.
The little motor is the most tailorable motor up or down on power I have ever seen. It is flying many planes from 500 to 700 sq inches and from 35 to 65 ounces in weight.
Let me know how your prop trials go ;D
Regards
Randy
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Randy,
Well, some more flights. THE prop at the moment, or at least the one that seems the happiest, is an 11 x 4N Bolly 3 blade that is pitched to about 4.4. I liked the power steering feel I'm getting above 45 degrees. The Cyclone still seems the best all around prop, but in the wind (and it was windy when I was flying), the 3 blade Bolly is the best. Might be a bit fast in dead calm. I'm going to try pitching one to about 4.2 or so and try that when the wind calms down. The tracking also seems better with the 3 blade. The 11.5 x 4.25 2 blade (from cut down 12 x 4 Bolly) also worked pretty well, but was a bit slow. Maybe a 1/10 or so more pitch might do the trick there.
I hope to have a good all around prop, one for the wind and one for the calm worked out before the Northwest Regionals next weekend. I'm close.
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Randy, I have been watching this thread and was wondering what you ended up with?
Cheers.....
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Rob,
For calm conditions, the Thundertiger Cyclone 11.5 x 4.5 was the best all around prop. For the wind, a Bolly 11 x 4.25N three blade seemed to work best. I also liked a Bolly 11.25 x 4.5 two blade. Probably as good as the Cyclone. But I was glad I was using the $3 Cyclone when I bounce the plane off the pavement last weekend. The plane is repairable, but the prop is toast.