which props are recommended
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which props are recommended
Hello everybody , there are many of you on the aero sites so someone should be able to give me some ideas, i hope .
I have two engines the 1st one a magnum .21 and the 2nd is an os .25 , i wish to run them with Graupner triple blades but i dont know which sizes can be used, and i dont want to damage them either, i also have a .15 coming from a friend not sure what make it is or what triples that can take ? i hope someone out there can help.
Thanx in advance, Rick
I have two engines the 1st one a magnum .21 and the 2nd is an os .25 , i wish to run them with Graupner triple blades but i dont know which sizes can be used, and i dont want to damage them either, i also have a .15 coming from a friend not sure what make it is or what triples that can take ? i hope someone out there can help.
Thanx in advance, Rick
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RE: which props are recommended
I have little experience with engines under .46. I do have a plane with 3 blade and they recommended a size smaller than recommended for 2 blade. I have a 4 stroke OS 91 and have a 3 blade 12X6 prop on it which was recommeded for that engine., Check the paper work that came with the engine and then use that as a rule of thumb as to what 3 blade would work.
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RE: which props are recommended
thanx for the tips , i dont want to get supersonic speeds out of the engines, as they will be fitted to ...? not sure wat you call it but the designed aeroplane/flying machine?? will be fixed to a a wire and spinning in circles, but i want them with 3 blade props , i am unsure what 2 blade props they use too? like i said, i dont want to damage them by putting the wrong size props on.
I should have put in the subject , I AINT GOT A CLUE lol
I should have put in the subject , I AINT GOT A CLUE lol
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RE: which props are recommended
Thanx jaka, but on which engine would they be for ? .15 .21 or the .25 ?? i think i am what they call a newb to this sort of thing ??
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RE: which props are recommended
Control line planes in the .15 to .35 size range need a decent amount of speed to be maintained to keep good line tension and control authority. There is no point in getting started in C/L with an engine prop combo that compromises the planes' ability to maintain line tension. If you want to start out slow, use the .15 with either a 8x3 or 8x4 Master Airscrew prop on a plane with a fat airfoil. Save the 3 blade props for later when you become an accomplished Ginsu Masta of the stunt pattern and your plane and skill level is finely tuned enough to nurse a slow moving .40-.60 sized ship through the stunt pattern. If you insist on a 3 blader for the .15, try to find a 7x3. Most .21s that I know of are high revvin' engines that need a easy prop to turn, most will have a very narrow range of props that they will be happy with. you might find that a 7x3 or 7x4 three blader is all a .21 will turn with any sort of willingness. The AMA might still have a chart that shows recommended engine / prop / applications, though last time I saw that chart, it seemed like it needed some updating.
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RE: which props are recommended
Ok thanx for the tips , I should have said at the begining There are 3 rules to this project.
1: Engines must be under.30 .
2: 3 bladed props must be used .
3: The aircraft can not resemble what we know as an aeroplane.
1: i have engines already
2: i can have and do need help with
3: I can not have any help with
perhaps speed will help, therefore i need 3blade prop sizes for the 3 engines i now have,
Every bit of help (prop sizes) will be greatly appretiated
Thanx Rick
1: Engines must be under.30 .
2: 3 bladed props must be used .
3: The aircraft can not resemble what we know as an aeroplane.
1: i have engines already
2: i can have and do need help with
3: I can not have any help with
perhaps speed will help, therefore i need 3blade prop sizes for the 3 engines i now have,
Every bit of help (prop sizes) will be greatly appretiated
Thanx Rick