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Back again. I’m just completing a 150% T-Bird and have gotten my hands on a nearly new K&B .19 for power. Not having experience with power models I’m at a loss in sizing the prop. I would like to hear your suggestions.
And while we’re talking props, how about my 1/2a T-Bird? I thought, incorrectly, that 6/3’s were the way to go. APC list smaller props for 1/2a free flight. Working from memory, 6/2, 5/3, 5.7/3 and maybe more. This would go on a strong Holland Hornet. What would you suggest.
Thanks for the help.
I have a K&B 19 Green Head Torp. in a 1954 Swiss Miss that has an 8×4 APC on it. Seems to be about right.
I still have a few 5×3 Cox gray props, that I find work well on the Cox 049/051s.
On the 19 8×4 0r maybe a 9×3 cut to 8.5
On the HH–if you can get the 5.7x 3 use it. 6×3 APC might be too much. A saw might be handy though.
A carpenter wpuld recommend a saw!! I would CNC machine it to the proper size….But then, maybe a hack saw is the proper way to do it…Luddite style..
Actually, I reduce blade diameter by easing the prop tips against against a brick. While the engine is running. Its more effective with a rich four stroke ‘stunt’ type needle setting. But I don’t recommend this technique to the faint of heart , nor the type who allow a computer to operate a machine!
Been there done that- I have used concrete, grass, dirt, a wooden work bench, glow plug wire, but have pretty well kept away from flesh….
If a machine cannot be run via a computer, what good is it?
A nice feature about those CNC machines. While they have no learning curve, they NEVER get tired or need a coffee break.
None of my flying machines need a computer, but then I only fly Free Flight!
I agree,human flesh doesn’t really help with reducing prop diameter.
I never tried glow plug wire.>human flesh doesn’t really help with reducing prop diameter.
Works well the other way, though .. says he with a forefinger 3/16″ shorter than the other .. and it was only a lowly TD.049!
You guys are having way too much fun with this.
I don’t think Jim Moseley’s story indicated much in the way of fun.
Perhaps you are correct. As I read the post I thought it was offered in jest as were the two postings that preceded it.
Thanks for the suggestions guys. The 5.7X3 and 8X4’s are on order.
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