15x8 is to big for the plane, how to pick a replacement?

Hi all,

i have posted about this problem yesterday, but i think i was a bit vague about what the real problem is. So i here go again:

My Graupner Trainer 65 has a Laser 100 4-stroke engine, those little cuties are recommended with a 15x8 propeller. But in this case there is not enough ground clearance.

From center of the propeller nut to the ground, there is 8 inches! I can get another ½ inch by using larger wheels.

What propeller sizes would you recommend i try out, to replace a 15x8?

Happy landings, Henrik Denmark

PS: I do have a rev counter, just not sure if it is any help for this.

Reply to
Basil
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Try a 14X8 or 14X10.

Reply to
Paul McIntosh

It's gonna be faster with the props Paul recommends. Maybe different (higher) landing gear? Dr.1 Driver "There's a Hun in the sun!"

Reply to
Dr1Driver

What about a three bade prop. Don't know what size to suggest, perhaps a 13 x something

Regards

Tom Watson Sydney Australia

Reply to
Tommy

Jeeeeeeeeeeees if this is your trainer what would you have as a pattern ship.

Vic

Reply to
The Shaw's

Go down on diameter, up on pitch.

OTOH you could extend the nose wheel/gear a bit - might get an inch extra ground clearance that way. Cheers, Fred McClellan the dash plumber at mindspring dot com

Reply to
Fred McClellan

hehehe :-)

methinks i'll wait a bit with one of those. But the Laser is surely going pull it around once i get that far. I got the plane with RC-gear and the Laser for the price of the kit alone. Almost finished and never flown. I'll never understand why he parted with the engine, but i surely wont complain :-)

Happy landings Henrik

Reply to
Basil
14 x 8 three blade.
Reply to
jeboba

Thanks guys.

I'll go roam the shops to see if they have any 3-blades, before i attack the nose wheel. It is one of those steerable ones, so i would prefer not to fiddle with it right now. I want to flyyyy :-)

Thanks again Henrik

Reply to
Basil

I fly .40 sized Sig Kougars a lot. For the last 15 years I have been pushing them with Saito .50's and .56's. I found they worked best if I lengthened all the landing gear legs 1 inch. For the .56 the 11X8 props work, but the 12X7 work better. I sold the .50 but I used 12X6's on it so the 1 inch was needed.

It does not take that much work and is worth every minute of it!

-- Jim Branaum AMA 1428

Six_O'clock_High Target snipped-for-privacy@Guns.com

Reply to
Six_O'Clock_High

Try a three-blader, you can probably get away with a 12inch diameter if you do, but I can't help with the pitch. An E-,mail to Neil Tidey at Laser should help, though.

Reply to
David Smith

Hi Ron

It warms me to tears to find that the RC people are so wonderfully helpful. You are so kind.

Happy landings, Henrik

Reply to
Basil

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