RCU Forums

RCU Forums (https://www.rcuniverse.com/forum/)
-   Seaplanes (https://www.rcuniverse.com/forum/seaplanes-176/)
-   -   prop size (https://www.rcuniverse.com/forum/seaplanes-176/11210383-prop-size.html)

m-mtoys 08-29-2012 09:24 AM

prop size
 
I am putting a 55 AX engine on this plane,but not sure what prop to use in a 3 blade or 4 blade.

The engine calls for a 12/7 or 8 13/6or 7 Not space for a two blade prop. Carey

JimCasey 08-29-2012 02:26 PM

RE: prop size
 
Use the same pitch for a 3-blade and drop the diameter by 10%

Lamoilleriver 08-29-2012 03:27 PM

RE: prop size
 
Had no idea they are making 4 bladed props.

Laird SS 08-30-2012 01:58 AM

RE: prop size
 
Biela makes 2, 3, and 4 blade props in many different size/pitch combinations. They also have some pusher props. The material is carbon fiber with a wood hub. All the props are balanced individually just before they are put out for sale.

In the interests of full disclosure: I do not work for Biela, nor do I receive anything from them for any sales that they may get from my comments.

jaka 09-12-2012 11:30 AM

RE: prop size
 
Hi!
What kind of strange animal is it that cannot take a two blade prop??

ronwc 09-13-2012 04:39 AM

RE: prop size
 
11 x 7 three blade

m-mtoys 09-13-2012 01:31 PM

RE: prop size
 
It is a Balsa USA Laker plane

Mustang Fever 09-13-2012 03:41 PM

RE: prop size
 
What's the biggest prop you have room for?

I have a pair of 55AXs on a B-25. I finally settled on 12x6 MAS 3 blade props. These let the engines turn about 10,500 rpm on 15% Cool Power, good for around 60 mph and gobs of thrust. They never liked any of the various two blade props I tried, including the ones recommended by OS.

jaka 09-14-2012 03:17 AM

RE: prop size
 
Hi!
I'm certain that if you tried some Graupner Sonic or RAM...or even APC props in the range of 12x6,13x4, 13x5 you would see better performance than those 12x6 3-blade MA props.

Mustang Fever 09-14-2012 06:54 AM

RE: prop size
 
It's hard to find a lot of info on the Laker, it's an old Laddie Mikulasko design from RCM Magazine. The listing on RCM plans calls for a 40-46, and I'd bet that Laddie put that engine pod down low so that an 11" prop is probably as big as you can go.

You might want to think about a 46AX, or even electric power. I used a Turnigy G46-670 turning an MAS 11x7 3 blade on five cells in a Mikulasko "Arrow" flying boat, and it wails. The nice thing about electrics in "pod engine" flying boats is that the battery pack makes it a lot easier to balance the dang things. They really want to come out tail heavy.

LADDIE 09-14-2012 07:12 AM

RE: prop size
 


ORIGINAL: m-mtoys

I am putting a 55 AX engine on this plane,but not sure what prop to use in a 3 blade or 4 blade.

The engine calls for a 12/7 or 8 13/6or 7 Not space for a two blade prop. Carey
If there was no modification done to the kit, then 12” prop will fit nicely. The model does not need any larger props.
Laddie.

Mustang Fever 09-14-2012 09:22 AM

RE: prop size
 
Nice to hear from the source!!


I'd go with the 12x6 MAS 3 blade, then. I find that the 55s in my bomber run a very long time on 11 oz of fuel with that prop.


All times are GMT -8. The time now is 05:54 AM.


Copyright © 2024 MH Sub I, LLC dba Internet Brands. All rights reserved. Use of this site indicates your consent to the Terms of Use.