Go Back  RCU Forums > RC Airplanes > Seaplanes
Reload this Page >

prop size

Notices
Seaplanes Aircraft that typically take off and land on water...radio control seaplane discussions are in here.

prop size

Old 08-29-2012, 09:24 AM
  #1  
m-mtoys
Junior Member
Thread Starter
 
Join Date: Aug 2007
Location: Detroit, MI
Posts: 9
Likes: 0
Received 0 Likes on 0 Posts
Default 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
Old 08-29-2012, 02:26 PM
  #2  
JimCasey
Senior Member
My Feedback: (1)
 
JimCasey's Avatar
 
Join Date: Mar 2002
Location: Lutz, FL
Posts: 1,957
Likes: 0
Received 1 Like on 1 Post
Default RE: prop size

Use the same pitch for a 3-blade and drop the diameter by 10%
Old 08-29-2012, 03:27 PM
  #3  
Lamoilleriver
 
Join Date: Dec 2005
Location: northern, VT
Posts: 261
Likes: 0
Received 0 Likes on 0 Posts
Default RE: prop size

Had no idea they are making 4 bladed props.
Old 08-30-2012, 01:58 AM
  #4  
Laird SS
Senior Member
 
Join Date: Apr 2005
Location: Peoria, AZ
Posts: 603
Likes: 0
Received 0 Likes on 0 Posts
Default 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.
Old 09-12-2012, 11:30 AM
  #5  
jaka
 
Join Date: Dec 2001
Location: Upplands Vasby, SWEDEN
Posts: 7,816
Likes: 0
Received 3 Likes on 3 Posts
Default RE: prop size

Hi!
What kind of strange animal is it that cannot take a two blade prop??
Old 09-13-2012, 04:39 AM
  #6  
ronwc
My Feedback: (404)
 
ronwc's Avatar
 
Join Date: Jan 2002
Location: LARGO, FL
Posts: 501
Likes: 0
Received 0 Likes on 0 Posts
Default RE: prop size

11 x 7 three blade
Old 09-13-2012, 01:31 PM
  #7  
m-mtoys
Junior Member
Thread Starter
 
Join Date: Aug 2007
Location: Detroit, MI
Posts: 9
Likes: 0
Received 0 Likes on 0 Posts
Default RE: prop size

It is a Balsa USA Laker plane
Old 09-13-2012, 03:41 PM
  #8  
Mustang Fever
Senior Member
My Feedback: (2)
 
Mustang Fever's Avatar
 
Join Date: Nov 2003
Location: Cadillac, MI
Posts: 3,225
Likes: 0
Received 1 Like on 1 Post
Default 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.
Old 09-14-2012, 03:17 AM
  #9  
jaka
 
Join Date: Dec 2001
Location: Upplands Vasby, SWEDEN
Posts: 7,816
Likes: 0
Received 3 Likes on 3 Posts
Default 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.
Old 09-14-2012, 06:54 AM
  #10  
Mustang Fever
Senior Member
My Feedback: (2)
 
Mustang Fever's Avatar
 
Join Date: Nov 2003
Location: Cadillac, MI
Posts: 3,225
Likes: 0
Received 1 Like on 1 Post
Default 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.
Old 09-14-2012, 07:12 AM
  #11  
LADDIE
 
Join Date: Jul 2004
Location: Dundas, ON, CANADA
Posts: 207
Likes: 0
Received 0 Likes on 0 Posts
Default 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.
Old 09-14-2012, 09:22 AM
  #12  
Mustang Fever
Senior Member
My Feedback: (2)
 
Mustang Fever's Avatar
 
Join Date: Nov 2003
Location: Cadillac, MI
Posts: 3,225
Likes: 0
Received 1 Like on 1 Post
Default 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.

Posting Rules
You may not post new threads
You may not post replies
You may not post attachments
You may not edit your posts

BB code is On
Smilies are On
[IMG] code is On
HTML code is Off


Thread Tools
Search this Thread

Contact Us - Archive - Advertising - Cookie Policy - Privacy Statement - Terms of Service -

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