Go Back  RCU Forums > RC Airplanes > Kit Building
Reload this Page >

Moving Back a Firewall

Notices
Kit Building If you're building a kit and have questions or want to discuss kit building post it here.

Moving Back a Firewall

Old 01-02-2015, 02:51 PM
  #1  
Homer712
Thread Starter
My Feedback: (17)
 
Join Date: Apr 2010
Location: New Market, MD
Posts: 190
Likes: 0
Received 0 Likes on 0 Posts
Default Moving Back a Firewall

I'm just getting started with this winter's build, a Jack Stafford Aircoupe (by Leisure RC Models), and although the laser cutting is incredible, the kit is an old kit and the plans/instructions leave a lot to be desired (I've built a good number of kits over the years, Goldberg, Top Flite, Balsa USA, Sig but those all have three photos for every step, this one is pretty much glue/cover/fly, so I think it'll take most of the winter to just figure things out).

But back to the firewall. The plans (one sheet, and I'm not sure how close "to scale" it is) shows the distance from the front of the firewall to the back of the engine backplate as 3 1/2". When I mount my Saito 62 I have a firewall to engine backplate of 4 3/4". Sounds simple enough, move the firewall back 1 1/4". Is it really that simple? If it is, it'll be the first simple thing I've ever come across in this hobby. Advice anyone? Anything else that needs to be considered? Balance point?
Old 01-02-2015, 03:44 PM
  #2  
Leroy Gardner
 
Join Date: Jun 2009
Location: Idaho
Posts: 2,285
Likes: 0
Received 6 Likes on 5 Posts
Default

Homer the balance C.G. does not change moving the fire wall back. Best way I found to move a fire wall is redraw where it needs to be on the plans. Mount or standoffs need to be on the engine, then set it on the plan so the back of prop is 1/16" ahead of the cowling or the place its shown on the plans. Square the engine up as close as possible and mark the back of the mount on the plans, that will be the face of the new location of the fire wall.

Leroy
Old 01-02-2015, 07:00 PM
  #3  
foodstick
 
foodstick's Avatar
 
Join Date: Mar 2005
Location: ankeny, IA
Posts: 5,574
Likes: 0
Received 7 Likes on 6 Posts
Default

Some people will move the entire firewall back, others counter sink a box..
I even know of guys that will leave the firewall alone and move the cowl forward a bit and build in between the two...

I would take into consideration mostly how the access to your motor is affected for upkeep and adjustments..
Old 01-03-2015, 12:35 PM
  #4  
chip_MG
My Feedback: (14)
 
Join Date: Feb 2009
Location: austin, TX
Posts: 143
Likes: 0
Received 0 Likes on 0 Posts
Default

Any of those will work.. As long as the CG is right it should fly fine. Where the fire wall is at makes little difference.

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 - Do Not Sell My Personal Information -

Copyright © 2022 MH Sub I, LLC dba Internet Brands. All rights reserved. Use of this site indicates your consent to the Terms of Use.