Ken Powell wrote:

Paul,
I remembered that you mentioned the engine buildup without the insides once
before. I put a 'dummy' together last weekend.  I also ordered the landing
gear/motor mount for my RV-4 last week.  This should allow me to do a

complete

mockup of the firewall forward.  Thanks for the suggestion on the schedule 40
pipe - I didn't remember the size.  I am going to build the 'box' (which

has no

top or bottom, only sides) mentioned below out of 2 x 4 lumber with

gussets in

the corners to hold it square.

Ken Powell

That ought to work good. Your remaining problem is welding in awkward

positions

but it can be done of course. I fear the mount might pull out of shape if
I just tack it on the engine and remove it for final welding.
I have a warmer feeling if it is positively held in position during
final welding.

  It is a certainty that the mount will "move" when you weld it.  Not
possible to
keep extremely tight tolerences when you heat up to molten unevenly, like in
any normal welded truss structure.  You'll just have to live with some
distortion.
  The good news is that it is a LOT worse on something bigger like a fuselage.

Bill

 
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