Building Tips

Cowl Alignment and Mounting -- the easy way;

By; Pat Tritle, courtesy of TreeDiver


        One of the more difficult tasks in scale modeling is setting up the cowl alignment for mounting. I was looking around the E-Zone ( the other day and happened to spot this method for cowl mounting that TreeDiver has been using for awhile and was so impressed I asked him if it would be OK to post up the idea for others to use. It is with his blessings that we proceed.

    The first problem usually encountered in mounting a cowl is centering the prop shaft in the opening and keeping it centered while the mounting screw holes are located and drilled. This method is so simple, I don't know why even the Wright Brothers didn't use it on the original '03 Flyer -- oh wait, the flyer didn't have cowls?? Well anyway, the key to this slick little method is a simple foam disk fitted into the prop shaft opening in the cowl and slipped over the prop shaft to keep it the opening centered while the cowl is being fitted to the fuselage (or nacelle for twin and multi-engine configurations). Here's how it works;


Items required to get started;

A-    3 or 4 MM Depron foam or Artists Foam Board (the kind used for making bowed outline patterns).

B-    A measuring device used to determine the the diameter of the cowl opening

C-    A compass, or drafting circle template to size the disc to fit the front cowl opening.

D-    A sharp knife to cut the disc from the foam sheet.

E-    The appropriate size drill bit to drill the disc for the prop shaft.


Begin by measuring the opening to determine the size of disc required. A caliper works best, but

a ruler or drafting circle template will do nicely as well.

Draw the proper diameter circle on the foam and mark the center point of the disc.

Using a compass the center hole will be clearly visible. If you use a drafting circle

template you'll have to find the center after the circle is drawn.

 Cut the disc out of the foam and drill the center hole. Now you can fit the disc into

the opening in the cowl, trimming as needed for a good snug fit.

With the disc fitted into the cowl, slip the cowl assembly onto the prop shaft and align

it on the fuselage. Drill the mounting holes and screw the cowl in place. And finally,

remove the disc and the job is done.

Building Tips