Mounting a Chin Cowl
by Don Ramsey

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When mounting a chin cowl I like to use three 440 screws, one on the front of the cowl and one on each side of the cowl back.  I use a post in the fuselage with a blind nut to capture the screw and a piece of dowel in the chin cowl to support the screw.  The trick is getting the post and the dowel to match perfectly.  You could do it by trial and error but there's a better way.  How about installing the parts as a unit and then gluing it in. Since it's installed as one unit nothing can go wrong, go wrong, go wrong.  

The photos are of a Rhapsody with a nomex fuse, that's the reason the dowel extends through the chin cowl.

First, cut a post and install a piece of dowel in the chin cowl.  I make the post out of 5 ply plywood.  Hold the two pieces together and drill a hole for the 440 screw.  Insert a blind nut in the post and temporarily screw the two pieces together (the 440 screw will be countersunk in the finished product and yes, it should have been countersunk first).  Use the mated pieces to mark and cut a hole in the fuse.  Make the hole large enough to allow some adjustment but not so large as to require a lot of glue.

Mark and cut a hole in the fuse


Slide the post on the chin cowl into the hole and use masking tape to hold the cowl in place.  Use  a lot of masking tape  to insure a good fit.  Remember, the finished product is only as good as the fit here, so make it right.

The Collar

Make a collar out of light ply that fits the post.  Through the canopy opening slide the collar over the post and epoxy in place.  Once the epoxy is dry cut off the excess post material and re-glue.  Simple, quick and a perfect fit every time!

View from inside the fuse.  Cut off the excess post material (I use a Zona saw)

The finished Product 
View of the 2 rear post 
that hold the chin cowl.  
Blind nut visible on left post.



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