Upper Engine Cowling, Part 2

With the top and bottom halves of the cowling mostly completed and the NACA ramp temporarily installed, it was time for additional work on the upper cowl.  First up was the fabrication of the oil cooler inlet duct.  Although I did not take any initial or intermediate pictures of the mold-making process, what is documented is the "aftermath" of the removal of the mold from the fiberglass duct.  It is not a pretty sight.  Below are a few shots of the 3 inch diameter CAT hose that was hand-held into position in the lower cowling and then "strapped" with duct tape to hold its shape.  It took both sets of hands of me and my wife to complete that wrestling process which hopefully explains the lack of photographic evidence.

Even though the duct tape was thoroughly coated in paste wax, there was no easy coaxing of the hose from the curved, cured surface of the fiberglass duct.  As a result, the CAT hose had to be carefully destroyed by pulling the wiring reinforcement to free it from the fiberglass.  I guess it would be obvious to other clever folk that it was coming out no other way.

A shot of the finished duct and its semi-destroyed mold...and then a shot of the duct itself.

Alignment marks to show where the ellipse will be cut from the lower portion of the upper cowl.

A rough mockup and check of dimensions of the duct/oil cooler/cowl fitment.

A head-on shot of the assembly...and a few others.

Next, the ellipse (cylinder intersecting a plane for you math majors out there) was approximated and transferred to the cowl and then the cutting began.

A few shots of the duct work poking out of the upper cowl...

The trim line is marked on the duct, where it intersects the cowl.  Once it is temporarily glassed into the cowl, it will be trimmed and then the intersection filled and sanded to finish...I hope.