White Cowl

[Doug]

I built an inside flange on the lower cowl in west systems epoxy and glass matt then mounted 3 #8 nutplates on each side riveted directly to the new epoxy flange. (2 1/4" ext) The flange fits the top very closely and to some degree the cowl halves are keyed together. A lot of heat re-forming was necessary beforehand to get a good fit between the halves.

200 hours and still looks as good as new, very happy with this solution.

I was aware of some local builders having the aluminium plates work loose or break so chose a different solution. I can imagine these plates would fail if they were also being used to drag the halves into alignment.

But, save 15lbs and make the job much easier - spring for a new cowl.

[revenson]

Originally Posted by az_gila

Thanks Roger, but you didn't have the early white polyester cowl did you?

Gil: Oh, maybe not. I thought there had only been two cowls. All I know is that mine is not the new pink one.

[rocketbob]

On the old cowling I had the metal plates crack more than once and also had rivets work loose. I suggest going with a piece of stainless .080 thick and also use epoxy/milled fibers along with soft rivets to attach the plate to the bottom cowl.

Also milled fibers on the top half would be helpful in keeping flex down...in other words tape the plate once its attached then lay up the epoxy and milled fibers on the back side of the top flange so you always have a flat surface against the plate. With the screws and nutplates in place of course.

[az_gila]

Thanks for all of the info guys.

I think I will combine both approaches - I will make a fiberglass tab and then rivet an aluminum plate with the nutplates onto it, making sure there is a flox layer filling any voids. I like the idea of #8 rather than #6 screws though.

I also discovered the power of a heat gun in shaping the white cowls. I trimmed the inner edges, made a ring clamped to the spinner location and used clamps to hold the cowl halves in position.

Note the before and after pictures - and I thought I was going to have to cut it along the dotted line and slice in a triangle of new glass...

[AJ85WA]

This brings back so many memories! I did this last year and kept some record of it. have a read, might help a bit http://rv6aj.wordpress.com/2013/01/28/cowl-fitting/

Keep building mate, it is so worth it!