[Bob Ellis]

I would like to fit the cowl during the warmer months but my wiring is going to take much longer than I thought (underestimated the amount of pre-wiring prep required).

I have searched the forum and found the answer, which is yes, but not the how?

Did people 100% cleco the forward edge of the top skin from inside the firewall with just the tips of the clecos sticking out? Or is there a more fiendishly clever way?

Regards

Bob Ellis
www.rv-8.co.uk
90% done 90% to go!

 

[Pat Stewart]

Cowl fit

It is actually pretty simple. Cleco every hole in the fwd skin all the way around. Put the firewall clecos in upside down. A series of shims around the fwd skin clecoed underneath the fwd skin will help support the cowl during final trimming. Apply tape to the top of the skin 2 inches back and parallel to the fwd edge of the skin. Fit the cowl to the spinner back plate. Set your gap and install shims that match your gap between the cowl and the back plate. you can tape the shims to the cowl face. Make sure the cowl is in the correct position side to side as well. Measure from the tape fwd something like 1 3/4 or just far enough to clear the clecos and make a series of marks all the way around the aft edge of the cowl. Use that line as a guide only and trim the cowl just enough to clear the clecos and lay flat on the top surface of the skin. Place a strong light inside the cowl and use it to transfer the final trim line to the cowling. Trim to fit. If you start with the minimum gap at the back plate you will have more to work with during final trim just in case you need it. A small gap in the end looks good but will actually make cowl removal difficult and scratch your paint.

I'm sure there are many ways to do this but this is my method. remember measure twice trim once every time.

Pat

 

[Kyle Boatright]

I think I just left the cleco's across the top off until I got a rough (but generous) cut line for the cowl. Then I made the cut, fit again, cut again, lather, rinse, repeat, untl the cowl aft edge was far enough forward that I could reinstall the cleco's and trim to the final size/shape.

 

[RV8R999]

ditto what kyle did. The top skin and upper edge of the firewall end up flush with with other so you are really cutting the cowl to the skin as much as the firewall flange. Just cleco the top skin everywhere but the top fwd row of holes and it will be in its final position for cutting. At least this is how I did it.

 

[Bob Ellis]

Pat/Kyle - Perfect - thank you. Ken I think your phrase "so you are really cutting the cowl to the skin [top]" is the key for me - thanks.

 

[Dave Stephens]

I just used some soft Ali C/S pop rivets in every 3rd or so hole in the top skin around the bulkhead, fitted the cowl, then just drilled them out with an undersized drill. the come out realy easy

Dave