RV-12 Lower Cowling (ULS)

[dsm8]

The lower cowling is clamped in place. Right side looks pretty good, may be a little trimming. Left side of by 18/32" at the top and 16/32" at the bottom. Pretty sure the left side as trimmed along the scribe line.

Any thoughts and suggestions are welcom3

https://photos.google.com/share/AF1Q...NPbWprUzc2MFZB

https://photos.google.com/share/AF1Q...NPbWprUzc2MFZB

[scottmillhouse]

I see you do not have the engine mounted. STOP now and ignore the cowling until you get the engine and prop mounted. I don't think the scribe lines are consistent. If I used mine, my left side would have been cut over 1/4" too short. You may be lucky and you did not cut too far.

With engine installed shim and clamp to align lower cowl to spinner with 1/8-3/16" gap. Use the method for other RV cowls. Mark a line on your fuselage 1" or so back so you can overlap cowl. Support and tape cowl into position and transfer your mark to the cowl. Cut outside the line in increments. Work slowly to get a good fit. If you have already cut too much, just lay cloth to build edge back up to past when needed, cut and repeat.

[Tony_T]

I agree with Scott 100 percent. There is absolutely no up-side to trying to fit the cowl before the engine is installed. After you have the spinner back plate for reference you can position the cowl starting from the front spinner alignment, then mark the sides to fit the fuselage as Scott says.



You will save time and get a better fit after the engine is in place.

[Cyclone]

Wait until engine is mounted and you have a spinner to aim at. I had a perfect fit using the scribe lines and being a rookie builder, followed that up with a perfect paint job on the cowling....only to find the cowling was 1/2" off centered from the spinner AND the plenum required drilling a bunch of holes thru my shiny paint. So it was moving hinges, filling holes and some new paint.
Not the first learning experience I've had and am still having fun

[RFSchaller]

Yep, I put the engine on and agonized on the cut lines only to find out the scribe lines were a near perfect requiring only minor sanding of the edges for a perfect fit.