Firewall forward, finish, cowling progress

Red (Sharpie) circles on the inside of the top cowl were traced through the large, central holes in the Camloc flanges. One can readily see that few of the pilot holes were successfully drilled dead-center in those tracings.

Fortunately, it’s of no matter whatsoever since those pilot holes can be easily walked with the Unibit until they’re centralized within the red circles. Easy-peasy.

Nicely finished ½” holes ready for Camloc grommets. The Skybolt instructions call for 15/32″ holes except in areas where the grommets won’t fit, in which case one should upsize to ½”. For whatever reason, despite my cowling not appearing to be overly thick to my eyes, the grommets wouldn’t seat properly in 15/32″ holes, so up to ½” I went.

Camloc grommets installed and retained by the standard Skybolt retainers. They also include some O-rings to use as temporary retainers for guys who want to remove them prior to paint. I had them painted on my last RV and prefer that look to that of the bare stainless steel, so I went with the permanent retainers from the get-go.

Camloc studs installed in the grommets and ready for the first fitting to the receptacles now riveted to the flanges.

Fingers were definitely crossed here (and wood touched, too!) as I was holding my breath to see whether all of the studs properly engaged with their receptacles.

Success!! Every stud matched up with its receptacle and engaged properly. From that point, it’s just a matter of screwing them down until the stud is flush (or very slightly below) with its grommet. Then the locking pins come out, the receptacles are locked into place at the 1/7 orientation, and fit is reconfirmed.

All turned out perfectly. Despite being raring to go with the lower cowling, I need to order some Cherry rivets for the bottom flanges. So, tomorrow I’ll finish off the empennage fairing (some floxing to do in the corners and nutplates to rivet in place) and perhaps get started on the baffles.

Success!! Every stud matched up with its receptacle and engaged properly. From that point, it’s just a matter of screwing them down until the stud is flush (or very slightly below) with its grommet. Then the locking pins come out, the receptacles are locked into place at the 1/7 orientation, and fit is reconfirmed.

All turned out perfectly. Despite being raring to go with the lower cowling, I need to order some Cherry rivets for the bottom flanges. So, tomorrow I’ll finish off the empennage fairing (some floxing to do in the corners and nutplates to rivet in place) and perhaps get started on the baffles.

Firewall forward, finish, cowling continued…

Bottom flanges for lower cowling drilled and clecoed in place.

Bottom flanges for lower cowling deburred, countersunk, and clecoed in place for riveting. I strongly suspect that they’ll need to be pop-riveted (I’ll find some Cherry rivets which fit) due to conflict between the squeezer yoke and the engine mount.

Yes, I could try to grind down my no-hole yoke, but I’m not interested in sacrificing a $125+ yoke for this one-off task.

Bottom flanges for lower cowling deburred, countersunk, and clecoed in place for riveting. I strongly suspect that they’ll need to be pop-riveted (I’ll find some Cherry rivets which fit) due to conflict between the squeezer yoke and the engine mount.

Yes, I could try to grind down my no-hole yoke, but I’m not interested in sacrificing a $125+ yoke for this one-off task.

Upper cowling Camloc receptacles clecoed in place for riveting.

Upper cowling Camloc receptacles riveted to the flanges and ready for adjusting in conjunction with the studs.

Firewall forward, finish, cowling fitting in process

Skybolt’s cleco retainers stuck to strips of masking tape and ready to be set in place for drilling.

The first few cleco retainers taped in place.

I set one little neodymium magnet on the underside of the cleco retainer, dropped the another on top of the cowling, let it find its center, then drew rough crosshairs alignment marks around it, removed the magnets, and drilled.

I was able to immediately cleco perhaps 90% of them. The rest need to be walked a little, but no big deal; they’re all going to get opened up considerable for the Camlocs.

Top cowl drilling and clecoing underway…

Top cowl drilling and clecoing completed.

Firewall forward, finish, cowling coming along

Camloc flanges deburred, countersunk, and clecoed for riveting.

Camloc flange riveting underway.

Camloc flange riveting complete – along the firewall top and sides, anyway.

Upper cowling set in place again, now resting its aft edge largely on the Camloc flanges. A little sanding tomorrow, then mark and cut an ⅛” strip from the aft edge, then some more sanding (are you seeing a theme here?), and the upper cowl should be ready tape in place and drill for the Camloc grommets.

Upper cowling set in place again, now resting its aft edge largely on the Camloc flanges. A little sanding tomorrow, then mark and cut an ⅛” strip from the aft edge, then some more sanding (are you seeing a theme here?), and the upper cowl should be ready tape in place and drill for the Camloc grommets.