Cowl Jig and Panel Cuts

I'm going to be bouncing back and forth between the cowl and other work for a while, just because that's the only way that I'll keep my sanity while working with the cowl.  I can't remember if I posted a picture of how the cowl jig works.  Basically, the black 3D printed spacer is bolted to the prop flange and sets the appropriate distance for the front of the cowl.  The disc gets attached to the front of the cowl and slides over the center dowel to ensure the cowl is consistently placed every time it comes off and on (which I'm assured by others will be at least 100 times).

I spent a few hours trimming and sanding the front edge of the top and bottom cowl.  They still don't fit together, but at least it's a little bit closer.  Many more hours of trimming to come (followed by a lot of additive fiberglass after it's all said and done to fill in spaces and mismatched surfaces).  I was running out of room to work, so I put the top cowl in place just to get it out of the way.  It's starting to look like a plane!

Change of scenery - back to the panel!  The other day I had gotten the big hole drilled for the Garmin G5, but still needed to drill 3 screw holes around that for mounting the attach bracket.  The bracket gets screwed to the panel and then the G5 slides onto it.  The unit has a pin on the back side at the top that slides into the bracket as a reference point, then it's made solid by screwing in a small allen head screw from the front.  Thankfully, all of my measuring paid off, and all of the screw holes landed in the right places to make the G5 set square.  Every other instrument in the center stack will reference off of this, so it was pretty important to get it right.

Next up was the radio and autopilot panels.  Those will flank either side of the G5.  Because the G5 does stick out from the panel, I decided to bump the radio and AP panel out 1/4" from the edges of the G5, just to give me a little more room to reach everything without feeling like I was having to work around the G5.  Laying this out involved a ridiculous amount of measuring and double checking squareness.  It doesn't help that the shapes of the panels are odd (at least they're both the same).

I pulled out the die grinder and went to town.  This is thick aluminum, so it took a little longer than I anticipated to make the plunge cuts each time.  I started hand filing the AP panel (right), but ran out of steam.  I'll continue with that next time.  I'm sure I'll have to sneak up on the lines a little at a time to get the fit right.  I need to order mini nutplates that can fit in those tiny corners.  That's what the units will screw into.  Thankfully, there's about a 1/16" lip on the units, so the cutouts will be hidden and don't have to be perfect. The important part will be getting the nutplates in the perfect position to make everything square.  now I see why people often get the panels cut by CNC.  It would definitely take some of the anxiety out of layouts.  Really though, these top three devices are the worst of the bunch.  Otherwise it's just a bunch of big rectangles and circles.