Drilled avionics mounts
Drilling the avionics trays to the mounting angles is a slow process. I did a lot of measuring and careful alignment. I used some .063 under the bottom tray for two purposes. First, the Garmin transponder has a cam at the bottom of the unit for securing it in the tray. If you mount the tray too close to the bottom of the opening, it’ll be tough to insert and remove. I also wanted to make sure there was no visible gap at the top of the stack.
Some people recess the trays so the bezels of the units don’t stick out so far. I went with the standard mounting. I made the front edge of the tray flush with the surface of the panel. I marked and drilled the trays one at a time, but I probably could have done them all at the same time. I drilled to #40 and then to #28 for #6 screws.
It looks like two of the trays use countersunk screws and two use pan head. Crazy. I temporarily installed countersunk screws in all of them just to test the fit. The SL40 fit great with one #6L washer on each side. There’s some slop in the PMA-8000B mount, but I’ll nail that down once I get the GNS-430 GPS. The stack looks really good. Now to cut the subpanel…
