A few days back when I installed the radios the first time, I had a devil of a time getting the transponder to seat in its tray. I finally got it in and correctly seated after playing with it.
It was very, very hard to install the transponder. The comm radio was a little better but something was clearly amiss.
I posted my question on the VAF forums and received a number of replies. In fact, Stein called me and told me to try a few things.
Using their guidance, because I was not satisfied, I spent the day disassembling the radio stack. When I finally removed the VHF radio and the transponder and examined them, it was obvious why, they were so hard to install or remove. There were rub marks on the side of both near the faceplate. Both were rubbing on the protrusions (caused by stamping the lightening holes) on both the left and right stack angles (F-1202J-R/L).
I used a punch and a hammer and carefully bent the protrusions back. Then filed them flat with a vixen file and primed all of my scratch marks. With the trays not yet installed I was then able to slip both the transponder and the comm radio thru the panel without any side rubbing. (This was with the trays removed).
I also filed a small notch (1/8" deep) immediately below the transponder in the panel for cam clearance. Reinstalled the trays and used four 0.025" shims on each side on the comm radio tray as it is about 0.050-0.060" narrower than the transponder.
Inserted the transponder and it slid right in. Same for the comm radio. Both were sucked right in to their final position using the cam.
Stein was right, in that, one should be able to remove the radios with finger pressure if everything is aligned.
The protrusions in the stack angles were most definitely the major contributor to my original problem.
Thanks Stein, and the rest that replied to my original question on the VAF forum. Problem solved!!
Time Today - 6 hours
