Brief Description: Fabricated doubler for battery & starter relays.
I completed the fabrication of the F-7127D doubler which will be riveted on the aft side of the firewall to allow bolting the master and starter relays to the forward side of the firewall. I had to drill out 2 rivets from the firewall that holds one end of two platenuts. These platenuts will hold one end of the battery relay and the other will hold one end of the starter relay. I also had to drill the bolt holes for those platenuts which were 1/4". Two other #40 holes were drilled for the other ends of the platenuts. Although not really difficult to do, I had a little trouble accurately drilling the bolt holes and had to slightly elongate the holes through the stainless steel firewall and angle stiffner to properly accept the bolts into the platenuts. We riveted the platenuts through the firewall, aluminum angle, and platenuts. We used AN426AD3-4.5 rivets and riveted with the rivet gun and bucking bar.
As I said, not difficult but tedius and easy to make a mistake if you don't study the drawing enough. Tommorrow we'll match drill the doubler to the firewall and rivet the doubler and platenuts. The firewall has to be machined countersunk to accept the flush rivets since it very difficult to dimple. The doubler bolt holes accept bolts for the other ends of the relays.
F-7127D doubler fabricated from 0.063 aluminum sheet.
Platenuts riveted to aft side of firewall through the angle stiffeners.
