Platenuts on wing ribs

[RVG8tor]

I have to mount the controller for my Dynon pitot, I want to attach it to the rib inside the bell crank inspection plate. The rib in this bay had the curve for the lightening holes and indentations to the inside. My idea is to attach platenut to the rib, then with one washer between the control box and the rib face, this will lift the box up enough that it will not interfere with the raised parts of the rib. So will these holes compromise the integrity of the rib? Have seen some rivet a bracket to the rib that the controller then gets attached to, it just seems to me that I really don't need the bracket. Sorry for not having a picture, my wife has the camera today. Thanks for any advice.

Cheers

[Noel Simmons]

Just make sure you do get the spacers between the rib and the box correct. This is also a nice technique to use if you still have riveting to do. I have always been concerned with the shock of riveting on small electrical boxes and the fact of accessing a bucking bar around these little boxes.

[jthocker]

Why not just mount the controller onto the access cover like I did.
I didn't use the existing holes in the controller. Instead I used a single flush nutplate on either end and dimpled the access cover.

[RVG8tor]

Originally Posted by Noel Simmons

Just make sure you do get the spacers between the rib and the box correct. This is also a nice technique to use if you still have riveting to do. I have always been concerned with the shock of riveting on small electrical boxes and the fact of accessing a bucking bar around these little boxes.

I was actually not thinking of riveting nuts onto the electrical box, but riveting the plate nuts to the ribs. But when you mentioned this it got me to thinking, I wanted to mount the box on the raised side of the rib for access in case I ever had to remove the thing, but this would require a spacer. Well if I rivet the nut plates onto the electrical box then I don't need a spacer because I then set the box on the flat side and run the screw through the rib and into the nut on the box. I will not be able to see the box as it will be on the outboard side of the inspection hole, but I will have access to unscrew the thing, which is all I need.

Does this seem OK? I end up with 4 holes in the rib, that the screw runs through into the nuts riveted onto the control box, this will pull the box tightly up against the rib.

Cheers