Cockpit substructure, Thinking about drilling a hole through it Options

[Randal]

Thinking about drilling a 3/4 inch hole through the firewall to an Accusump on the other side. The Accusump will sit facing backwards towards the cockpit firewall mounted where the seat normally goes.

Anyone ever drilled through this section.

There is a black arrow where I want the hole.

All advice appreciated.



BTW I'm going to cover up that higher hole where the lines used to run to the front cooler.

[McMark]

To expand on what Chris said, that area is a boxes section. So where the arrow is you would have to drill through one layer of sheet metal, and then drop into the box and drill through the next layer into the cabin.

If you drill though the dimple, those two layers of metal are back to back. But there a spot welds in the dimple. I imagine this was done for structure to tie those pieces together. If you remove the spot welds and don't compensate for it (weld around the circumference of your drilled hole) you're taking that structure away. It's probably not going to affect a caged car like yours all that much, but I'm not a big fan of it.

If I were doing it here, I would drill through the box section, then weld in a tube to make a sealed hole in the body. Then feed AN line through the hole and add the ends on after.

[SirAndy]

If I were doing it here, I would drill through the box section, then weld in a tube to make a sealed hole in the body. Then feed AN line through the hole and add the ends on after.

Like so:

(IMG:http://www.914world.com/bbs2/uploads/post-179-1151215319.jpg)

(IMG:http://www.914world.com/bbs2/uploads/post-179-1175805981.jpg)

(IMG:http://www.914world.com/bbs2/uploads/post-179-1175806021.jpg)

(IMG:http://www.914world.com/bbs2/uploads/post-179-1175806054.jpg)

(IMG:http://www.914world.com/bbs2/uploads/post-179-1175806091.jpg)

(IMG:http://www.914world.com/bbs2/uploads/post-179-1176965977.jpg)

(IMG:http://www.914world.com/bbs2/uploads/post-179-1177645190.jpg)

(IMG:http://www.914world.com/bbs2/uploads/post-179-1182813892.jpg)