How to dimple in the middle of an installed firewall?

sblack · #1 04-13-2019, 08:41 AM

I need to move my voltage regulator to the back of my firewall. The space available has the battery on the other side so I need to dimple for #6 or 8 countersunk screws. The question is how to dimple in the middle of the firewall? Is it possible?

Paul 5r4 · #2 04-13-2019, 08:48 AM

Yes, There is a set of dimple dies that work with a nail and pop rivet gun.

https://www.aircraftspruce.com/catal...?clickkey=6499

Christopher Murphy · #3 04-13-2019, 08:49 AM

You can buy tools for this if you didnt build the airplane. Or someone who did can help you do it. And if you are like us old timers, you can make your own.

Cm

bhester · #4 04-13-2019, 08:53 AM

Pop rivet dimple dies:
http://www.cleavelandtool.com/mobile...s/products/48/

Kyle Boatright · #5 04-13-2019, 08:58 AM

http://www.vansairforce.com/communit...=Dimpling+tool

mturnerb · #6 04-13-2019, 09:55 AM

Another option I’ve used is to drill a hole that fits the female dimple die into a steel bucking bar, hold this inside the hole, then use the rod from a c frame dimpler with the male die. A helper holds the female die/bucking bar and a firm hammer strike on the rod holding the male die (nested with the female die through rivet hole) sets the dimple.

sblack · #7 04-13-2019, 11:22 AM

Quote:

Originally Posted by Kyle Boatright

http://www.vansairforce.com/communit...=Dimpling+tool

Ah that's perfect! Thanks.

sf3543 · #8 04-13-2019, 12:30 PM

For a one off tool to do a few holes, you can just get a scrap piece of 1/8 or thicker aluminum and drill the appropriate hole for your selected screw.
For a #6 screw, drill a #36 hole in the scrap, countersink it (a little oversize countersinking works best) and then tap the threads.
Drill the #28 hole in your firewall and then screw through that into the dimple die you just made. Screw it in tightly and it will dimple for your screw head.
Van's, or someone, used to sell a tool similar to this to dimple spars on the older kits for #8 screws.

sblack · #9 04-13-2019, 12:44 PM

Quote:

Originally Posted by sf3543

For a one off tool to do a few holes, you can just get a scrap piece of 1/8 or thicker aluminum and drill the appropriate hole for your selected screw.
For a #6 screw, drill a #36 hole in the scrap, countersink it (a little oversize countersinking works best) and then tap the threads.
Drill the #28 hole in your firewall and then screw through that into the dimple die you just made. Screw it in tightly and it will dimple for your screw head.
Van's, or someone, used to sell a tool similar to this to dimple spars on the older kits for #8 screws.

That's another great idea. Thank you.