Painting firewall

[59pacer]

Engine's out for overhaul, so it's time to clean the firewall and brag a bit.
After making a simple jig, and careful marking out, it took a whole afternoon with discs, oil, and a big drill.

DSC07544.jpg

[Broncoformudv]

That sure came out sharp looking!

[walt.buskey]

Man, I hate the way you guys make me drool!

[smcnutt]

Engine's out for overhaul, so it's time to clean the firewall and brag a bit.
After making a simple jig, and careful marking out, it took a whole afternoon with discs, oil, and a big drill.

DSC07544.jpg

Looks familiar but I like it.

[Glen Geller]

Engine's out for overhaul, so it's time to clean the firewall and brag a bit.
After making a simple jig, and careful marking out, it took a whole afternoon with discs, oil, and a big drill.

DSC07544.jpg

Hey 59,
I'm really curious about how this was done.
Can you post any pics of the jig in use, and a couple sentences about your procedure, tooling, and techniques please?
I'm probably going to get my engine rebuilt late 2021, so if I have a winter of an empty firewall, I'll have the engine mount, nosewheel mount and other stuff serviced and painted, and maybe glam up the firewall as you have done.

Thanks,
GG

[59pacer]

Hey 59,
I'm really curious about how this was done.
Can you post any pics of the jig in use, and a couple sentences about your procedure, tooling, and techniques please?
I'm probably going to get my engine rebuilt late 2021, so if I have a winter of an empty firewall, I'll have the engine mount, nosewheel mount and other stuff serviced and painted, and maybe glam up the firewall as you have done.

Thanks,
GG

No problem, but I'm just about to relocate to the hangar for a couple of days, so I'll get my thoughts together and post the info when I get back.

[59pacer]

.DSC07555.JPG
I decided on a new stainless firewall with 2" circles. Harbor Freight at the time had 2" diameter coarse scotch brite discs with a screw thread that I could capture in my drill chuck.
The jig was a piece of dressed timber in which I cut 2" diameter holes at 4" centres. It would have been quicker to use 2" centres, but I was sure that bits of wood would start breaking away and make things difficult.
I laid the old firewall on the new stainless which had been clamped on a stiff board, aligned the centreline of the firewall with one edge of the stainless sheet, drilled a few locating holes, and marked the outline for later reference.
The machining sequence was:
1 complete a row of circles
2.move up 1" and to the right 1"
3. complete the next row
4. move up 1" and to the right 1"
5. keep doing that until you're bored rigid and need a stiff drink or three
Mark both edges of the stainless with 1" graduations. Have an index line on the jig board and somewhere on the stainless so you can move the jig board accurately 2" and 1" to the right.
Clamp the jig board with reference to the marked sidelines. Put a few squirts of engine oil in the hole in the jig, put the disc in the first hole and run it for a few seconds. Move across doing the same at each hole. Move the jig 2" to the right, clamp, and do all those holes. You then have a single row of 2" circles marked on the stainless.
Now move the jig up 1" and to the right 1", and do all the holes, move the jig 2" to the right and fill in the missing holes.
Repeat until it's done.
If you decide to be a contrarian, you could go up and to the left, or start at the top and work down, but then you're committed to doing the whole firewall that way!
You'll need to experiment with how much pressure and for how long you run the disc. As it wears out, you'll need more time to get a similar effect. I think I used about 20 discs for the job. It's fairly messy with all the oil flying about, it killed an afternoon, but it was worth the effort.