Stick Welding Thin Sheet Metal

What's the watertight aircraft rivet? I think it has 'red' in the name...

Spot welding stands out as a good idea to me. The Horror Fraught spot welders are pretty inexpensive and work well. I ended up buying both the 110V and 220V versions, and found the 110V preferable (not as likely to burn through on the thin material I'd actually spot weld). I know it sounds stupid to buy a welder, but you could easily spend as much on good rivets...

GsT
 
With this style, the hole is filled with the mandrel:

You can also buy caps that drive into the hole like these:

Ted
Thanks, Ted. It's good to know that those are available. I will not be using any variety of pop rivets. This project will either be welded or riveted with real rivets.
 
The lathe that I bought recently doesn't have a backsplash so I need to make one from mild steel. I by far would prefer to stick weld this project. Gas welding is my only other option at home and I don't want to gas weld this project. The AC welder is an old Lincoln, so old that it has copper windings. It only goes down to 40 amps. I have very limited experience stick welding anything thinner than 1/8" thick. I would like to use 20 or 22 gauge to keep the weight down; 18 gauge is an option if 20 or 22 is too thin. I don't see a backsplash needing a lot of structural strength. I can bend the backsplash in a sheet metal brake but the ends will be welded on. I'll also bend a self for tool holders and other small items from the same material. I'm thinking 4 " wide on the shelf.

What is the lightest gauge steel that is reasonable to weld at 40 amps with 1/16" 6013 with a reasonably good chance of not blowing through? Is there a better rod than 6013 for this application?
I use to do custom body work with my Lincoln (a Hobby), sounds like you have the same machine. You can successfully weld 16 and 18 ga with it, the trick I used was A) use 1/16" (or 3/32" if you find 1/16" to be elusive) 6011 rods, B) clamp a thick piece of metal, Aluminum works best within an 1 or so to either side of the weld and C) stitch it a half inch at a time until you have it joined. This controlled blow through and warp-age very well. It also helps if you can overlap the 2 pieces as opposed to a butt weld.
 
What's the watertight aircraft rivet? I think it has 'red' in the name...

Spot welding stands out as a good idea to me. The Horror Fraught spot welders are pretty inexpensive and work well. I ended up buying both the 110V and 220V versions, and found the 110V preferable (not as likely to burn through on the thin material I'd actually spot weld). I know it sounds stupid to buy a welder, but you could easily spend as much on good rivets...

GsT
Watertight is not a priority for me. Spot welding would be nice but I'm not buying a spot welder to use once. If I put a rivet in every 2" starting one inch from the ends I'll need 24 rivets. I can get 1/8 pound of rivets for under $7.00. One eighth pound is 435 3/32" or 216 1/8" by 3/16" long rivets.
 
I use to do custom body work with my Lincoln (a Hobby), sounds like you have the same machine. You can successfully weld 16 and 18 ga with it, the trick I used was A) use 1/16" (or 3/32" if you find 1/16" to be elusive) 6011 rods, B) clamp a thick piece of metal, Aluminum works best within an 1 or so to either side of the weld and C) stitch it a half inch at a time until you have it joined. This controlled blow through and warp-age very well. It also helps if you can overlap the 2 pieces as opposed to a butt weld.
Thanks for the on-topic answer! I bought some Hobart 1/16" 6013 rods yesterday at Tractor Supply. The backsplash on my Grizzly is not welded solid so I see no need to weld this one solid either. The calculated weight difference is 28 pounds for 18 ga and 35 pounds for 16 ga so I think 16 ga is a viable option. The outside dimensions will be about 24" tall and 58" long so I don't want to make it too awkward to handle. By overlap, are you thinking to bend an "L" on the end caps? I have a nice big block of aluminum to use as a heat sink. I'm going to get small pieces of 18 and 16 gauge steel to see what I can successfully weld.

Edit: BTW, the welding instructor said that "if I was good enough" I should be able to weld 16 gauge so that's just more reinforcement that I might be on the right track.
 
By overlap, are you thinking to bend an "L" on the end caps?
Exactly, the edge to edge or butt weld for me is difficult as I want to put too much too quick and make a mess of it while the "L" or an overlap is much better as you have a double thickness. I use to put a narrow strip behind butt joints for this very reason.

The block of aluminum for a heat sink helps control warpage...
 
Back
Top