DIY Chatroom Home Improvement Forum

DIY Chatroom Home Improvement Forum (
-   Metal Fabrication (
-   -   Help Needed Metalworking Question (

roof5244 08-04-2018 01:03 PM

Help Needed Metalworking Question
3 Attachment(s)
Hello All,

I'm working on 18 ga. sheet metal project where a stamped recess in the sheet metal has become distorted and flattened (no recess). I would like to know how I can restore the recess back into the sheet metal. The recess dimensions are approximately 1 1/8" x 1 1/4". I've attached photos showing the damaged flattened recess and an undamaged recess. Any help is appreciated.

thank you

Nealtw 08-04-2018 04:39 PM

Re: Help Needed Metalworking Question
That might be tricky, and I know nothing.

de-nagorg 08-04-2018 05:33 PM

Re: Help Needed Metalworking Question
As Neil shows, auto body repairmen do that a lot, but they have experience and training.

A power tool is made for this, It is a mechanical hammer tool, where the power is created by you stepping on a pedal, which causes levers and wheels to lift the hammer, and releases the hammer to pound on the sheet, repeatedly step, pound until it is formed to your satisfaction.

That sheet looks similar to an exhaust gasket, can't you just get a new piece from someone?


Gregsoldtruck79 08-04-2018 07:07 PM

Re: Help Needed Metalworking Question
This is what I would. Use at your own risk. JMO

KHouse75 08-05-2018 01:05 AM

Re: Help Needed Metalworking Question
Looks like a ford. Possibly a 60s mustang. A hammer and dolly will fix that. Study some youtube videos on classic car sheet metal repair.

Nealtw 08-05-2018 04:50 AM

Re: Help Needed Metalworking Question
I think I would cut 2 pieces of 1/2 steel the shape of the recess and bolt them together with a 3/4" bolt and work the steel round that from the back side.

PSCampbell 09-30-2018 12:39 PM

Re: Help Needed Metalworking Question
Using a hammer and dolly or hammer and stump will correct this problem. Be careful not to hammer the metal too thin or you will have a crack.

GVS 02-11-2019 07:14 PM

Re: Help Needed Metalworking Question
4 Attachment(s)
I'm a metal fab guy. There's a few ways you can go about this with some pretty basic tools - I'll assume you have at the very least an angle grinder, welder and some crap steel laying around somewhere?

The best way is to create a backing template to form the piece back into it's original recessed shape. If you can't cut one out with a plasma cutter or torch, then just use some scrap steel and put them together. Or cut strips with a grinder and weld them into one piece, if you don't have smaller band stock? When you but them against each other for joining, grind them at a slight angle - doesn't need much - and then put your weld into that little valley between, then grind it flat for stacking and clamping down later. Don't try to make beefy welds. This is a temporary piece, you'll likely toss it when your done with it. So don't make it perfect - minimize. It's important to roll the edges where it's needed for a curve as the 18 ga recesses down - before you weld it together. If you have a smaller air grinder, you could cut out a square hole easily and skip all that. Don't worry about the cut lines criss-crossing in the corners of your template if you do make a one piece template. But if it really bugs you, then you can weld them shut and grind them flat. Just thinkin' out loud on how to make the template, that's all.

The idea here is make a mold pattern for your recessed area to follow, as you hammer form it back inward. You should have 4 layers clamped down to your table to do this.

1)The top plate with a square access hole to hammer and hold the outer edges down on your 18 ga sheet metal, it can't move.
2) The 18 ga piece you wish to form.
3) The template piece your 18 ga metal will form into. Make sure the sides are as tall as the depth of what you want the piece to be. Account for the thickness of the 18 ga steel too. That's also important with the sides as well. Don't make it exactly the same size as your piece. It should be the thickness of the metal, larger. So the metal can form to the correct size. Otherwise you will force it inward and shrink it and create excess material that needs more forming to lay properly.
4) The blacking plate. This piece will give you something to work against and stop your hammer - be gentle with hammer or you will expand the 18 ga steel. If your work table is a fairly thick steel top, use that instead as you clamp it down.

Start hammering (tapping) around the outside, in a circle, very lightly. You may not think you're doing anything, but you are. TAKE YOUR TIME. Work in a spiral inwards, when you get to the middle, Start over, in the opposite direction, and alternate each time. No over lapping, no zig zagging with the hammer pattern until the end. Between two of these hammer cycles, heat it up with a torch. Even a pipe solder torch on high will work fine. Heat in a spiral also, but from the inside outward. You don't need it red hot, or even sizzling hot. Kind of a med sizzling I guess - too hot to keep your hand on it but only that. All you want to do is relax the metal molecules after you've made them rigid by hammer. It's called 'annealing' if you'd like to look it up first? Once you get it there, have a small block of wood or steel handy (with a softened corner or curved edge if you use metal) to stamp the outside where your hammer couldn't reach. That'll clean up your corners. This is the crash course, but hopefully it helps. In a bind, if you had some hardwood you might be able to make your pattern with that too. But I wouldn't with 18 ga.

If you have a hydraulic press, you could just make top and bottom templates and press-form it in that way too.

Another other option is to find a donor, cut it out and replace yours with it. Some welding and grinding required, but only if you're good at welding thinner steel without warping it? If you were nearby, I'd say bring it over! But hope this helps get the ideas flowing for you? I tried to draw out a visual because I'm more a hands on teacher than typing out instructions. Hopefully you can make sense of it. I was in a hurry and need to get going so no time to proofread all my babble. Just wanted to put my 2 cents in before I left. Good luck, be sure to let us know how it turned out?

This might help you also:

All times are GMT -5. The time now is 07:26 PM.

Powered by vBulletin® Version 3.8.8
Copyright ©2000 - 2019, vBulletin Solutions, Inc.
User Alert System provided by Advanced User Tagging (Pro) - vBulletin Mods & Addons Copyright © 2019 DragonByte Technologies Ltd.
vBulletin Security provided by vBSecurity v2.2.2 (Pro) - vBulletin Mods & Addons Copyright © 2019 DragonByte Technologies Ltd.