Tip for making small panel patches

[scherp69]

I know there are lots of great fabricators and body guys on this site, none of which would ever need any advice from a guy like me, but I thought I would share a tip a discovered today,all because I was lazy the other day.

This is for anyone who had a hole in a panel that they needed to fill in with more sheet metal. I'm sure a lot of us have sat there cutting and testing, cutting and testing until finally the filler piece is the right size. Sometimes it may take several attempts, but eventually we make it. Today I was doing some more work on smoothing my firewall now that I now I will be using a drive by wire throttle. I cut out the area I wanted to smooth and started looking at the hole I had to fill trying to figure out the best way to make a template. I happened to look over on the floor and saw a roll of masking tape that I was too lazy to pick up the other day and it gave me this idea.

I thought of taking pics after I had the tape on, but you'll get the point.

The area I wanted to fill in was the pedal holes to the left of the steering column hole.

https://static1.pt-content.com/images/pt/2009/06/PICT00424-1.jpg

Once you have the hole cut, cover the entire hole with masking tape.

https://static1.pt-content.com/images/pt/2009/06/PICT00445-1.jpg

I used an exacto knife to cut along the sides of the hole

https://static1.pt-content.com/images/pt/2009/06/PICT00454-1.jpg

I then stuck the newly cut piece of tape to some sheet metal giving me my template

https://static1.pt-content.com/images/pt/2009/06/PICT00465-1.jpg

If you cut it along the side of the tape, it will be the about the same size of the hole. Since I wanted to butt weld it, I cut a little smaller than the tape

https://static1.pt-content.com/images/pt/2009/06/PICT00474-1.jpg

Take the tape off and you have your patch

https://static1.pt-content.com/images/pt/2009/06/PICT00484-1.jpg

Tack it into place. The nice thing about trimming a bit smaller than the tape was it left me nice gap to fill in with weld

https://static1.pt-content.com/images/pt/2009/06/PICT00493-1.jpg

Finish your welding

https://static1.pt-content.com/images/pt/2009/06/PICT00503-1.jpg

And finally after some clean up

https://static1.pt-content.com/images/pt/2009/06/PICT00515-1.jpg

[oestek]

That is a good trick. Saves time over cutting a piece of cardboard, trimming it, transferring the design to steel, trimming it, seeing that it doesn't fit, trimming more, then getting it right.

[dhutton]

That is a great tip. Thanks.

[Damn True]

You know those moments in life when you see something and think, "geez I am such a spaz, why didn't I think of that?". I'm having one of those right now.

Great idea man.

Sticky material.

[Bjkadron]

Looks good! great idea!

[parsonsj]

I've done this myself, and it is a good way to transfer a "void" to a piece of sheetmetal. Nice writeup.

One comment about putting a gap in the patch panel. You're right that it makes getting full penetration welding a lot easier, but it also puts stress on the patch and surrounding sheetmetal. When the weld is applied, the metal in the joint is liquid. As the joint solidifies, it shrinks, and pulls the metal edges closer together. In a firewall, it won't matter, but on exterior sheetmetal it will cause warping.

jp

[Damn True]

So when filling for instance, a side marker light, you'd want the tightest fit possible between the patch panel and the fender?

[parsonsj]

So when filling for instance, a side marker light, you'd want the tightest fit possible between the patch panel and the fender?Exactly. The welding is harder, since more heat is needed to get full penetration, which means you need to take more time when welding. Watch and make sure the metal edges stay lined up, take your time, and work in a methodical way. It will make a big difference in the amount of distortion you induce.

jp

[67SS]

What a easy solution...i trim, fitup, and trim some more. Great idea!

[Gearhead Dude]

That's a great idea! Thanks for the tip.

[gearbanger]

Man, this is the best tip I have gotten in a long time. It came at the most opportune time too! I have been patching all the holes in my firewall for a smoother look, like the old electrical bulkhead, and the grommet holes and so forth. This tip works far better than any other way you could do it.

Thanks for the tip scherp69 and thanks Pro-Touring.com!

[Jim Nilsen]

Don't forget to buy one of those welding magnets with all of the angles on it. You use the magnet to hold the piece flush while you tack it in. These things are priceless and come in many sizes.

[camaro2nv]

Dont forget these bad boys!
http://www.eastwood.com/intergrip-panel-clamps-set-of-4.html

[Greg from Aus]

Dont forget these bad boys!
http://www.eastwood.com/intergrip-panel-clamps-set-of-4.html

Awsome little tool I use them all the time.

Greg

[BigBlockOlds]

Dont forget these bad boys!
http://www.eastwood.com/intergrip-panel-clamps-set-of-4.html

I have set of those and they work really well. Bought them from Eastwood. However, after seeing that my local Harbor Freight sells the same dumb things for $5 I'll never spend the ridiculous $30 that Eastwood wants for them. Especially when you get 8 instead of just 4.

[67 ls1 vert]

:twothumbs Harbor Freight :hand: Eastwood.
exactly

[John Wright]

I have set of those and they work really well. Bought them from Eastwood. However, after seeing that my local Harbor Freight sells the same dumb things for $5 I'll never spend the ridiculous $30 that Eastwood wants for them. Especially when you get 8 instead of just 4.
Do you happen to know what the HB product number is or what name Harbor Freight gives these doodads....didn't see them on their site while searching

[BigBlockOlds]

I haven't been able to find them on their website either. I just happened to see they carry them in their retail store once when I was in there.

[bigblockcamino]

I have lots of panels like this can you come do em for me .... ;)

[67 ls1 vert]

Do you happen to know what the HB product number is or what name Harbor Freight gives these doodads....didn't see them on their site while searching
I was just at HF the other day and I seen them in the welding section. Plenty in stock.

[Draginutz]

Here you go $10 for 4. Not as good a deal as HF but I couldn't find them from HF online.

http://www.northerntool.com/webapp/wcs/stores/servlet/product_6970_200381757_200381757

[ironhide]

I just thought I might add a little trick . Before you notch down that weld on a warped panel . Get yourself a hammer and dolley . Hit just the weld . The weld is the only thing that shrunk . You can also use a few tack welds to shrink up an area if it "oil cans" .

I love the tape templates ! Great post

[67 ls1 vert]

Great tip. :idea:


What I do to is hold a piece of metal behind the hole you need to patch or repair and use a can of black paint and lightly fog over the hole. This will leave a pattern on the new piece behind the hole. Then you cut along the paint line.

[LSXfan]

definitley a "why didnt I think of that " idea..spray paint is also a very good idea....excellent tips !

[brans72]

Spray paint?

[H2Ogbodies]

great tip! I do a lot of electrical experiments and through that I became aware of super strong rare earth magnets and those are what I use to keep small patch panels tight and flush while butt-welding. They work great too!

[64impala]

Great Tip!!!!! Thanks so much

[427camaro]

Have always used the tape method, never thought of spray paint. Another great way of getting it done.

[cadwiz]

One thing I suggest is instead of sharp cornes use round ones as much as possible. You produce less heat in round corners then you do in sharp corners of patch panels.

[ammoyer]

One thing I suggest is instead of sharp cornes use round ones as much as possible. You produce less heat in round corners then you do in sharp corners of patch panels.

Exactly. Round those corners off and don't be shy. Think about how the corner piece of the lasagna is always more done than the casserole that's cooked in a round dish. That hard corner is subject to a lot more heat than if you round it off with at least a 1/2" radius.

Another point that someone brought up is to hammer and dolly the weld seam. After you weld that piece in, dress the weld till it's about flush with the patch and surrounding surface. The heat affected zone (HAZ) is where all the shrinkage has occured. On firewalls and floors where there is lots of shape and contour to maintain strength, the shrinkage will be almost unnoticeable. On surfaces that are flatter, the shrinkage will cause oil canning. Hammer and dolly on the seam only to stretch that HAZ back to a more relaxed state. Careful not to stretch too much, because you can go too far the other way. Firewalls and floors are great places to practice this technique for more delicate, flatter panels.

[AusMarty]

Literally just seeing that tape idea has opened my eyes.

I thought metal work would be harder than I thought to make weird shaped patches, but if you are using a light gauge metal, you can get a rough shape by shaping the new metal over the damaged/rusted metal, then use the tape method after cutting a patch section to transfer the shaped metal in.

That is just a way I thought of doing it just then, and I am sure there are more "professional" ways out there.
But that just solved one of my little brain barriers. lol

[renegade6]

I wish I would have seen this idea about 20 years ago. I knew about the paint one.

[Poncho72]

i have used the paint method before, but never thought of the tape method. i think its a better way to go. here's another if not mentioned before, use small magnets to hold the panel in place while tack welding only, but remove them after as they will disrupt the electrical wave pattern and mess up your weld.

[rizzo]

nice work (smashin my head)

[indyjps]

Another quick tip, get a foot of pipe in several diameters, weld a flat plate to it to clamp in your vice. Quick hammer forms for putting some shape into a patch.

I also ground, filed 3 1 foot long sections of the edge of my welding table to different radii. 1 sharp, 1 medium, 1 large. Makes real quick bending simple with a couple clamps and gradual hammering.

I have a couple of hardwood 2 x 8 sections with male or female "beads" router'd into them. Work well to replicate the form when patching. I use flat plates ground to radii, welded to a short pipe, hit with a hammer to form. Pipe has a slot ground in, with the plates slipped into the pipe before welding. You don't strike these very hard, Gradual forming into the beads, making sure it lines up.

trusty piece of railroad rail about 18 inches long, has different shapes on each corner, my town had a large railroad repair yard for about 70 years, so there's a lot of this stuff around, not sure where to get it now.