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e015475 · 08-08-2018, 12:17 PM

Overlapped joints is just looking for trouble., Joints should be butt welded. If you don't the repair will telegraph through the paint, and it will certainly rust a lot quicker at the repair

Having a back up strip may not produce the finished product you want. The metal is going to shrink when you weld it. and to get it back to contour you are going to have to planish the weld to stretch the metal back out. This is going to be pretty hard to do with a backup strip in the way

Trim the patch panel first then use a sharp scribe to transfer the joint onto the old truck sheet metal. Cut to the scribe line with a cutoff wheel in a die grinder. Make adjustments with a sanding disk on the die grinder and make the final fit with a file. The more perfect the joint, the less metalwork you'll have to do.

Even if you are very experienced, cutting with tin snips will distort the metal causing it to curl at the edge.

Cutting the two panels together ensures that you are off at least the kerf width of the cutoff blade.

Do a precise scribe off of the patch panel and cut the metal square with a wheel. Grind and file to fit. Sneak up on the fit and take your time. The time it takes to make a near perfect fit, weld it and metal finish it is less than all the metalworking it takes to get a sloppy fitting joint to look ok with metalwork.

If you gas or tig the joint and have proper tacks, you can pretty much weld continuous bead, the weld that is proud of the metal will be easy to grind flush and there will be less work to planish the weld.

08-08-2018, 12:17 PM	#26
e015475 Registered User Join Date: Nov 2013 Location: Show Low, Arizona Posts: 761	Re: Cab corners Overlapped joints is just looking for trouble., Joints should be butt welded. If you don't the repair will telegraph through the paint, and it will certainly rust a lot quicker at the repair Having a back up strip may not produce the finished product you want. The metal is going to shrink when you weld it. and to get it back to contour you are going to have to planish the weld to stretch the metal back out. This is going to be pretty hard to do with a backup strip in the way Trim the patch panel first then use a sharp scribe to transfer the joint onto the old truck sheet metal. Cut to the scribe line with a cutoff wheel in a die grinder. Make adjustments with a sanding disk on the die grinder and make the final fit with a file. The more perfect the joint, the less metalwork you'll have to do. Even if you are very experienced, cutting with tin snips will distort the metal causing it to curl at the edge. Cutting the two panels together ensures that you are off at least the kerf width of the cutoff blade. Do a precise scribe off of the patch panel and cut the metal square with a wheel. Grind and file to fit. Sneak up on the fit and take your time. The time it takes to make a near perfect fit, weld it and metal finish it is less than all the metalworking it takes to get a sloppy fitting joint to look ok with metalwork. If you gas or tig the joint and have proper tacks, you can pretty much weld continuous bead, the weld that is proud of the metal will be easy to grind flush and there will be less work to planish the weld.