type of join when welding rust patches?

[Jason]

So after I cut out the rust infected area I would like to weld in some patch metal (First time doing this) do I butt join the patch to the car or do I put the metal behind or infront?

Any insight would be great, thanks.

-Jason

[Ian]

Experts performing a concourse restoration would probably butt-weld the patch. I'm not that good at welding yet, so I've chosen to overlap the patch by about .5" and run a flange around the patch piece to stiffen the patch. I did this by cutting a piece about 1" larger all around, and laying the patch over the hole from the inside. From inside I traced the outline of the hole, and trimmed the patch down to .5" larger than the hole, and used a flanging tool to run a flange all around. I held the piece in place with sheet metal screws, and either welded the holes shut when done, or used blind-sealing rivets. I placed the patch inside, and welded inside and underneath the car.

Ian

'76 M2 (patched, hopefully not leaking anymore!)

[Ian]

For a side patch, where everything will show, I'd butt weld the patch.

Ian