Bare metal between spot welds?

[hudson hornet !]

What is the best method for protecting the bare metal in places such as pinch welds? Doing a restoration and I do not want rust down the road. Thanks for any help.

 

[Chad.S]

I epoxy them before putting them together, and grind out the area at the weld so you don't have to weld through the epoxy, I haven't been able to come up with any better methods.

 

[dhutton]

I use 3M weld thru primer.

Don

 

[MP&C]

If you are plug welding, epoxy prime both parts inside and use modified bit to clean off paint inside plug weld holes once they are clamped together and weld. If you are spot welding, epoxy prime both parts inside, mock up and mark for spot weld locations and clean paint off per the following:


In order to use the spot welder along the bottom seam, we needed to clean off some epoxy primer where the spot welds would be located. Used and even spacing of 2" and marked both flanges...

In order to remove as little epoxy primer as possible, we decided to use the modified plug weld drill bit (the flattened one) over all the errant marks a roloc sander would make. In order that the flat drill bit didn't walk all over the place, another specialized tool was made....

Here's another close up of the modified bit...

this is the same size drill bit I used for plug weld holes is flattened and backfaced to resemble an end mill cutter.

.....and the "prepped" flanges...

Flanges spot welded together...

Prep remainder and epoxy the outside...

 

[67fastbackgt]

Those pliers are awesome

 

[hudson hornet !]

Thank you guys for the help. I will be using the methods you described. If a new part has e-coat, should it be removed or can I epoxy over it?

 

[Bob Hollinshead]

You can scuff it and epoxy right over it. On restoration stuff I remove the e-coat at least on the exterior-sometimes both sides. Sometimes the quality of the e-coat is poor or there is rust below and just not worth the gamble on some projects.

 

[hudson hornet !]

Thanks. My sheetmetal is from Auto Metal Direct. I have been happy so far with the quality, but I think I will check under the E-Coat.

 

[Senile Old Fart]

The pliers are a great hack! Used with an end mill bit they would make a great poor mans Spotle .

 

[DATEC]

Where did the green epoxy come from?

 

[Outlaw]

I epoxy them before putting them together, and grind out the area at the weld so you don't have to weld through the epoxy, I haven't been able to come up with any better methods.

Chad, do you spray those areas or brush it on?

 

[anotheridiot]

we started using weld thru on this project, but there are still areas between what is not being removed that you really cannot get at. I get that if the epoxy covers it properly and no oxygen or moisture can get to the rust it should not be able to break thru again, but its hard to believe.

 

[MP&C]

The green epoxy is house of kolor. When they went well over 300 for a two gallon kit I changed to SPI, and haven't looked back. IMO Barry has a much better product..