Structural body adhesive. Any experience, or advice?

[scotts74birds]

Hi guys. I'm doing this on my Ram, but the knowledge crosses to our B-bodys. I have a 97 Ram that I am replacing the left-rear wheel-arch. The plan is to cut the body, and use a home-made flanging tool to set the recess on the body. The patch is a Sherman part, about 1.2mil. The flange tool we made is about 1.7mil to allow for adhesive depth, and the natural "spring-back" of the metal.
We set the flange length at 3/4". I will be using self-tapping screws for clamping, in pre-drilled holes.
How far apart should these screws be? There will be some stitch-welding of the panel after the adhesive to provide additional mechanical bond. I'm not very good at welding, so my goal is to keep it to a minimum.
All advice is welcome

 

[Photon440]

Since you have the welder, why not practice for a couple of hours on similar patches until you're confident that you can do it that way?

However if you're going to glue it, and I'm guessing you mean something like Eastwood's No-Weld panel adhesive, or 3M automix 2-part adhesive, then you'll want the screws a couple inches apart. If you do a dry run and find any particular part isn't tight, you can add another one in that spot right away. Your 3/4" flange is about right, most times a minimum of 1/2 is mentioned, but no more than 1 inch.

If you do it this way, I wouldn't follow it up with the stitch welding as you mentioned, as the heat will damage the adhesive. The glue is pretty strong on its own.

 

[scotts74birds]

I'm using Evercoat panel adhesive. And thanks for the advice! I wish I was experienced at welding thin metal However I feel that my welding skills are not at the level to take the chance with this. I don't weld, I make holes and big piles of metal at this time.

 

[Northwest]

I have used the 3m product on a panel patch about 5 years ago, as well as a couple of other awkward to weld repairs. What I have learned is the best results come when the panels to be bonded are shaped well beforehand and clamped TIGHTLY to achieve the best bond. The product does not work pulling metal together that wants to spring apart, or if the gaps to be bonded become too large so my advise is to work the pieces to match well. Also you cannot over clamp the 3m stuff because it contains very small glass beads to set the adhesive . I wouldn't weld anywhere near it once cured.

 

[2fuzy]

the welding is really not that hard to do as you make very small welds the trick is not to get carried away in a hurry
You are not trying to run a pefect bead you are basically making a bunch of tack welds