Plug or seam weld?

[Mike1973]

Just taken an outrigger off the Kombi, which is spot welded to the chassis and top hat. I was going to drill a holes in the new outrigger and plug weld it into place, following the original spot welds, but all the photos I have seen of outriggers being replaced show beads of welds run along the seams where it joins. Why is this? Is is easier/quicker/stonger? Or is it just personal preference? I've never welded in anger before, this'll be my first job on the Vdub!
Cheers folks,
Mike.

 

[malcolm]

The big advantage of plug welding is for where you have a couple of bits of metal joined by a folded flange. I've made a pic below of a couple of horizontal bits of metal and a vertical flange. The forces will run through the horizontal bit of metal so the weld needs to be as close as possible to that.

The blue plug weld is a lot closer than the red seam weld, so plug welding would probably be better in this case.

If you had two bits of overlaping sheet then a seam weld would be stronger (as there's more of it).

Your top hat is halfway inbetween the two cases. Seam welding would probably be stronger, and would have the advantage of sealing the joint from water.

 

[Mike1973]

Cheers Malc :wink:

At the moment putting the new outrigger in seems like it will be easy compared to taking the rotton one out :shock: Never had to dismantle anything on a vehicle before so it's all new to me, but got there in the end. Hammer and chisel and grinder did most of the work, the special drill bit for doing the spot welds wasn't much cop though.

Just going out now to rust treat all the hidden metal I've exposed before I fit the new outrigger tomorrow.