Spot weld cutting

Well, as you can see from the picture below (taken a few weeks ago) my framehead bottom plate is in a sorry state, particually on the drivers side. Just look at the size of that rust scab!

 

Thankfullly the rest of the frame head seems pretty solid so I have decided to cut off the whole bottom plate and replace it with an aftermarket panel. I will then clean up the rest of the frame head, which should only need minor repairs (if any). I am keen to retain as much of the original metal work of the car as possible and figured I would salvage the brake line brakets and graft them onto the new panel. I have heard that the ones that come attached to the replacement panel are flimsy and utterly crap, so I think this will be worth the little extra effort. I have circled them in red below:

Flipping the pan back over I started out by wire brushing the area below the brackets and then lightly sanded to reveal the location of the spot welds. As you can see there are 3 distinct spots under each bracket which needed to be drilled out:

 

This is the spot weld cutting bit for my drill that I opted to use. Basically I used a centre punch to create a dimple in the middle of each spot weld then placed the spring loaded guide pin (the protruding part you can see on the left of the photo) into the depression:

Working with the drill on a slow roatation I steadily cut through just the top layer of metal:

 

Then gently separeted the bracket from the old panel:

 

 

I then clamped the piece into a vice ready for grinding down the excess weld material:

Here is the piece after grinding. Now it just needs cleaning up and a quick lick of paint to keep it from rusting until the time comes to attach it to the new panel:

Now that I am practiced in the art of spot weld cutting I better crack on and drill out all the little buggers that are holding the bottom plate in place...