Noob question here... hopefully my last. I'm cutting out a section of my floorpan to weld in a new piece from a doner car. My problem is I noticed that there are a bunch of ceramic pieces attached to the floor itself. They don't look incredibly sturdy and just kind of chip off where it's weak. Do these serve any purpose? On all of the videos I've seen on floorpan welding, they don't even exist. What is this?!?

 

Are you talking about the sound deadening material? It's black and covers alot of the floor. In some places it can be soft since it's made of rubber.

 

Yes! Thank you! Now should any removal / prep be done to it for welding? What's the general practice?

 

remove the tar from around where your going to weld (or remove all of it, its like 30lbs of tar) then grind the metal down to bare metal for your welds.