I'm upgrading my roll bar to a full cage. Roll bar is welded on, new bits will be bolted onto the floor and existing bar.
Idea is to drill though the roll bar and weld a boss on on the tube side so its invisible.
Question is, how can I weld round the boss without destroying the powder coat too much?
If the part isnt safety critical that getting bolted onto the rollbar I think I would just tack weld it all the way round allowing it to cool between
each tack and also tie some wet rags around it too, maybe after each tack slide the wet rag down to cool it quickly.
Realistically its gonna get f&cked 
Wondering how difficult it would be use one of those powdercoating kits that I nearly bought at Stoney and a
heatgun would be?? At least it would all match...
Just re read it, if its the new cage thats going on, instead of tacks, short runs would the next step up but obviously more coating is going to
bubble, it will take a while but it'll get done in the end.
Best of luck mate
R
[Edited on 25/9/10 by RichardK]
I had to re-weld some brackets on a powder coated chassis and used a product call "Cold Front". This is a paste that is a very efficient heat sink and does actually work. It really did limit the area of damage to the paint caused by the welding.
If you are really that worried about the powder coat then don't weld it. There is no way you can totally protect it and it'll look pants
patched up.
So why not employ a scaffold clamp type setup instead. (designed to look much less bulky and ugly of course).
A flat strap 2 inch or 3 inch wide folded round a round bar say 8mm smaller in dia than the existing bar. then drill the new bar and weld in a solid
tube to run a bolt through. Bolt it up and the clamp does its job on the existing tube. You could also trim the new clamp edges or dress them round
the new bar where it clamps. Powder coat all the new gear and voila job done.
If it is for msa however then forget my idea
[Edited on 25/9/10 by omega 24 v6]
Dont cool a weld quickly, it can cause it to go brittle.
quote:
Originally posted by MakeEverything
Dont cool a weld quickly, it can cause it to go brittle.
If you are going to the trouble of building a full cage that may one day save your life, I think you should remove the powder coating so you can have a proper weld done with proper penetration by a professional welder.It is a necessity to have good clean bare metal to ensure a proper quality weld. Then you can paint it with a good quality paint. Dont take a shortcut when it comes to safety.