I have garrett t3/t4 that needs the exhaust housing welded. My question for everyone is about the preheating procedures. My plan was to used some 7018 or er70s tig rod, but I don't know about the preheat. All I need to do is fill in the 1/8" hole in the picture. I've heard cast needs to be preheated to like 350, if this is the case can I place it in the oven for an hour and then weld it?

 

yep cast needs to be heated to like 350-400 degrees before being welded

 

if you ever plan to make anthing in your over to eat evr again I wouldn't recomend using your oven. Though an oven is the perfect tool for the job.

 

Try a grille

 

Good call on the grille. That means I really need to go get the propane tank filled, because now it's a neccessity. Thanks for the information.

 

Yes - it is much, much easier to weld if you preheat it.

I have a cheap-@ss $20 used oven that I use for everything from pre-heating cast stuff for welding to powder coating. Its on casters and has a table top on it, so it really doesn't get in the way at all. I push it out and plug it in when I need it.

I have also used those IR heaters that sit on top of a propane tank. Just hang whatever you are heating from a metal wire and check it with a laser thermometer.

Best of luck with your project.