when to sandblast?

[beater_k20]

i got my SAS brackets today for my '92. i'm planning on sandblasting and painting the frame before it gets swapped under the truck. i'm thinking clean the areas to be welded up with an angle grinder and a few roloc discs, preassemble everything, then get it welded up, strip the suspension back off of it, and then paint and reassemble.

anybody see anything wrong with this? (other than its more work) will it weaken my welds any?

 

[b454rat]

Don't see how it could weaken them any. Clean metal will weld alot better than rusty or dirty metal....But, let's see some pics!!!!!

 

[AussieK5]

I just had my frame and tub sandblasted. I'd sandblast first, it gives you good clean metal that will go a long way to ensure your welds are not contaminated and therefore weakened. I'd paint everywhere, but where you are welding first. Once done prep the surfaces as you normally do and your as good as gold.

Blasting after its done works as well, I just like having clean parts to start with. Sanblasting wont weaken any welds, if anything it may (and thats MAY) help with reducing instances of micro cracking, just like shot peening of rods.