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Weld through primer
BenB - 15/1/09 at 02:32 PM

Has anyone experience of the U-pol weld through primer?

What I'm trying to work out is why they made it zinc based when generally zinc is considered the boogy man, welder's fever etc etc etc.....

Is weld-through as good as no weld-through??? IE does it have any impact on the welding???

What are the advantages of using it? Just that you can prime something even if you need to weld it later? You'll presumably still need to spray the top coat once it's all welded up so why not just prime at that point?!?! Confused

Still bought some though!!!!

Mr Whippy - 15/1/09 at 02:39 PM

the black coating on body repair panels is also usually weld through. Its really meant for working outside in the rain and damp and most good garages don't need this. Unless it takes years and years to build your chassis. I don't like the zinc bit, been very sick before from it

Mark Allanson - 15/1/09 at 07:03 PM

quote:
Originally posted by Mr Whippy
the black coating on body repair panels is also usually weld through. Its really meant for working outside in the rain and damp and most good garages don't need this. Unless it takes years and years to build your chassis. I don't like the zinc bit, been very sick before from it



The black coating on new panels is transit primer

Only bodgit back street garages don't use it

It is essential as it prevents rust forming in the closed area between spot welded panels, it is for this purpose that it has been designed

You only get zinc fever from galvanised panels, and usually only hot dip

Mr whippy, on this occasion 0/10, see me in breaktime

Canada EH! - 15/1/09 at 07:12 PM

I painted my rear axle with the primer after removing the stock mounting brackets and before welding on the Locost ones. No problems, no real smell, and no side effects. Welded one year ago, no rust in the area of the welds either.

Peteff - 16/1/09 at 10:50 AM

The black coating on replacement panels is cataphoretic primer for keeping them presentable till they are sold. It isn't weld through but it is so thin that it burns off as you weld.