what gauge steel with mig welder

Post by **tag60** » Tue Aug 22, 2006 3:07 pm

hi all
please can any one help
i will be using a mig welder with 0.6mm or 0.8mm wire
i need to do a small repair to the front o/s inner wheel arch down by the bottom of the door and have been told they is no repair panel avallable. and to weld a plate in so the Question is what thickness plate to use?

the only other way round it as i can see would be to fit a full arch
which i am told is a very big job
any tip or help on this matter would be gratefull

david

Post by **paulk** » Tue Aug 22, 2006 3:15 pm

I used 1.2mm steel and found that plenty thick enough.

Post by **Stig** » Tue Aug 22, 2006 4:54 pm

Try to use a similar gauge to the existing panel. That way you're less likely to blow holes in one whilst trying to get good weld penetration in the other. Or at least blow holes in both equally!

Post by **nebogipfel** » Tue Aug 22, 2006 7:47 pm

I use 18g for general repairs.

Just about the thickest you can use and still cut by hand with a good stout pair of snips

John

Post by **les** » Tue Aug 22, 2006 10:15 pm

I also like 18g, not sure what that is in metric! Although I have only been able to find 1.2 or 1.6 in metric, the former being nearest. If you are welding metal of different thickness, I've found that starting the weld on the thickest first and then just sweeping onto the thinner enables you to make the weld.

Post by **Welung666** » Wed Aug 23, 2006 10:07 am

20SWG = 0.036" (0.91mm)
18SWG = 0.048" (1.22mm)
16SWG = 0.064" (1.63mm)
14SWG = 0.080" (2.03mm)

EDIT quick double check and recalc

Post by **chickenjohn** » Wed Aug 23, 2006 10:20 am

20 SWG is about 1mm isn't it? not 2.01mm. Welung typo? ;)

There are two schools of thought on fellow Moggie restorers I have spoken to about this- some like to use thicker steel than was there originally- presumably to make the car stronger, some like to try and match the cars original gauge of steel.

My friends in the local branch who are metal fabricators/ welders by trade like to use as close to original size metal as possible, so I'd go with that.

Personally, I use ~1mm for inner wings/ body panels, 1.2mm for chassis/ sills etc and ~2mm for inner sill repairs.

Post by **Welung666** » Wed Aug 23, 2006 10:44 am

Correct John

did that quickly from memory (shows what state my memory is in

) Dug out me Zeus book and corrected it anyway

Post by **chickenjohn** » Wed Aug 23, 2006 11:08 am

No worries, I just didn;t want the guy to order a 6'x3' sheet of the wrong gauge, imagine trying to form 2mm steel for body panels!

Ratbag · Post by **Ratbag** » Thu Aug 24, 2006 10:40 am

chickenjohn wrote:No worries, I just didn;t want the guy to order a 6'x3' sheet of the wrong gauge, imagine trying to form 2mm steel for body panels!

IIRC 2mm is ripe for arc (stick) welding... then any old paint becomes weld-through primer!