What is the best way to grind MIG welds?

[wjc05sti]

I was just wondering what would be the best way/procedure to grind down MIG welds. Is there a type of product, machine that can do the job? Or do you just use a simple grinder to do so? How far do you grind the welds down?

[moody2.0]

whenever i mig weld i use a 4.5" angle grinder and a die grinder for those small spots

[Hotfoot]

My favorite way is a Flap Disc on a 4 1/2" angle grinder. Sometimes use a grinder, but seldom, the flappers do such a good job,, and leave a nicer finish.

[koreanbeefcake]

My favorite way is a Flap Disc on a 4 1/2" angle grinder. Sometimes use a grinder, but seldom, the flappers do such a good job,, and leave a nicer finish.

why not just grind it, and then use like 2 passes of the flap? wouldnt that save time?

[Hotfoot]

My 40 grit flaps do a faster, nicer job than the grinder. I reserve the grinder for "heavy" removal, and occasional bird poop gobs that mysteriously appear on my work!

[hankj]

wjc05sti,

Depends.

I prefer not to grind a weld if it is not necessary. If the weld has to be blended, I like flap disks like George. For heavy removal, a 36-grit disk on the 4.5 or 7 inch grinder. For welds that need to be dressed for appearance, but are in places where you can't get a disk on them, I like die grinders.

If there's no appearance or clearance issue, I think a well done weld is pretty enough to be flaunted! I just leave 'em alone if there's no issue!

Hank

[Sandy]

I use a grinding disc for heavy removal, flap for smoother finish or where you gouging might be an issue.

I have problems with the coarse flap discs flinging their grit before all the flap is flapped so I don't keep many around. Mostly fine as in 80 grit or so. Probably operator error.

[Farthur]

on those occasions when a flat surface is required, (such as the inside of a precast cement form), I use a hard disc first to rough down the weld 'till it's almost flat, and then finish it off with a 60 grit flap disc.If the perfectly flat finish wasn't required though, I'd pass on the hard stone every time. The 40 grit flap disc can 'oinc' it down faster than the hard stone and I have more important things to use my time on - like laying down more welds.