The Stovebolt Site Forums The Shop Area Paint and Body Shop Grinding Welds?

I am doing alot of patch panel work and the part I dislike the most is grinding down the welds after the patch is complete. It seems to take me a long time to get them ground down. What do you folks like to use to grind the welds down flush with the surounding metal? Thanks for any input.

I use a 3M weld grinding wheel in a die grinder, its like a cut-off wheel only thicker. Brian

I have found the thin grit disks work best at doing the final smoothing of the welds. The ones I use are 4 inches in dia and require a cardboard backing to give them some rigidity. Still a deft touch is needed to prevent heat build-up. The flap disks also work well but then to build up more heat.

cujo8,

My 5 cents...use a ridgid grinding wheel, not a
disc. If the grit of the wheel isn't coarse enough, you usually end up polishing/grinding and this is what takes the time. There is a wheel on the market called AVOS, which is an acronym for "Allows View of Surface". You can see the weld area as you grind it down. Stay with a coarse grit, 36 or 46.

If you grind the area down flush, then your weld needs to be 100% or you have NO weld left. The coarse wheels combined with the proper weld wire (MIG) make for a easy grind. The area being repaired will have primers and fillers applied to it, so a little rough might be better than smooth as glass. The coarse grits will remove metal faster and with less heat than a finer, fiber type disc.


Stuart.

I use 36 grit disks on my angle grinder. Have to be careful not to build up too much heat but they work fast.

I also use the grinding disks for common 4 1/2" grinders...but then I follow up with a cookie in my angle die grinder. Cookies are those scotch-brite type disks...you can buy them at most auto parts stores. They work very well and clean up the roughness from the grinder...

Try using a small roloc flap disc on an air angle die grinder.

Thanks for all the replies. Up til now I have been using a $35 Sears 4" small angle grinder and my die grinder with a 1/16" cut off wheel to grind down my welds and I felt it was taking way to long to grind them down. I just picked up a new DeWalt DW818 4-1/2" small angle grinder, that has twice the power and rpm's compared to the Sears grinder. This new grinder outfitted with the grinder disk it came with cut the welds down in no time, but I found I have to keep a close eye on my progress so I do not go too far. I did notice that alot more heat builds up when using this setup. I then put on a DeWalt 36 grit flap disk and I found this worked great and with less heat as well. I would say this new grinder setup is working 4-5 times faster than my old setup. I used to hate to weld anything on my truck knowing it was going to take me 5 times longer to grind the welds down.

Manuel, I have a roloc attachment for my die grinder, but I did not know they had flap discs available for them. I have never seen them anywhere before, where did you find them?

Burgie, I need to watch my weight, so I try not to keep any "cookies" in the house/garage.

I wish we were neighbors so I could do your grinding while you do my welding!

The most "fun" I've had was grinding down the spot welds to remove my 9-foot bed corner strips. They certainly intended to make it stick forever. I went through 4 grinder disks in the process.