What is the "best" thing to use for grinding welds?

I used to use the stone that came with my 4 1/2" angle grinder. It was very loud and didn't do much.

Then I found the flap-discs that look like pleated sandpaper with a backing and they grind quite a bit quicker than the stone does, and are much quieter, but they don't last all that long.

Am I using the best thing, or should I go get something different that would work better? If it matters, my welds are all flux-core wire-feed.

Thanks, y'all.

What i use is called or under the 3M name of ROLEC discs. They come in sereval diff sizes and grits. The size I use is 3in. What it is a flexible hard piece of sandpaper that screws into an attachment that can go on die grinder or drill. You can get them at any body shop supply house, all body shops I know of use them. In my MAC tools catalog they are called 3M rolec green corps sanding discs. I use them just on small welds but mainly to smooth them out.

I use a cutoff wheel with a 1/8 wheel to hog down the weld bead, then come back with those rolec disc to smooth them out...Eric

An air powered die grinder works best, with either two inch or three inch sanding discs.

I've used the 1/8 cut-off wheel and also carbide burrs (the kind you use to port cast iron cylinder heads and clearance blocks). Both work great.

The burr does not throw sparks, but it does fling chips off pretty good. Wear safety glasses, long sleeves and maybe some hearing protection (especially with air tools; spend 4 hours clearancing a block and you'll know what I mean) with either application.

When using the cut-off wheel, try to wear a dust mask; otherwise you'll be blowing black boogers out of your nose for a while. :D

Crankshaft

Personally, I stick with my 4-1/2" grinder. It sounds like your wheel may be too hard. Ideally, you want a hard wheel for soft metal (lasts long) and a softer composition for a hard metal (keeps exposing new sharp grit)

Don't have info with me, but there should be a code on most grinding wheels. Talk to a welding shop, may be they can tell you how hard/soft your is and/or recommend a good wheel for weld grinding. The proper wheel should just blaze through the metal...be careful not to get it too hot and warp it.

I've used a Roto-Zip I bought at sears.I use the 36 grit disc's they have for it.It works fast and pretty quiey.Plus you have the option of different speeds.

sounds like some pretty nasty welds, are you doing frame repair?

I have a pistol grip sander that works great. You can get an assorrtment or grit discs like what sevt_chevelle is talking about.

I use the roloc discs on my angle die grinder. Work great on welds. Buy the 50 grit green ones. Cheaper than 40 grit and work nice. For heavy beads I sometimes use the flap disc you describe on my 4 inch electric grinder, but I agree they don't last too long. Try the angle grinder and some roloc discs, you will love them.