Belt Sanders

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First post, love the site.Our company makes a lot of tank welds, and by the time the guys get done using a sanding disc with a side grinder around the welds, its looks rather crappy. We thought a belt sander would keep it clean. Without much research, could someone recomend me one? Link would be great!ThanksDave
Reply:Why don't they just hire a welder that can lay down a good looking bead and not have to grind anything?
Reply:Yeah, I hear that.But to clarify, it's more for cosmetics. As in, when you see tanks and vessels from 'other' shops, they tend to have a nice uniformed polish around the welds. As in, the weld itself and a couple inches on both sides; uniformend. I assume a belt sander with a fine belt would work, or perhaps it's done on some machine, excuse my ignorance.
Reply:I tend to to do a very high level cosmetic finish on just about everything I do. And I find that to grind out welds, you need several steps.On big welds, lumpy mig beads or fat stick, I use a grinding wheel on a 4 1/2" grinder first. On tig welds, we go straight to step 2- a flap disc mounted on a 4 1/2" grinder, I really like the 50 grit alumina zirconia from Klingspoor- they are very agressive, and will really cut thru weldbead, but leave a very fine finish.Then, after its flat and pretty free of big scratches, you might hit it with a belt sander.The brand of sander is not too critical- I prefer Bosch for most of my hand power tools, with a few Milwaukees- but I think the Milwaukee belt sanders, like my 4x24, are awfully heavy for throwing around all day.Again, I use blue alumina zirconia belts from klingspor- what they call CS411. That stuff lasts forever, and really cuts. Unlike brown woodworking sanding belts, which will last about 30 seconds.Grinding a weld out seems like grunt work, but to make it look good it usually means the highest paid guy in the shop has to do it. It takes a lot of attention to detail. In my shop, that means me, the boss, often does the final pass.There are some really cool giant belt sanders that hold the belt in the air between two rollers, which they use for polishing stainless steel pipe joints- and one of them would work for what you want- it gives a food quality finish- not cheap, you generally suspend them from the ceiling- Fein, which makes some of the best power tools in the world (think mercedes, and mercedes prices) makes some kinda like this-http://www.feinus.com/p/stainless/stainlessmain.htmthese guys also make some cool sanders and grinders-http://www.csunitec.com/sand/sandgrind.html
Reply:Ries,Thanks for the CS Unitec link. That's something I could use.Aloha,oldebrush
Reply:We do a lot of stainless work and everything from removing the weld discoloration only to mirror finishing.  Because we do a lot of work for the food and pharmacuetical industries all the welds have to be ground flush with the base material, pit and crevice free, and then polished to a minimum of 180grit.  We buy all of our polishing tools from the two companies that are really the leaders in this area (Dynabrade www.dynabrade.com) and (Suhner www.suhner.com).  The tools are expensive, but, if you use them all day long like we do they pay for themselves as they do not break down and get the job done quickly.  For stainless work we grind the welds flush with an 80 grit flap disc (www.lehighvalleyabrasives.com) and then generally switch to a medium scotch brite belt for providing a satin like finish.  Depending on the weld and location will determine the tool we use for belt polishing.