Cleaning Mill Scale

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I'm at the point where I'd like to clean the mill scale off the top of the table.So far I haven't found a process which leaves a finish I like.I've tried using a 6" random orbit sander. It hardly touched it with 60 grit.My belt sander can't get the job done either.I've tried a 4" flap disc which cleans it but I don't like the finish.I'm at the point where I'm thinking of just leaving it on the steel, but I'm not thrilled with it.Is there something short of having it milled that will leave a nice finish?Thanks for you help.
Reply:A tight bead wire wheel will take it off, but it will be time consuming and labor intensive. There's not too many good ways to do it. The chemical route comes with its own challenges too. Machining the pieces can prove to be tricky. You'll need to get them really flat, and with a small mill will take awhile.Wish I had a better answer.Expert Garage Hack....https://www.facebook.com/steven.webber.948
Reply:Needle scaler would take it off. Still going to be a little slow. Or....  you could possibly make it rust which might break it's bond with the steel and then clean it all off.
Reply:Leave it on & grind it off when welding BB's stick.  Eventually it will be all gone.MarkI haven't always been a nurse........Craftsman 12"x36" LatheEnco G-30B MillHobart Handler 175Lincoln WeldandPower 225 AC/DC G-7 CV/CCAdd a Foot Pedal to a Harbor Freight Chicago Electric 165A DC TIG PapaLion's Gate Build
Reply:If it's not too hard to move, you might want to get it sand-blasted.GraysOrnamentalIron.com
Reply:I use a 3M paint removal wheel. There are other makers that offer the same thing but I do not know the brands. It is the fastest thing I have seeen to remove the mill scale.  The scale has a lot of carbon in it so it is hard and most abrasives either get dull fast or are too aggressive and remove metal under the scale. This is what they look like http://cgi.ebay.com/ebaymotors/3M-31...4AAOSwq7JT4ndi  They make them in different sizes and with madrels already in them. I use a 4" x 1" with a 1/4" shank in an air die grinder. Make sure you use a face shield because the scale flys off in chucks some times. They are also made for a 4.5" grinder but they wear out faster so I use the wheels in a grinder. Do not force it or you will wear the wheel out faster just let it work at its own pace and keep it moving. I would guess it will take 15 -20 minutes to clean the scale off your table top with one. Why didn't you use cold rolled for your table top? It would be much flatter and 20% stronger and it would not have any mill scale on it.Last edited by thegary; 03-16-2016 at 10:48 AM.
Reply:When I hold a 4 1/2" grinder with a sanding disk and backing pad perfectly flat and run it around on the surface, it takes any spatter and loose junk off without hardly scratching base metal, even with a 36 git disc. Of course the arbor can't protrude and keep it from riding flat. Don't tilt the grinder or it will dig in.  I have the same build pro type table, I'm not sure why any mill scale would be a problem, I love it, except the price. My main goal would be to keep it perfectly flat.
Reply:Originally Posted by thegaryI use a 3M paint removal wheel. There are other makers that offer the same thing but I do not know the brands. It is the fastest thing I have seeen to remove the mill scale.  The scale has a lot of carbon in it so it is hard and most abrasives either get dull fast or are too aggressive and remove metal under the scale. This is what they look like http://cgi.ebay.com/ebaymotors/3M-31...4AAOSwq7JT4ndi  They make them in different sizes and with madrels already in them. I use a 3" x 1" with a 1/4" shank in an air die grinder. Make sure you use a face shield because the scale flys off in chucks some times. They are also made for a 4.5" grinder but they wear out faster so I use the wheels in a grinder. Do not force it or you will wear the wheel out faster just let it work at its own pace and keep it moving. I would guess it will take 15 -20 minutes to clean the scale off your table top with one. Why didn't you use cold rolled for your table top? It would be much flatter and 20% stronger and it would not have any mill scale on it.
Reply:Scotch brite pads work good and don't dig into the metalI use them on buffing handrail and the like.
Reply:SmasonOn a table - mill scale is your friend - wheels are your enemy.Opus
Reply:Originally Posted by OPUS FERROSmasonOn a table - mill scale is your friend - wheels are your enemy.Opus
Reply:slats look to be removeable, soak them in vinegar i use a 30% concentrated.     or a diluted muriatic acid
Reply:On a welding table, I'd just leave the mill scale on.  The mill scale helps prevent rust, as it's already another form of iron oxide.  If you clean it down to shiny metal, it'll want to flash rust all the time.  Of course a little WD-40 or light oil wiped on with a rag solves that problem.The lowest PITA way I've found to get rid of mill scale is to leave the metal outside and let the mill scale convert to rust.  Then it's way easier to grind/sand/sandblast.  The mill scale is a pain since it's well bonded to the metal.Leaving it outside to rust isn't a great solution.  It takes some time.  For small parts it's probably not worth it.  For large parts the time saved in sandblasting is worthwhile.Dynasty200DX w/coolmate1MM210MM VintageESAB miniarc161ltsLincoln AC225Victor O/A, Smith AW1ACutmaster 81IR 2475N7.5FPRage3Jancy USA1019" SBAEAD-200LE
Reply:Smason,It's been my experience that having a heavy layer of tightly bonded mill scale on a table top is more often than not a good thing.   If that were my table and I was going to be using it mostly for the precision fabrication of stuff using short circuit mig I'd be leaving the mill scale on it.  That mill scale is like having a non-stick surface for light to medium spatter.  Most of the time all it will take to remove it is a light scraping with a chisel where as if you remove the mill scale you'll more often than not have to be using a grinder to get it off so it doesn't interfere with your fit up when you go to reset and re-clamp things.That's such a sweet looking table as it sits that I'd hate to see you end up regretting having taken the mill scale off of it.
Reply:With the mill scale left on your table top one of these masonary chisels that's had the end ground off square (just like you'd sharpen a putty knife or gasket scraper) will easily remove 95%+ of any spatter that gets on it with just a light scrap at it.
Reply:Ok thanks for the advice. I'll leave the mill scale on it.
Reply:Originally Posted by tracymobilecncslats look to be removeable, soak them in vinegar i use a 30% concentrated.     or a diluted muriatic acid