Best Way to Remove Mill Scale?

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I want to remove the mill scale from the 2" pipe I made a table stand out of before painting. What is the best way to do it? I am familiar with the wire cup on the grinder (too familiar) Just wondered if there wasa chemical way to remove the baked on oil.
Reply:Acetone.  That's what I use but usually after I've buffed with a wire wheel.  Should work for the oil anyway.Wanna-be welder formerly known as Bender
Reply:I don't think you're talking about mill scale, if it's black iron pipe, that is varnish on the outside.The best thing is to sand the varnish and paint.Appreciation Gains You Recognition-
Reply:Its not iron, its steel sched 40 pipe. The black stuff comes off but with difficulty. Acetone doesn't really do much to it except get the rag black. I know I can grind it off  but I was hoping there would be a way to soak it off. Looks like old fashion elbow grease is the best answer!
Reply:Tubeman,I use a solution of 9 parts of water and 1 part of muriatic acid. Immerse the parts oin that solution and after 10 to 15 minutes the scale is very loose so it is very easy to sand off. It has worked perfect for me, but I use small pieces. It can be cumbersome to work with big parts unless you devote a tank just for that
Reply:The acid bath works fine if you can get it in the tank.  Otherwise, sand blasting will work well.Get it hot and hit it hard...
Reply:I sandblast or grind.  ASME and Military specs usually call for grind or sandblast within 1" of the weld.  That's inside and out, providing it's a full penetration weld.Proud to be a UNION worker.  Better pay, better benefits, better work environment.  UA Unions = working for the working class!!
Reply:I just finished doing about 20' of pipe.  I tried two methods.  I used a hand held torch,baked it then brushed it off with a hand held brush.  I also did some using a heavy duty grinder with a 4" wire brush attached.  Both methods were time counsuming.  With both methods I used laquer thinner to wipe the stuff off.  I was hoping to find a better method.  I also did some minor sanding before priming the metal.