Best way to remove mill scale?

Discussion in 'Shop - Fabrication' started by stnkbg1, Dec 4, 2008.

  1. stnkbg1

    stnkbg1 New Member

    Joined:
    Nov 14, 2007
    Location:
    San Diego, CA
    Now that I've got my Torchmate plasma table up and running I've obviously been going through a lot of flat plate. I've also been practicing a lot with the TIG, and to get good welds you have to take that black coating off of the plate first. I've always loved my 36 grit sanding disks for shaping and smoothing parts, and they work great to remove the scale when they are new, but they quickly get polished smooth and stop working. My wire wheel doesn't do any better. What are you guys using to get your steel clean?

    Thanks.
  2. JEFFRPM

    JEFFRPM Non Sugar Coated

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    Jan 7, 2008
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    Under the Tetons
    glass bead blaster
  3. ErikShallbetter

    ErikShallbetter Active Member

    Joined:
    Oct 31, 2005
    Location:
    Minnesota
    I believe you are getting a " hot rolled " condition plate. Next time you order plate buy "hot rolled pickeled and oiled" (HRPO) and it should not have the black scale that is giving you problems.
  4. f1sleepy

    f1sleepy Active Member

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    Jun 25, 2008
    Location:
    Escondido, CA
  5. stnkbg1

    stnkbg1 New Member

    Joined:
    Nov 14, 2007
    Location:
    San Diego, CA

    Yes, that's exactly the issue. The problem is that none of the suppliers around here seem to carry HRPO or Cold Rolled, and I dont have the $$$ to order the amount they require for a special order.

    I'm certainly willing to give those stripping discs a try. Would my Local welding supplier have them or are they something I'll need to order?
  6. f1sleepy

    f1sleepy Active Member

    Joined:
    Jun 25, 2008
    Location:
    Escondido, CA
    Honestly, for the price I would just order them direct from the link I gave you. Even after shipping they are cheaper than buying them from a shop/hardware store and they will be at your door in 2-3 days tops. They work really well and seem to last pretty long too.

    James
  7. ErikShallbetter

    ErikShallbetter Active Member

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    Oct 31, 2005
    Location:
    Minnesota
  8. tmathews

    tmathews Well-Known Member

    Joined:
    Feb 2, 2005
    Location:
    Alpine, Ca
    Hey Dallas.... I can order you some those Non Woven Discs... www.unitedabrasives.com.
    The mfg makes a non woven stripping disc in a 4-1/2" diameter.

    A little pricey @ $15.60 ea.
  9. Racer Tim

    Racer Tim Member

    Joined:
    Aug 21, 2007
    Location:
    Ca
    Try and find someone with a time saver(big belt sander for cleaning metal in sheet form), sheet metal shops use them quite a bit for doing just that and there alot fast than a sanding disc.
  10. ErikShallbetter

    ErikShallbetter Active Member

    Joined:
    Oct 31, 2005
    Location:
    Minnesota
    We have a timesaver in our shop but that mill scale is nasty. The idea is good, (we even tried it more than once with different belts) but we have not had good results in the past removing mill scale with the timesaver.
  11. dirtdudeaz

    dirtdudeaz Member

    Joined:
    Jun 19, 2007
    Location:
    phoenix, az
    timesavers are nice and everything, but mill scale over and over would tear those belts apart in no time. And as expensive as they are.....

    why not invest in a standing belt sander such as a burr king
  12. dezertrat82

    dezertrat82 Member

    Joined:
    May 18, 2006
    Location:
    Santee CA
    How thick of plate do you need? I know that competitive metals in el cajon 619-442-4130 sell cold roll. just bought a 4x8 sheet of 1/8 for i think $156 could be wrong though.
  13. f1sleepy

    f1sleepy Active Member

    Joined:
    Jun 25, 2008
    Location:
    Escondido, CA
    The discs I posted a link to cost a quarter of that.

    To the OP:

    Trying to clean an entire sheet will be a little tedious but the discs work very well for very little money. I'm guessing you are trying to find 3/16" inch plate since you can't find it in cold rolled. I am surprised you can't get HRPO. I know Summit Steel in Oceanside carries it and they will deliver. It's another option to consider. IMS should carry it but I don't deal with them.

    James
  14. HardCharger81

    HardCharger81 Member

    Joined:
    Mar 3, 2006
    Location:
    Elk Grove, CA
    A one time we were using a "soap" I guess you could call it, and it would eat up/loosen mill scale, oil, rust, etc...

    Basically, using heavy rubber gloves, you'd bathe the steel in this soap, and it would strip/etch it.
    I'd have to ask my dad what the exact name and where to get it.
  15. Brian Mapes

    Brian Mapes Member

    Joined:
    Dec 13, 2002
    Location:
    Corona, Ca.
    You need to go to your nearest welding supply and pick up some Norton rapid finish or rapid strip pads. They come with a 5/8 -11 arbor or 7/8 hole and they have them in a few different grits.. i use them for removing mill scale before Tig welding and they work great. I also sell them and have heard nothing but compliments from people i sell them to. The black color one is a course and the tan color is fine which polishes out pretty well. I am in corona and carry them if your ever down this way.
  16. stnkbg1

    stnkbg1 New Member

    Joined:
    Nov 14, 2007
    Location:
    San Diego, CA
    I'll try calling Summit and IMS and ask about the P&O. That would be a way better option than any stripping method. Heck I'm down in East County enough that Competitive is an option as well. Thanks for the tips.
  17. loufish

    loufish Member

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    May 7, 2005
    Location:
    Burbank, CA
    I use a 4-1/2" angle grinder with a flapper wheel...but I'm just cleaning up the weld area, not the whole sheet...

    I avoid HR at all cost if possible, but some times you need some thing that will form better with out cracking....

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