Need some #500 Carborum grit

Discussion in 'Medium Format Cameras and Accessories' started by Gustavo_Castilla, Nov 11, 2005.

  1. Gustavo_Castilla

    Gustavo_Castilla Member

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    Hi I need to work on my groung glass and I do not know where to find the #500 Carborum grit
    Thanks Gustavo@gcastilla.com
     
  2. BOSS565

    BOSS565 Member

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    You might try MSC Industrial Supply in NY. Their web address is www.mscdirect.com
     
  3. Mateo

    Mateo Subscriber

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    You can also try Daniel Smith or Dick Blick art supply
     
  4. Dave Parker

    Dave Parker Inactive

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    As I posted to your classified ad, your best place to try is your local rock/hobby shop as this material is used in the tumbling of rocks and stuff.

    Dave
     
  5. Donald Qualls

    Donald Qualls Member

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    Depending how much you need, you might also try http://www.gotgrit.com/ -- they sell primarily to telescope makers for optical grinding, so the quantities might be a bit large, but they're certain to have what you want. If you're making a ground glass, you could probably finish the whole job with a 35 mm film can full (I used less than that in this size for an 8" telescope mirror, though the surface was ground to 320 before I started with the 500). The lapidary shops will almost certainly sell in a minimum of a half pound, too, so take your pick...
     
  6. paul ron

    paul ron Member

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    Wet dry saning paper.

    You can get some wet/dry slicone carbide sanding paper in 400 or 600 grit. It's used for polishing wood n metal, will cut glass just as easily. Home Depot has it, it a dark gray color.

    If you can't find any, e-mail me, I'll send you a sheet.
     
  7. Ole

    Ole Moderator Staff Member Moderator

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    Just a little hint if you try a Google search: It's carborundum. :wink:
     
  8. Donald Qualls

    Donald Qualls Member

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    Also known as silicon carbide, BTW; Carborundum is a brand name.
     
  9. MattCarey

    MattCarey Member

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    Interesting--I kept thinking in my mind "corundum", which is the structure of sapphire.

    I would bet that the guys who trademarked "Carborundum" had the similarity in mind.

    Matt
     
  10. Struan Gray

    Struan Gray Member

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    You can also get the grit from Car DIY and workshop stores: it's sold as valve-grinding paste for lapping the valves and valve seats when you've run your old engine on lead-free petrol a bit too long.....
     
  11. Donald Qualls

    Donald Qualls Member

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    That was exactly the intent -- it was marketed originally as a synthetic subsitute for aluminum oxide, which is corundum. It's similar in hardness and cuts faster because the more jagged grains spall out chunks of the work as they roll during (optical) grinding, or cut larger chips for a given grit size in applications like grinding wheels and sandpaper.
     
  12. Phillip P. Dimor

    Phillip P. Dimor Member

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    http://www.kingsleynorth.com/

    I've ordered from this place, they are GREAT. Had it in about 2 days.
    Cheap. They also have silicon carbide and aluminum oxide. In MANY grades.
    Many types of grinding and polishing compounds. Cool stuff, my father used to make jewelry and he seemed to like the catalog too.

    Locally I was able to get a medium grit valve grinding paste. Too rough but good to start out with. If you start with a coarse grit and finish with a fine grit I think it makes a large difference.

    PS- I forget what size grit I used for my ground glass but man, I was happy with what I was able to make for my 4x5. BRIGHT! And I made about 2 dozen pieces in two hours. Use a wetstone for grinding down the edges of the glass as well.