No announcement yet.

Scratches on PMC

  • Filter
  • Time
  • Show
Clear All
new posts

  • Scratches on PMC

    Hi there, I wonder if anyone can help. I've made about 100 PMC fingerprint charms for Christmas orders and haven't been doing it for very long. My pieces turn out beautifully, however, most of them have light scratches all over them even after vigorous polishing. Whatever I try I just can't get of them! It seems to be happening at the dry clay stage when I sand them down. I use sanding pads around the edges and over the surfaces (bar the fingerprint and engraving) - I think this is what's causing it because I can see the scratches on the surface after I've sanded.

    Its definitely not my burnisher. The only other thing it could possibly be is either the soft brass brush which I use on the piece after firing, or its happening in the polishing process (I use the graded polishing papers) but I can't see it somehow.

    What should I be using to sand the dry PMC? Has anyone else experienced this?

  • #2
    Fine silver is soft so it will scratch easily, and a brass brush will put light scratches in.
    when you work through the grades of paper try to work in a different direction to the previous grade, this way you remove the scratches. If you work in the same direction you just mask the scratches and they then show up in your final polish.
    [email protected]
    Facebook group


    • #3
      Sounds like you're using all the right things, the polishing papers are very good and will help get a good polish, as will the burnisher, just make sure you work through all the grades...

      Kernowcraft Rocks & Gems Ltd
      Your Destination For Gemstones & Jewellery Making - Since 1967

      For jewellery making advice, call our friendly team on 01872 573888



      • #4
        If it is anything like wood, working through the grades as mentioned is really important. It's easy to get impatient and jump one but if you do, the small scratches will remain and show up when polishing.

        "Where the spirit does not work with the hand, there is no art" ... Leonardo Da Vinci



        • #5
          I would echo Karens comment about how fine silver will scratch so much easier than sterling. Cut out the brass brush and it should be fine.

          silver jewellery at The Silver Jewellery Workshop
          bespoke handmade jewellery
          Silver Jewellery blog
          Handmade Jewellery Blog


          • #6
            Im not sure if this will help, as I have only been researching PMC (going to treat myself to a kit after Xmas) and I saw on a video somewhere, that if you are going to use grading papers, you should lay the paper on a table with some soft cloth underneath and then rub the pmc piece in a figure of 8 over it. this means that it gets all the marks from each direction and the cloth underneath means the polishing surface is soft enough to envelope the piece so that the edges also get polished.

            Hope that helps.


            • #7
              Originally posted by silverjewelleryworkshop View Post
              I would echo Karens comment about how fine silver will scratch so much easier than sterling. Cut out the brass brush and it should be fine.

              Thanks for all of your answers, Caroline, what would I use in place of a brass brush to bring out the silver? I can't really avoid using the brush because I need to get right into the print.


              • #8
                Jools from my limited experince with fingerprints (i've only done them for me)
                I don't think you can avoid using a brass brush.
                Try using the brush in one directions rather than in a circular motion.
                then when you move to your first grade of paper work at 90 degrees to this, any deep scratches will be visable and you can keep working in this direction until they have gone. if you carry on like this through the grades of paper you should achieve a really good finish scratch free!
                [email protected]
                Facebook group


                • #9
                  This might be a daft question but are you using lubricant with your brash brush.
                  Using it under running water and adding fairy liquid might help
                  **FREE to enter monthly draw on my BLOGS**
                  Different prize every month
                  Jewellery Creations & Shop Blog
                  PMC & Silver Clay Hints and Tips Blog