Polymer clay bead rollers seem a bit expensive to me. Plus they only make them in one size and a set of shapes. So I thought I could make a quick and simple one for cheap! First off I should make the disclaimer that "I made it at TechShop", so I had a lot of great tools at my disposal. One of the other members in the shop had some clay that he used for a project that had gotten plaster and dirt in it so he was going to throw it out, so I rescued it to make slingshot ammo out of. I'll be writing an instructable on making a slingshot soon!
The basic concept is you have a cylinder sawed in half lengthwise to give you two half cylinders. You put a measured amount of your medium (clay or polymer clay) into the center, rub the two halves together and you get a perfect sphere.
Now you can use these for making polymer clay beads for your jewelry project. You can use these to make perfect little spheres of fish bait, the English call these "Boilies". We in the States just call them dough bait balls. I also used this to make perfect ammo for my slingshot out of clay. It's biodegradable and non-toxic.
I should also mention that I have plans for other ways of making bead/ball rollers so I will be adding to this instructable in the future. One of the issues with this method is that it only does one ball at a time. I want to make a tray so that I can roll multiple balls/beads at once! And I'm working on ways to do just that.
1/2" PVC pipe, you only need a 2-3 foot length of this. This makes beads/balls about 15mm in diameter. You can experiment with other sizes.
Saw, I used a band saw with a thin blade
Sandpaper, I used a belt/disc sander
Clay or Polymer Clay
Step 1: A Word About Kerf, and a Little Bit of Strategy.
Kerf is a word I'm going to use, and many people may not be familiar with the concept. Basically it's the amount of material removed by the tool you are using to cut with. We could just cut our PVC pipe and use the two halves, but then we would end up with a more oval shape because the two halves wouldn't be perfectly semi-spherical. So the most important part of this project is that we want to adjust for the kerf. My solution is to cut just shy of center and throw one piece (the smaller piece) away.
Actually I cut just shy of the center line of the tube, and then sanded the good half down on the belt sander to get a somewhat perfect semi-sphere. This also gets rid of some of the bits and pieces that stick around after cutting.
Now the other important issue is that we want a straight cut. We don't want the tube to rotate at all while we are cutting it. So to alleviate this issue, I glued the pvc tube to a spare piece of wood. I used Gorilla glue because it foams up and makes more contact with the round PVC tube. I let this dry overnight and picked the project back up the next day.
Step 2: Make a Jig and Cut the Tube
I clamped a scrap piece of wood to the band saw as a guide so that I could get an almost perfect straight cut. I didn't bother to measure and mark the perfect center line of the tube, I just eyeballed it. Basically I want to have a smidge more than half on the right side of the picture.
Once the tube has been cut, I threw out the waste piece glued to the wood. Then I just cut my good perfect semi-spherical half in half so that I have two pieces instead of one.
Step 3: Roll Your Balls!
The basic technique that I use is to roll out my medium in a snake like shape until it's about the same width as the inside of our nifty new bead/ball roller. Then I pinch of what looks like the appropriate amount and place it in the bead/ball roller. Then rub the two halves together to form the ball. If you have too much you'll get a weird shape, so just pinch some material off and re-roll. If you don't have enough you'll be able to tell as well, so just add a pinch of material and re-roll.
I used this ball/bead roller to make a bunch of clay ammo for my slingshot (Instructable on how to make that coming soon). I just baked the clay (after drying for a day) in an oven at 450°F (230°C) for an hour. You don't need a kiln, we want these puppies to explode in a poof of clay dust, they just need to hold up long enough for use to shoot them.
I also made some slingshot ammo/balls out of Polymer clay. This just bakes in a toaster oven at 275°F (130°C) for 20-30 minutes. Some polymer clay is different and you should follow the cooking time and temperature on the package. You should also never use a toaster oven that you used for polymer clay for food. Keep it for projects only. They are cheap anyway. I just popped mine in the powder coating oven at the shop.