Stone & Iron/Nickel Spheres

[rgarner]

Hey all, first time poster here! Looking for a bit of knowhow.

I work with meteorites. Some are stone, others are iron/nickel (90/10 split). Essentially I want to make meteorite spheres for jewellery (beads, pendants, etc), but it needs to be an automatic process. Making them by hand, even with the right expertise, can be very difficult and time consuming from my limited understanding - plus there is a lot of waste if it goes wrong and meteorites are not cheap!

I am based in the UK, so my market is pretty limited already. Does anyone know of a bead making machine that can use stand alone pieces (i.e. not cut from a long block, etc.)? Or any other method of making spheres?

I would greatly appreciate any advice!

Thanks,
Richard

[ileney]

Modified- Oops. Just came upon the thread about spinning beads and read that even preparing a stone for a bead mill is time consuming or I would not have suggested that. I had seem used Covington and other bead mills for sale from time to time on ebay but have never seen them used, so did not know what was involved. I somehow had visualized just loading any old stone in and presto getting a bead out the other end. LOL.

[slabbercabber]

Ball bearings are made by putting the raw material between two plates with abrasive and rotating one.  Shouldn't be too hard to make such a thing.

[rgarner]

Covington have two machines could possibly be used, one is the tiny bead machine (which produced one ball slowly over time - not ideal) and the other is a grinder, but the balls are not perfect spheres, nor are they uniform. Plus they're not sold in the UK.

My plan thus far is to use a lapidary drill with a spherical grinding bit, and have another identical bit locked in beneath - though I have had to order these from the US and they won't arrive for a good two weeks. I'm not sure this method will even work, which is why I posted here.

I'm not an expert when it comes to these kinds of tools and I've spent a good $2000+ over the past year on various tools, some of which just did not work for what I wanted them for. I'd rather not spend this kind of money without first knowing if it will work - to give you an idea, the small bead machine costs around $450 and shipping to the UK would cost $300...

[bobby1]

Diamond hollow drill bits won't work on metal like the iron/nickel meteorites. The will work on the stone ones, though.
Bob

[rgarner]

Thanks Bob. What kind of bit would work on iron/nickel?

[bobby1]

I have used a copper pipe that I can mount in a drill press. Cut notches in the working end of the pipe with a hack saw. Mount the piece of meteorite in something to hold it steady and so that you can wet it down. I use masking tape to enclose it and so I can hold some water and tumbling grit at the contact with the slotted end of the pipe. Move the copper bit up and down slightly as you drill. The slots in the copper pipe will capture the grit and due to the softness of the copper some of the grit will embed itself into it and cause the grinding action.
Diamond core bits tend to struggle with drilling the metal because the metal tends to attach itself to the bit and cover the diamonds so they become less effective.
Bob