This is something that seems to be lacking on the web. Not just tutorials in general about cabbing, but how to cab the itty bitty stuff. So I thought I'd put this together real quick and attempt to convey what I know about making little stones like 3.5mm opals.
A few things to note and have:
First, I'm not sure how to get the images in line for the instructions, so I've hosted them on my personal website for now so I can intersperse them through the tutorial. I hope they show up okay for everyone.
Second: things to have: You will need the following (beyond the obvious such as a machine or system for cutting stone):
-Toothpicks that have a flat head on one end (if you have a fine fine sawblade you can make your own as well, but try not to make them too short)
-Shelac sticks. Can be purchased online (I get mine from
Arrowhead Lapidary-Denatured Alcohol
-Glass container with lid that is big enough for a Q-tip to fit in with the lid secured on. For this tutorial, I'm using an old spice container.
-Dop Wax (of course)
-the rock you wish to cut.
-faceted alcohol lamp, or other method for heating dop wax on stick
First, cut off a piece of the shelac (about 1/4" or so will do), and put it in the glass container. Then pour in denatured alcohol so it is about 6parts in volume more than the shelac at least. You can see in the following picture how much liquid I have in the glass container, and what it looks like after the shelac has disolved neatly into the alcohol:
Next, the toothpick:
However you choose to get the wax onto the stick, get a decent glob on there. I just stuck mine in the dop pot for a quick dip and then pulled it out:
Your stone can be cut down pretty small by hand if you use a grit of around 220 that you aren't afriad to get your fingers to close to. If your target is a round stone, square off the rock and then take off the corners to make a rough octogon
The following is the stick next to the rock
IMPORTANT: get the stone warm. Set it on a surface to warm it up, and while waiting, take the q-tip and dob a little of the shelac liquid on the stone back (the side you want the wax to stick to). Depending on how thick/thin the solution is, you may need to do it more than once, but if you aren't sure if it's enough, you can coat it while holding the stone, and blow on it and see the alcohol evaporate, then recoat, *then* put it on the heat source. My little glass jar tends to lose alcohol over time because it doesn't have a perfect seal, so I have to add some now and then. Right now it's about perfect.
While the stone is heating up, heat the wax on your toothpick dopstick until it's just about dripping off (rotate the stick in order to keep this from happening, lift the stick further away from the flame to cool it off, etc. Same as full size dopping.
Next, when the wax is hot, carefully, vertically, apply the dop stick to the stone. This may not always be perfectly straight, as you have a small target.
This is where it can get painful. Lick your fingers if you wish, but you need to get the stone centered, and the best way to do that is to quickly grab the stone and the wax and moosh them into place. The wax is hot, so it'll likely hurt a little. If you lick your fingers it *should* keep the wax from sticking to your skin. If the wax *does* stick to your skin, utter appropriate fowl language while quickly looking for a cold water source.
ANOTHER important note! Make sure your locations of your alcohol lamp, and stone warming unit (I use a dop pot) are not in precarious positions where you might burn yourself as you quickly move the dop stick to stick it to the stone (yes, I've singed my arm).
After pushing it around and burning your fingers, the stone should be level and roughly centered on the dop stick as so:
Let the whole thing cool down by air, don't quench it (if you do this, I'm not sure how it will affect the shelac, but I *do* know it'll crack an opal.
Once all is cool, you can turn your machine on and apply light pressure to the wheel while briskly rotating the stone against it back and forth by twirling the tooth pick. I have a special tool that I use to keep it straight on the wheel, but won't go into that unless someone wants it. I assume we all have our methods.
The quick rotation works to round the stone off. This works on odd shaped stones as well, so long as you grind off any primary spots where it is sticking out or angular.
This is the stone in the example after about 30 seconds to a minute of twirling on the 220grit on my Genie. The stone is currently just over 5mm in diameter.
I hope this will help some people out. I know there are guys/gals in Korea and China that do this sort of thing day in and day out (and get paid dirt for it), and their work makes mine look childish, but you have to start somewhere.
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