Grooved Cabochon Insert - Directions

Think Safety:

Be proactive about safety. Take classes, do research, and talk with experts. Actively work to identify, and then reduce or eliminate hazards. You are responsible for your own safety and long term health.
Always use the correct filtered glasses to protect your eyes.
Wear appropriate clothing and footwear.
Always work with proper ventilation. Talk with an expert about your situation.
Set up and operate your torch system safely. Take a class or get an expert to show you.
Keep your workspace clean and organized. Set up your tools and glass so you don't need to reach over or around the torch.
Be careful with water. Putting hot tools or glass in water can generate steam. Long tubes can create jets of steam.
Watch out for repetitive strain injury (RSI). Take breaks, watch your posture, and cushion your elbow rests.
Always remove and clean your beads while wet to minimize bead release dust in the air.

Multi Mandrel Safety

DO NOT USE FOR BLOWING. This mandrel is not designed for blowing glass.
DO NOT REMOVE INSERTS WHILE HOT. You need to hold the top of the handle with one hand while unscrewing with the other. You should only remove the inserts after cooling.
Be extra careful with water. The inserts and bead release filling the tube reduce the chance of a hot jet of steam, but do not eliminate it.

Preparation:

Slide the inserts into the handle. If you need to, back the clamp screw off a bit to get them in.
The inserts should be pushed all the way in, and the tips on the end should meet evenly.
Push the inserts flat against the top of a table with one hand, with the handle hanging off. This aligns them and keeps them co-planar.
Tighten the clamp screw. Moderate finger pressure is all you need.
Dip in bead release, up to the clamp, and dry.
FPI and Foster Fire Regular have worked well in tests.

Cabochon Construction:

Apply glass to the inside edge of the shape. Try not to get it on the top or bottom yet. Start at one point of the circumference and work your way around.
Fill in the shape. Repeat on the other side if needed.
Depending upon how thick you want it, add more glass.
Using mashers or a marver, flatten the shape to get the glass to flow and form the channel.
Don't go too far and push the glass over the outside edge as it may not be be possible to remove the inserts. This isn't a frequent problem.
When you mash glass it wants to form a circular shape. This is great if it's a circular cabochon. If there are points and straight edges, you may need to add more glass at the points, and less in the middle of the edges.
You can use the outside edge of the mandrel as a visual guide to the shape of your work.
Don't be surprised to hear "cracking" noises. As the inserts in the tube heat up, they can slide against each other. This can be confused with the sounds of glass getting too cool and cracking.

Cabochon Removal and Cleaning:

Soak in water.
Loosen the clamp. One turn should do it.
Pull your cabochon and the inserts out. You may wiggle them *gently*. Be sure not to bend the thin section that inserts into the handle.
If the inserts do not come off easily, place the cabochon and inserts on an old magazine or other sacrificial surface. Then take a small regular screwdriver and push in between the base of the inserts to spread them.
Remove the inserts from the glass.
A cylindrical 3/32" diamond tool is recommended for cleaning.

Cabochon Mounting: