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What are Lampwork Beads?

"Lampwork" means glass that is formed and decorated in a torch flame hot enough to melt and work the glass.

The "lamp" in lampwork came from the oil lamps and blowpipes originally used in seventeenth century France and Italy. Blowing by mouth or with a bellows into an oil lamp flame with a small  pipe makes just enough heat to soften and form the soda lime types of glass. 

Today lampworking is done with a fuel gas (usually propane or natural gas) and oxygen torch, hand tools and molds to decorate and shape the glass.

 These are homemade torches built from brass pipe fittings.

torches and tools

The torches and the small kiln used as a bead annealer

torches and annealer

Lampwork beads are made by winding glass rod or strips that are softened in a torch flame onto a metal mandrel (rod). The mandrel / rod  has been dipped in a bead release, a clay-like mud that hardens up like a  brick in the heat of the torch. The bead is then shaped and decorated.

winding glass on mandrelreheating beadshaping the bead more shapingreheating after shapingdone

After the basic bead is wound on the mandrel / rod it's often decorated with more hot glass or metals for different colors. Sometimes the decorated bead is encased in clear glass. The tricks and moves used to form and decorate the glass haven't changed much in Centuries.

 The bead release keeps the glass from sticking to the mandrel while you're making the bead.  It also lets you break the bead loose from the mandrel after the bead has been annealed and cooled. Bead release is fragile once heated and cooled so it breaks loose easily (if the bead release has been formulated well) so you can get the finished bead off the mandrel by holding the mandrel with pliers and twisting the bead.

You can buy bead release ready made:

Or you can make your own:

Let it sit overnight before using.

You can "tune" this recipe. If the release crumbles while you're working on the hot bead, add more flux to the mix so the other ingredients melt together together some more.

This makes it harder to break the bead loose when you're done, so increase the amount gradually until the bead release is tough enough hot for your style of working but not so tough you have to fight it to get the bead loose when it's cold.

You can get the materials (except the diatomaceous earth) at a potters/ceramic supply.

 The diatomaceous can be found at pool supply stores.

Once the bead is made it has to be annealed by cooling it down slowly in an annealer (I use old kilns for this) so it doesn't have a lot of internal stress that would cause the bead to shatter or crack later.

When the bead has cooled, it's broken off the mandrel and the bead release that's left in the hole is cleaned out. The easiest way is something like a Dremel tool with a diamond tool bit used wet or you can use a hand reamer .

Go to the "Lampwork Bead How To Article" in the site index if you want to see all the pictures with explanations.

Here's something for the more advanced Lampworkers...

This was an article I wrote for the Glass Art Society Newsletter Sept./Oct. 2003

It's something I made to get around the problems of lampworking dense, high lead colors like the color bars furnace workers use.

oxy propane lampwork torch with compressed air

Here's a little something I've found to make my flameworking torches more versatile. It's really not anything new, the flameworkers in Europe have been doing it for a while.

The idea is to combine compressed air with the oxygen or gas to produce a softer and colder flame that is much gentler on the soft glasses. Most of those gorgeous colors in soft glass were never designed to withstand the high temperatures found in a pure gas and oxygen torch flame. These colors react to excess heat by doing any number of rude and ugly things such as burning out the oxides, turning brown or surface pitting. Another benefit is that things happen more slowly in the cooler flame.

The picture makes this look a bit more complicated than it actually is. All I'm doing is putting compressed air that is controlled by a needle valve into the gas line just before the torch. In the picture the compressed air line comes in on the right side where you see the white plastic line and the brass quick disconnect.  The line then passes under the torch, and connects to the needle valve (green knob in the picture) you see on the left side.  After the compressed air has gone through the needle valve it goes to the brass tee where the air is mixed into the gas in the red gas line just before the torch.

 It only requires a small amount of compressed air volume and pressure to do this. There is not much strain on the air compressor. All that is needed is compressed air coming in at a higher pressure than the gas or oxygen.

I also use an inexpensive air flow regulator at the the air compressor to lower the air pressure. It's not in the picture. I can run this torch setup without the regulator but the lower pressures available with the regulator make for easier adjustment and less fluctuation of the flame. Changes in the torch flame can happen with no change in the needle valve position by having the compressed air pressure going up and down as the compressor cycles. Any kind of regulator that is set to a pressure below the lowest tank pressure will help smooth this out.  I'll eventually upgrade from a flow regulator to a pressure regulator to help further minimize the pressure and flame changes.

A needle valve can often be found inexpensively at salvage places. If that doesn't work I buy them new from Carlisle. They used to be around $20-30 but it has been a while since I bought a new one.  Carlisle knows them as "Fine Thread Metering Valves". Their part numbers on these run from 16A001 to 16A015, depending on what size pipe thread they fit and if they are straight or a ninety degree angle.  You can find Carlisle at  www.carlislemachine.com.  If there is an arrow on the side of the valve it needs to be pointing in the direction of the air flow when installed. This keeps the pressure off the shaft seals when the valve is not open.

The plumbing and hoses I used on the torch in the picture are a "late night special" composed of what I had available on the shelf. All the brass is common pipe fittings like you would find at a building supply or auto parts store. The red hose is welding torch hose. The white and black hose is plastic semi  truck air brake line with compression fittings. A heavy truck parts supply store is a great source for a wide and unusual variety of compression fittings and that plastic air brake line. The air brake line comes in a number of sizes, is incredibly tough and is very inexpensive. Commercial heating and air conditioning suppliers usually have these too. Many commercial building heat/air systems are controlled by compressed air.

I usually use pipe fittings when I can. It's always so much quicker and easier to hook everything up with things that I can get locally. I use teflon tape to help seal the pipe threads. When I converted this torch the only needle valve available at the time had compression fittings so I had to mix, match and adapt the fittings between pipe and compression. Compression fittings can be an advantage when I want to position something exactly. Pipe thread fittings don't do that as gracefully.

I fire the torch by lighting the gas and oxygen mixture and then very gradually letting a tiny bit of compressed air into the flame. A large variety of adjustments are possible and the compressed air adjustment is very sensitive. Too much compressed air will just blow out the flame.

The flame can fool you, it can look nice and blue and still be reducing. I check the flame for reduction by melting a piece of white opal glass in the flame and then seeing if it shows any brown or black stains. I've also found that a large flame will often reduce things close to the torch head but is just fine further out in the flame.

I ALWAYS use a backfire preventing safety valve on the gas line where it goes to the regulator just in case something goes wrong and the flame burns back into the hoses. I get the backfire valve from the local welding supply.

Different torches like different things, so, no telling what a particular torch will be the happiest with, air in the gas or air in the oxygen. It's easy enough to switch the air injection over to the oxygen line and see if a torch might be happier that way.

 I never would have known just how easily this could be done unless my friend Sky Campbell had been game to do a little "investigative surgery" on one of his imported bench burners. Thanks Sky!