How to use fusible tape and shelf paper around fusing dams

I wanted to share with you a fantastic new use that I've discovered for the fusible acrylic tape that I sell on the Glass Art Tools website.

Recently, I've been producing thicker fused pieces out of multiple layers of glass.
However, as as all fusers know, molten glass will want to "pool out" to an even 6mm thickness unless it's contained within restraints or "dams" during fusing.

Whenever you use a dam--such as those made of firebrick, ceramic (such as mullite/cordierite), or even metal, you have to line the dam with a material that molten glass won't stick to.  The traditional resist material has been fiber cloth, also known as kiln cloth or fiber blanket. This material has a consistency similar to felt, and comes in varying thicknesses.

Unfortunately, traditional kiln cloth has a couple of drawbacks. One is that you have to run it through the kiln separately first, to burn off the binders. Then you can use it with your glass. This is an extra step that ties up both your kiln and your time.

The other drawback is that if the cloth stands higher than the pile of glass next to it, the top layer of glass will tend to "stick" to the cloth, forming a ragged edge (shown below) that has to be ground off and either cold-polished or fire-polished with another run through the kiln. This is a lot of extra work.
ragged edge

I try to avoid extra work whenever possible, so I came up with the idea of using regular
kiln shelf paper instead of kiln cloth. I attach the paper to my ceramic dams using our fusible double-sided acrylic tape:

I use ceramic dams to hold in my glass, and cut the kiln shelf paper (I use Bullseye Thinfire Shelf Paper, but you can use any fusible shelf paper) so that it would fit around three sides of the dam.  (If you're planning to put glass on the outside of the dam, you could of course cover all four sides.) Make sure the paper lines up with the far edge of the dam, unless you want to cover the edge. In that case, you can create a "tab" that is folded over the edge and taped in back.

I then cut three little pieces of the Fusible Acrylic Tape and put them along each narrow side of the ceramic dam, as shown in the photo above. The tape will stick to the ceramic as well as the paper, and will burn off in the kiln, so it's perfect to use.

Fold the kiln paper into a crisply scored line along the edge, and then press dam and paper together. Fit the paper as tightly as you can (without tearing it) around the dam and tape it to the other side. Here you can see one side taped:

Below is a photo of the dam setup I used to create a three-layer (9-mm) thick fused glass cross-brace (two layers of clear glass and one layer of opaque black). In the lower right corner, outside the X, is the place where I used traditional kiln cloth to fuse a 3-layer square component, whose ragged edge is visible in the first photo in this article.

The result, after a very slow full-fuse with a prolonged anneal and cool-down sequence, is lovely and precise. Below is a closeup of the fused edge (two layers of clear glass and a top layer of black) which was formed next to the paper-wrapped ceramic dam. This is exactly how the glass looked coming out of the kiln. It will be used as a structural piece, so it needs no further work. Note the pretty, semi-polished surface texture.

Below is another shot of the finished piece. Clearly, the use of kiln shelf paper wrapped around each dam and attached with our acrylic fusing tape:

  • saved time in assembly
  • formed a nice straight edge
  • saved time in additional polishing/coldworking
  • provided easy cleanup--just tilt each dam over the waste bin and the shelf paper slides right off.

Some additional tips:

--Before firing, be sure to look carefully along the inside walls of the dams to make sure no ceramic is exposed to the glass. If you've missed a spot, just cut, fold, and tuck in an extra piece of kiln shelf paper where needed.

--Before you close the kiln door, make sure your glass is perfectly in place, and gently squeeze together the opposing walls to make sure they are flush against the glass.

--This setup shows 3 layers of glass. When fusing more layers, place a firebrick outside each dam to hold it in place.

--Always experiment to make sure this technique works in your specific kiln, and for your specific application.

Have fun!