Making Glass Lace

Very frequently I turn scrap glass into frit.  (Separate tutorial) One day I thought I would try to turn some frit into sheet glass. Regular art glass comes 1/8” so that is what I sought to make. I carefully spread out some frit and fired it to full fuse temperatures.  When I opened the kiln I was very surprised to see that my sheet of glass was riddled with holes.

My initial disappointment soon turned to wonder. Why had it occurred and could it be repeated and/or controlled?  The why was easy. Glass wants to be 1/4” thick so the surface tension caused the molten glass the contract leaving random voids. (It’s the same reason two single thickness pieces won’t fuse edge-to-edge.)  The repeatability question took a few tries.  Essentially there are two critical factors. One is the size of the frit used and the other is how thick/thin it is layered on the shelf.

The craters (holes) produced are not very interesting by themselves. However, when combined with another technique I was playing with at the time, which I call “veining”, the effect has possibilities.  ”Veining” is done by covering frit with a solid layer of powder.  This will produce an web-like coating when the glass fuses and surface tension moves the powder.  I like the way the webs flow and concentrate around the craters when these two techniques are combined.  The results are random and controlling them is touchy.

This tutorial shows the making of a piece of “lace” (or “crater”) glass combined with the veining. The result is pretty useless of itself but it can be used as a component in a subsequent composition. Many of the bowls I have made lately are experiments in the use of this lace glass.

             (Click to enlarge the pictures)

I begin with a layer of frit.  Here I’m using medium sized frit spread very thin and sparse.  Notice there are even some open areas between grains of glass.  There is no formula but note taking will help. I normally weigh my frit on a precise (nearest gram) postal scale.  By spreading a predetermined amount of frit over a measured area you can get repeatability.  This is a 14” stainless steel ring, from Matt Hoppes, used as a form. It will be removed before firing since there is no reason for a dam.

Then the frit is covered with a generous blanket of powder.  It looks like a lot but it will thin out. I use a tea strainer to sift the powder over the frit. In this example I tried for a uniform covering but other times I have varied the coverage and/or used different colors of powder.  There are lots of artistic possibilities available by varying the powder density and colors combined with changing the color(s) of the frit. The most difficult part of applying the powder is getting the edges to come out the same as the body, or not if that is your intent.

Now it is fired to full flat fuse and held a short while for the glass to flow and contract.  (I won’t give firing schedules because every kiln is different.)  When it comes out you’ll have a piece of lace (cratered) glass with veining running over the surface and around the craters.  The veining tends to concentrate around the holes because the glass has contracted after the powder was moved by the surface tension.  I like the effect and know of no other way to achieve it.

It is necessary to clean the bottom side because there will be some kilnwash dust on it.  (Also check the inside edges of the holes because as the glass moves it sometimes brings up some kilnwash with it.)  This can be difficult because, as you might have guessed, it’s kind of fragile. The fragility of the lace depends on how “holey” you made it. I have had some come out so cratered that there were islands within the body of the piece.

What to do with it?  The lace I made in this tutorial was laid on a 16” - 17” circle of single thickness black glass (BTW, all the glass in this piece is Bullseye.).  This composition is then fused. I only took it to a contour fuse or slightly above.  I didn’t want to go so high or hold so long as to cause the glass to flow and smooth out. I intended to have the texture of the craters become a part of the design. I also didn’t want the edge of the single layer black circle to “dog-bone”.  The blank was then slumped into a BE mold (#8651). 

Because the frit used was clear the black shows through a veined, lacework of yellow.  It is a lightweight bowl because it is only a little more than single thickness.

I wouldn’t say the possibities are endless but there are lots of things you can do with the lace.  I have experimented with filling in the craters with frit and/or powder, combining transparent and opalescent glasses, putting the lace on top of iridescent glass, putting lace on top of lace with/without filling in the craters, etc. You may, now, be able to discern how many of the bowls pictured on this website were made.  If not don’t hesitate to ask.