Monday, November 21, 2011

Experimenting with Molded Glass Frit

A year ago I met Linda Steider, a glass artist who has come up with her own medium to use when molding glass frit. She graciously gave me a couple of samples to try.

I decided to use it a month later to create leaves for a fountain I was building. It worked very well, but I didn't spend a whole lot of time playing with it. At the next show where the fountain was displayed, a couple of guild members suggested I do a demonstration on this medium, so I agreed. That demo happened this last Sunday and this is to document the things I discovered while playing with the medium.

Linda uses glass powder when making her molded pieces. When I had done my leaves, I used fine frit and free formed the leaves. One leaf I let dry on a barrette mold for the curve, and I also fired it on that mold to keep the curve. For the demonstration I decided to use powder in the molds and free form a piece as well. Linda's blog lists her instructions for general use of her medium and more detailed instructions for using candy molds to shape the medium:

It suggests starting with a 50/50 mix of medium to frit, but when I talked to Linda she uses a higher ratio of frit. During the demo I used a 2:1 ratio of frit to medium. When it comes to getting the pieces out of the molds, Linda advises freezing the medium for about an hour. Then either letting the pieces slowly dry on their own or putting them in a dehydrator to speed up the process a little bit. For some reason, once I unmolded the pieces, there was added moisture, the pieces did not hold their shape, and they started actually melting! I checked with Linda, and she had never had this problem. My freezer is fairly new, whether it is that or the difference in elevation, I'm not sure. I found it wasn't my mixture ratio, because I compared a piece I was able to unmold before freezing and one after freezing from the same batch of mixed frit. The one that dried naturally before freezing was fine, while the ones from the freezer started to melt. So, I got around this problem by using my hair dryer on them as soon as I unmolded them. This helped dry them quickly and helped them keep their shape.  There were one or two that broke as I was moving them, so I tried to put them on a piece of glass glued together to see if they would be ok after firing. For my first batch, I used the following firing schedule:

375F to 1280F 20 min hold
Full to 900F 40 min hold
200F to 700F off

The results were ok, but I felt needed to be a little more shiny. Linda suggests holding them at the top temperature for more shine. The free form piece was not frozen, just allowed to dry naturally because I didn't used a mold.

The second group got slightly over fired. The second firing was as follows:

375F to 1300F hold 15 min
FULL to 900F hold 40 min
200F to 700F off

Some of the pieces lost their definition. Also, the piece I tried to glue together on a piece of glass didn't work quite so well. It came apart along the crack lines obviously. Not such a great piece, but maybe a good self portrait! :) And, I did like the shine, but the next pieces will not be fired to as high a temperature.

This is definitely a method you should try! To purchase Steider Medium go to Linda's website:

Would you rather make your own from scratch? Then go to Barry Kaiser's website, get a pass word and then read his tutorial on making your own glass clay:

There is also a commercial glass clay available, but of course, this limits your colors to what they choose:

If anyone is interested, I own my own glass forum on Yahoo:

Glass Fusion Group

Click on the link, tell me you read this blog or you're a member of GAGU and you'll be approved to join. Linda and Barry are both members and available to answer questions, and newbies and experienced glass fusers are welcome to join and ask questions or offer advice.

In summary, I'd recommend Linda's method to begin with. It's easy and fairly inexpensive but like any new glass technique needs a little tweaking with your own kiln and experience. I will try and add to this blog later this week with new pieces and let you know how I tweak my kiln schedule. Also, anyone who tries this method is welcome to add your comments and experience below. Thanks, Linda for allowing me to try this and share it with others!

Design by Duane Miles, beaded by Kerry