28 Jan Dragon’s first Melt!
Last Sunday was the day I had been waiting for for months—the first melt with my Dragon. We arrived at the art center around 8:30 and immediately started unloading the trailer and setting up. I had everything in position and assembled in about an hour. I hooked up the gas, and began the startup sequence—checking valves, turning on the blower, adjusting the air to the point it seemed to light up best on Thursday, setting the torch to point at the burner head, and then opening the gas valve. As I opened the valve and watched the needle gauge begin to climb, my heart raced. It couldn’t have been more than a couple of seconds, but everything slowed down for me as I waited for ignition. Then whoooosh, the flame roared to life all at once, the blower sound suddenly drowned by the sound of the flames.
I stepped back for a moment and then realized that I hadn’t put any glass in the pot to melt! I turned the gas off and let the flames go out. Thinking it would be easier to feed the dragon if she wasn’t breathing fire at me, I let her cool for a few minutes while I gathered the dragon food and a metal scoop to shovel it into the pot. I tried to pile the nuggets as instructed, with more to the edges of the pot and less at the center, but the pot is so small that it was rather difficult to get them to stay this way. Once the pot was full I went through the light up again. With flames licking the top of the glass nuggets I closed the door of the furnace.
I had a few small tasks to finish setting up, but for the most part all that was left was waiting for the furnace to get hot and the glass to melt. In most things I am extraordinarily patient, in this I was not. I was the closest I had ever been to blowing glass out of my own furnace and I just wanted to get to it! As the clock ticked away minutes, and minutes turned to hours, I got increasingly antsy. Having lit up just before 10:00, I expected to be approaching go time by 1:00. Around 12:30 I decided the wiser move was to go for a walk. Ed was at the studio so if anything odd came up he could call me back, so I was comfortable leaving.
A little after 1:00 we got back and the furnace looked less hot. I approached and opened the door, and discovered that I had run out of propane, there was no flame inside! With the noise of the studio glory hole Ed hadn’t been able to hear the sputtering sound of the emptying tank. It was a setback, but we had another tank on hand and got her lit back up as quickly as possible. With a window of 40 minutes in which it could have been off, my walk to avoid more waiting had backfired.
By 2:00 when I check, the glass was molten on top, but I could see through the clear smooth puddle at the surface to solid nuggets still in the pot. It dawned on me that the reflective glassy surface was insulating the glass deeper in the pot—by feeding the dragon when it was cold rather than preheating the pot I had further lengthened the time it would take to melt.
I was thankful that the open studio event went on with Ed doing demonstrations out of the studio furnace so that my exercise in waiting and chasing the learning curve could exist in the background rather than front and center. I had the opportunity to talk to people who were there about what the dragon was, and explain that it was the first time I was melting glass, but that it would be a fully mobile hot shop that could travel to events, street fairs, schools, etc. There was a lot of excitement about it which helped me stay positive.
A bit after 3:00, all evidence of solid glass was finally gone, and the bubbles that had formed the air trapped between the nuggets were rising to the surface. I decided that it was time to take my first gather—it was still stiffer than ideal, but it was hot enough to work with and I couldn’t stand to wait any longer. I moved my brand new blowpipes into position on the pipe warmer—hot glass won’t stick to cold metal, and less-than-fully-hot glass really won’t stick. I set out the colored frit and powders that I planned to use for my first piece.
My heart raced as I stood in front of the open furnace, pipe in hand, poised for the moment I had been waiting for. Slight yellow flames licking out of the mouth of the dragon, I perched the blowpipe on the yoke, and extended it towards the surface of the glass. I pushed the head of the pipe into the molten glass and began turning, gathering the hot glass like honey. I raised the pipe above the surface of the pot, continuously turning it as the glass trailed off until it broke free. Due to the lower than normal temperature I held the gather up in the flame for a few moments to add more heat, and then brought the pipe back to my bench for the first time. I blew into the mouthpiece of the pipe and popped a bubble into the glass.
As I inflated the bubble further I noticed that the inside of the bubble had taken on some color, which was unusual. It appears that there was some form of off-gassing from the brand new pipe, causing a silvery patina on the bubble inside. I let the glass cool enough to gather over, and returned to the furnace to get more glass. I plunged the glass bubble into the pot, turning the pipe as I did to gather as much as I could. The strange coating inside the bubble glowed bright orange from the heat when I brought it out of the furnace. As I blew into the pipe again the bubble grew and the silvery coating turned to tiny beads of silver with clear space in between the beads. As soon as I had seen the strange color I had abandoned my original intent to add colored glass to the piece, and instead decided to make an otherwise clear ornament to best be able to see whatever it was that happened on the inside. I finished shaping it into a ball, and opted to put it away in the studio annealer rather than risk losing the piece in the CAT-60 annealer that I had yet to attempt using.
I returned to the furnace to make a second piece, and to make the first piece I had intended to create—a dragon egg. I reheated the same pipe, to minimize the chances of another off-gassing, and took another generous gather. I shaped the glass with my new wooden blocks at the bench, popped a bubble inside, and brought it back to the dragon to reheat. When the glass was sufficiently hot I began adding coats of blue and turquoise glass frit, bringing the pipe back to the dragon to melt in each coat, careful not to allow any of the colored glass to fall into the pot. With nearly a dozen layers of color melted in, I gathered a thick layer of clear, and then added more coats of color—shimmering black aventurine powder this time.
When I was happy with the color I decided to make use of the bigger, hotter studio glory hole to get the piece as hot as I could handle much more quickly. When it glowed almost white hot and I lowered the glass into a bucket of water to crackle the surface. I held my thumb over the mouthpiece, trapping the air inside until I was sure the exterior was cracked and the interior still soft enough to stretch by blowing into it. I raised the pipe out of the water and blew hard, holding the end with the glass up in the air. The glass was stiff at first, but as soon as the cracks stretched apart, the warm glass inside inflated more easily. With the light of the sky behind the glass I could begin to see the blue glass interior shine through the cracks. I reheated, and returned to the bench to change the shape of the glass from spherical to egg-shaped with a wooden paddle and my jacks. For the sake of survival, I put this piece away in the annealer as well.
As I worked, the furnace continued to grow hotter, and the glass got softer. By the time I had boxed the first two items it was nearly 4:00, and the open studio event was officially ending. I had most of a pot (albeit a small pot) of glass to get through before I could shut down. I had a degree of uncertainty with the CAT-60 annealing tube, having never used any equipment remotely like it.
The tube pulls hot air from the furnace with a fan that is controlled by a computer attached to a pyrometer. The finished pieces are loaded through a door onto little train cars that allow me to pull them down the tube over an hour or so, progressively moving them further from the source of heat and allowing them to cool. In order for this method to work, the pieces have to be thin (less than ¼” thick), and small enough to fit. I made a couple of ornaments first, but decided that perhaps making some clear objects as test pieces while I learned the equipment made more sense. In the interest of time I designed a set of small clear air plant terrariums that I would open cold. I discovered how big was too big—one of the terrariums got jammed in the tube!
By the time I had a six pieces in the CAT-60 and it was pushing 5:00, I decided it was time to just pull the remaining glass out of the pot into a bucket of water, and shut down. We still had a three hour cool down before I could pack everything into the trailer, and a two hour drive home ahead of us.
With the pot empty, I turned the gas off, and began the shut down process. With pieces still in the CAT-60, I wondered whether shutting down would cause the temperature to drop too quickly. Fingers crossed, I continued pulling the train cars down the tube every five minutes. As the furnace temp dropped, I opened the damper a bit to allow more of the heat to enter the tube. One by one, the pieces came out—except for the one that got jammed they all survived! As things continued to cool, I broke the studio down and by 8:00 was loading the trailer.
All in all, the first day was a success. I learned a lot, figured out what my next questions and fine tunings were going to be, made a few pieces, and had a lot of fun (even the agonizing waiting for things to get hot was more like the anticipation of Christmas as a kid than anything else). I don’t think I stopped smiling the whole drive home.