Finishing a Cylinder for Glassblowing

Video Transcript

" Hi! I’m Jim McKelvey with Third Degree Glass Factory in St. Louis. You can check us out on the web at www.stlglass.com. Today, we’re going to learn about glassblowing for expertvillage.com. Fern flashes the piece, then she’s going to bring it back to me. When she brings it back to me, I’ve got a couple of seconds, if I want to, to adjust the piece to see if it’s high. It’s a little bit high right there, and now it looks pretty even. You’ll notice that we’ve already shaped the bottom half of the cylinder. Actually, we’ve shaped the bottom 3 quarters of the cylinder. So all I really need to do to complete the cylinder shape is to heat up the top. Now, if the piece wasn’t made out of glass it would be real easy: I’d just heat up the top. But since glass tends to crack if it gets too cold, I’m going to have to remember to flash that punty occasionally to keep some heat down there as well. If the glass gets too cold it will crack, and we don’t want it to crack until the last moment when we’re ready to remove that punty. So, to heat a piece like this, I’m going to stay right in the front of the glory hole, concentrating on the heat on the tip of the piece. Occasionally, I take a flash, which means go all the way in for a couple of seconds and then come out. You don’t want that punty hot and moving around, but you don’t want it so cold that is seizes up and is prone to cracking. So, what I do is I stay here right until I see the tip of that piece start to round out and want to become nice and soft. You’ll also notice that as with the other times, I turn as slowly as I can, but still fast enough to keep the piece from falling off center. Okay, so the piece is looking pretty soft up there so I’m going to come back to the bench and finish this cylinder. Here we go. When you’re working on the punty, you don’t want to bounce the piece. You don’t want to knock it against anything. So, I’m going to start by lifting it with the jacks and slowly opening the tip. I open the jacks as the piece is opening and I’m almost there. One more reheat should do it. Now, when you reheat a piece of glass that’s on the punty, it’s generally a good idea to flash the punty as the first move. So, I go all the way in and make sure that punty get a little bit of heat. Then I can back out and concentrate that heat just where I want it. This one of the things that’s really nice about making cylinders, is because you’ve made most of the shape on the blowpipe. You can keep that back part out of the fire and keep it nice and cold so it retains it’s shape. What I’m going to do here is concentrate that heat, again, right at the tip. When I see that tip start moving, then I’m going to come out. One more flash here. I see the tip is moving nicely, so I’m going to come out and we’re going to finish this. Fern’s going to help be by paddling the lip, just a little bit, with a paddle. I’m going to ride on the sides. Okay, that’s good, and there’s our cylinder. "