Drop Ring: parfait glass - WarmGlass.com

Drop Ring: parfait glass

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Drop Ring: parfait glass

Postby KaCe » Thu Feb 04, 2016 3:59 am

I am going to run a test this week. I've read and read, and hope to find someone with experience doing these to give me a thumbs up or down on my idea.

I've read that you can plan 2" of drop per layer of glass. That isn't enough for a parfait glass. I am using BE 7" mold. I cut the glass 5.5" (as I didn't want a large lip)

Speaking of glass lip. I've read and read and can find nothing to indicate that one needs a lot of glass for a lip, yet there it is in all the photos of work, unless it has been removed. So I wonder if it is the source for the glass that gets pulled downwards? I think I'd still have enough even with the glass cut very conservatively. But...

can I put a another piece of Tekta on this already full fused blank so that I have more glass to meet the 2"= 1 sht? I even was wondering if the glass could begin just a half inch from the hole; when fused it would surely almost all be pulled down. Or am I looking at this all wrong?

While watching the BE tutorial on drop ring molds I saw that they recommend 1/16" fiber paper. Is this necessary? What is the purpose of it? My mold is freshly kiln washed.

Using BE dark royal purple transparent, tekta in a Skutt 1414. I have made a "cookie" for the piece to drop onto that would serve as a flat foot for the glassware. I'm decorating it with lime green Glass Line paint.

I'm excited for tomorrow, when I plan to fire it, but it will take me all day to get this done, and it may be my first of several tests. TIA.

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Re: Drop Ring: parfait glass

Postby Brad Walker » Thu Feb 04, 2016 9:18 am

If your rim is too small on a deep drop the glass can slip off the mold and down through the hole. You usually want a 1" rim on all sides. If that's bigger than you want in the finished piece you have to cut the rim off after the drop.

Your blank needs to be thick enough to handle the stretching that will occur during the drop. If it isn't thick enough the glass will get too thin during the drop. To get to the right thickness you should add some more layers of glass (usually a clear) and refuse (dammed).

Warren Weiss
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Re: Drop Ring: parfait glass

Postby Warren Weiss » Thu Feb 04, 2016 11:39 am

I recently did an 8" drop through a kiln shelf that I cut a 12" hole. The "ring" was coated with kiln wash and did not require the 1/16" fiber paper. I used the "rule" of 2 sheets for the first 4" and a layer for each additional 2" drop for a total of 1/2" thick blank. The drop worked but the glass was too thin close to the lip. As a result, when I tried to cut off the lip with my tile saw, as Bullseye shows, it broke. Fortunately, it broke all the way around in a jagged circle (approx. 1" variation) which I was able to finish with a wavy top. I am going to repeat this bowl with a 3/4" thick blank. Take away: the formula used above was insufficiently thick and if you create a lemon, make lemonade.


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Re: Drop Ring: parfait glass

Postby JestersBaubles » Thu Feb 04, 2016 3:34 pm

If I understand one of your questions correctly...You can put a blank circle on top of the fused circle, but the effect will be different than if you prefuse the blank to the existing circle first (take a look at Paul Tarlow's ebook on drop vessels -- it's actually a really nice effect and one I need to play with).

One of the keys to keeping the rim from thinning is to set your process temp low and drop very slowly. You'll more likely get an "even stretch" at lower temps. Also, if you decide to do this again, take into consideration the effects of heat work on dark vs light colors in your design. (The BE video mentioned this, I believe.)

Dana W

Valerie Adams
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Re: Drop Ring: parfait glass

Postby Valerie Adams » Thu Feb 04, 2016 5:39 pm

I thought I remembered something about 1/4" of glass (two layers) needed for 1" of drop...

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Re: Drop Ring: parfait glass

Postby KaCe » Fri Feb 05, 2016 2:37 am

I am not disappointed with the replies I just got. Thank you ALL. A friend, Penny, (thank you, Pen) gave me some 1/16" fiber, so I'll use that. I hope I can use it more than once. The BE video shows them stripping it off the dropped piece and throwing it away. (I'm so Scotch-apologies to the Scottish on the board- I can't throw it away if it is useable again.) Can anyone tell me why they threw it away, rather than putting it aside to use again?

I appreciate the low and slow advise. I plan to put a cookie for a foot, so will place it on some 1/2" fiberboard which will make my drop 5.5". I will add another layer of clear to the Dark Royal Purple Transparent. (I'm not sure if it will react more like a black because it is so dark, but I am expecting it to do just that.) I have decided the 100°F/hr > 1245°F and then watch it closely. I think that at that slow of speed I can put it in tonight and then check it before bedtime. If the temp is low and slow, I'll get up early and watch it. I figure about 10 hours from when I put it in it will be showing signs of movement. So in at midnight, and then I'll get up at 9AM to begin monitoring. I wish I had made two blanks and had two molds. I'd love to see what the difference would be between cut Tekta set on top of the fused blank vs a fused blank with Tekta on both sides. I am anticipating that the DRPT (Deep Royal Purple Transparent) will have a bit more transparency than it currently does when stretched, which I'll like.

Thanks for the lead on Paul Tarlow's ebook. I think while this "test" is cookin' I'll download and read what you suggested. As I don't have a circular dam, I think I'll try the Tekta on top the full fused blank... I'll see how that looks. I'll also make sure I have at least 1" on the rim, which I think is just right. (I actually think I have slightly more. I have 5.5" of glass and the hole is 3".

Okay. Cross your collective fingers... I'm pulling the trigger on this test. Love all of you and send many thanks for the advise from each of you.

Kevin Midgley
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Re: Drop Ring: parfait glass

Postby Kevin Midgley » Fri Feb 05, 2016 12:31 pm

Even with a kiln computer controller, there is one essential thing, well actually 2 things.
1. Eye protection so you don't get cataracts.
2. A clip to your shirt kind of electronic kitchen timer.
Without the timer you will be sure to have a puddle. That a 99% guarantee,
You may be setting it for '10 seconds more'.

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Re: Drop Ring: parfait glass

Postby KaCe » Sat Feb 06, 2016 10:00 am

Thank you for the heads up. I have my phone set for a 15 minute alarm. I check the kiln and take a photo. So far it's been 26 hours... though that isn't all at 1225°F. After reaching that temp and holding for 6 hours, I forgot to add time, and when I went out to photography failed to notice that it was cooling. (I'd gotten lazy, my notebook was filling quickly with a lot of nothing happening, so I had decided to note changes as the glass began to move. I think it MAY be beginning to move, so I'm upping my checking to 10 minutes. But I'm dog tired. I really need to figure out when to sleep... reverse engineer the project to begin it at the right time of day. (I thought I had, but that's an error, too.)

I am excited to see how it turns out after all this time. I did use ColorLine glass paint to write names on the glass. I tried it with a glass cap, and on the surface. I want to see how the writing turns out. I may have written too large.

I can say without reservation that I am learning a lot with this project. Oh, I may have neglected to say that the project is to make ice cream parfait glasses for a wedding in 7 days. Nothing like a bit of pressure to push an artist to get the work done. And it, of course, is a family member... our daughter, who is getting married and I'm making them glasses for their ice cream (instead of wedding cake). More when there is something to report.

Again thanks.

Posts: 126
Joined: Sun May 15, 2005 2:25 pm
Location: Old Town, Tacoma, WA

Re: Drop Ring: parfait glass

Postby KaCe » Sun Feb 28, 2016 4:35 am

This is the third time I've tried to update my post. The previous two said it was saved to drafts, but I've looked and looked and can't find my drafts. So here I am again. I was having issues with my photos not posting, too, so I reread the forum questions... which is always a good thing to review.

So the "test" glass was two layers prefused. Then I decided I needed one more layer of glass and opted for Tekta. I cut the same size as the two fused were originally. I figured it would fuse while slumping through the hole. You can see in the image of the two parfait glasses that the test one has a noticeable lip from the Tekta. It also as more lines. The first of my "real" parfait glasses I fused three layers and slumped them. You can see the surface of the rough parfait shape is very smooth. The air bubbles in the three sheet fusing were small, rather evenly distributed. [img]1st%202%20parfait%20glasses-sm.jpg[/img] You might also notice that the "test" glass has lime green Colorline that I used to write the names of the bride and groom. But it remained mostly in the area that will be cut off. The "real" glass I used silver foil. I like how the silver foil turned out, but would have liked the silver to come up higher on the glass. You can see some of the silver turned yellow... which I don't mind.

What I am posting about now is the air bubbles that began as small seeds, are now stretched out and I am concerned about them being points of weakness. I am thinking if the air bubbles are on the surface when I cut the excess ring off, it will leave an open air pocket... which perhaps clear Colorline could fill. I'm not sure if firing the Colorline will ruin the shape of the parfait glass, but that is one of my questions for this board. Will it? Is there anything that folks do if there is an air bubble where you don't want it?
[img]ParfaitBubbles-sm.jpg[/img] Here you can see the seeds of air that have stretched to long lozenge shapes.

When I cut off the lip I'll post about that. First I have to make the second one. I am pleased with the evenness of the sides. I think the advise of low and slow was very good. I know I could have fired it hotter, but it seemed a good idea to let the glass get nice a gooey over a long time so more of it was inclined to flow down the hole. Thanks for that advise. More when I've made the second one.

Oh, BTW, I've decided that while the newly weds thought the glasses would be too small, I think they will be an elegant size for ice cream and less likely to foster excessive servings, which is nice for all of us. I'll measure their capacity when they're done. I am really enjoying this learning experience. I also am grateful to all who make suggestions. Thank you.
1st 2 parfait glasses-sm.jpg
test and first try on parfait glasses
bubbles near the edge to be trimmed
before lip is cut off

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