Ting,ting,ting

[Bluebird]

I'm making a bubbler right now and Im taking it little by little so the piece doesn't crack. I'm currently letting the piece sit in at 1150 degrees. I'm hearing little tings and I know it's cracking. What do I do?

[STROKER]

what colors are you using? some colors dont like long garage times.

have you looked at it in the kiln to see if you can see where its breaking? if its something you can see then turn the kiln up to 1125 and let the piece sit in there while using the handtorch to fix.

crip fixed two good size cracks that way on my janky shit and it worked great.

bad melt in, or bad bridge seals can cause issues.

more details please.

[glassnewb]

Depends on the size and shape of the piece, the size of your torch, the colors used. Little by little isnt always the best. HOT and QUICK is how I tend to work. I took a class with Marcel and watched him wrap an Octopus one leg at a time around a huge bub. It was out of the kiln for AT LEAST 10 minutes. The neck to can weld also sheared off prior to adding the octopus and he raged it in a HUGE annealing flame and fixed it no prob...

If you think its cracking you have to find out where. Hold it up to a BRIGHT light. Get back to us once you isolate it. If its big cracks, trash it and learn why it cracked.

[Riley]

unless you're trying to strike out some color or momentarily ramping up to give you a little more working time, as during trying to heal an already cracked piece you shouldn't be kilning at 1150. and as said there are colors that will reduce eventually at that temp. leaving checks, cracks, or muddy colors.

when you are working a piece out of the kiln for longer than you should, placing it back into the kiln, the core temp is so low that a kiln at that temp can shock the glass. this isn't the case when all your welds are worked smooth and the piece has been made in such a way that you know there is no added stress.

kiln pieces at 975-1050 while working, depending on the colors. if it's a larger piece or a piece with varying thickness, attachments, marbles etc. you might try letting it be in the kiln for 5 mins or so in between working it.

depending on kiln space, i understand it's hard when you can only work that piece, and you get impatient between kilning and try and rush it. it's a classic scenario. if you find you have room left in your kiln, work on some attachments in the between times, or make a pipe or something. if you don't have room, maybe try doing some prep work where kiln space is not necessary.

anything to keep you from rushing your hard work and living that dissapointment over and over.

[Bluebird]

Thank you guys for your help but the bottom half of the bub cracked right off. I was using multiple frit colors on the inside. I also want to add that the bubbler annealed and I turned the kiln back on for a second round. I've done this before and what I made broke also. I learned today for the last time to finish the piece completely or keep the oven on. I will also keep in mind what you guys tell me here today. Thank you and repps all around!

[Braden Hammond]

some frits don't mix well together specially on the inside.... You also got to melt the crap out of it so that it's melted in all the way on the inside.

[CripSkillz]

look inside and make sure your frit was melted all the way in,, if not it will cause cracks also..

[Albino Sasquatch]

^^ what they said, and dont be scared to garage pieces now just do it at lower temps over 900 and not over 1000 is best. espically for sparkle colors that dont like being in the kiln at high temps all day long try useing the one color and make it all melted in or do smaller test mixes on a small bubble and if it cracks probably not a great mix try something else.

[ALIEN!]

I've had plenty of frit not melt in all the way on the inside and they were fine, no sharp corners, just not melted flush. The killer is certain frit colors just don't work well on the inside. Some will work, but don't garage above 980, I was having problems with chrome colors cracking on me, called GA and NS, they told me to turn it down to 980- 1000 (I was garaging at 1050) I turned it down to 980 for garaging, no more problems.

PS, worst color I ever used in frit is Aurora. EVERY piece I ever made checked in the color, usually around the neck where the piece was thickest. Beautiful color, but hates deep encasements.

[Bluebird]

But when you put it in the kiln at that temp (900-1000) and take it out to continue the piece, won't it crack when it hits the flame?

[TlkQ]

Heat it a little slowly and it wont be an issue. Hold it out at the end of the flame and bring it back in.

[ALIEN!]

generally speaking, if I give a piece 15 minutes in the garage at 980 I can stick it right into a raging flame and go right back at it. For something more touchy like something with sculpted work on it a half hour is better (like a salt style piece). At 980 your well above the stress zone and if left for 15-30 minutes most things will be very stress relieved and hot enough to go back into the flame.

[kage]

But when you put it in the kiln at that temp (900-1000) and take it out to continue the piece, won't it crack when it hits the flame?

bath the whole piece straight out of the kiln with a soft flame. then continue working as you would. and if you spend some time out of the kiln working a particular section, remember what has cooled, cause if you set that in a kiln at 1150, you will thermal shock the cool part of the piece just by setting it on the hot kiln shelf.
some people make the can and fully anneal, then asseble the next day.

[raven sun]

just want to help drive home two points made above...

DO NOT GARAGE ABOVE 1100, especially with chrome colors and in my experience, whites too... 910 is the strain point, 1080 should be max garage temp... i never have problems with garaging ten+ minutes at around 1050, just jam it into the flame and work deliberately heating right where you need to(no drifting)...

MIXING FRIT CAN BE DISASTEROUS, each color has its own COE, none are the same, they only play nice together cause boro is wicked strong and tolerant... BUT, there are clearly some combos that wont work well except in thin layers and maybe not even then... generally, more colors = more potential probs... in my experience, rough unmelted frit wont crack unless there are other mitigating factors, still, dont do it, melt that shit in...

also, if the bottom of your bub fell off, was it a clean break that followed the contour of the flat bottom?, if so, you may have sucked the heat out of the bottom with the graphite while flattening causing a cool ring in the glass where it can easily crack later... i suggest flame polishing after every contact with tools, especially graphite, as it is a heat sink...

[Bluebird]

Thanks guys. Really appreciate the help.

[VertigoGlass]

On my color pieces I will hold at 1050 and let soak between adding pieces. I dont advise bathing the whole piece in the flame as that can introduce stress back into the piece. pulling a piece right out of the kiln at 1050 i will work on the section i need to and only the section I am working on being cautious of your flame and the deflection of your flame. When I am finished with that section. I will open my kiln and let it come down to 930-960 with the piece held in the heat belching out of the kiln. Havent had any issues since i started using this tech. But your mileage may vary.