Kiln programs

[DCSY1551]

I have been working in soft glass, self taught for a year+ and am wondering if maybe some of you might post your kiln programs for Boro and Soft. I have been working off one that I found here for soft and love it. I'd like to try Boro and am wondering what is a good program for that and what others use for soft glass. I have a paragon Bluebird.

I love this sight. Thanks so much for all your help!

Dawn

[kevingreenbmx]

The cycles I use can be seen here: https://wiki.hive13.org/view/Paragon...mpworking_Kiln

[DCSY1551]

Appreciate the direction!

[jesnbec73]

For 104, I do a full ramp to garage at 920, then a full ramp to 960 for annealing at which I hold for 90 minutes or two hours depending on what's in there, then for beads I ramp down 250 an hour to 800 and hold for ten minutes, ramp down 80 per hour to 700 and hold again for ten minutes, then 250 per hour to 300 and off.
If I have larger marbles in there, I will slow the '250' ramps down. It's probably overkill for beads, but I usually have a couple small marbles or something in there with them. I don't have a schedule for boro, but am going to need to start looking into it soon as I have recently upgraded my torch and want to start doing some tube soon.

I have a box of marbles that all have issues that need fixed, puntil marks, lens ripples, indents etc. Since we're on the subject, what is the maximum ramp upwards to a working garage temp they would take, the largest of them is probably around 1-1/2 inch? I was thinking 250/hr?

[echeveria]

I never go above 910 for soft glass. Effetre recommends 878, Double Helix says less than 920 to preserve striking and reduction effects, Bullseye is in the 890 range (don't remember exactly, and their technical pages are a pain to navigate, and are incredibly technical because of the casting and fusing usage.) I think for larger work, the hold time becomes more important than a higher temperature, and the 960F seems to be an urban myth.

I have a friend's program for boro. She did a lot of kiln striking because she used a smaller torch. I would consider this suitable for beads and pendants and small marbles. I have no clue what would be suitable for functional pieces.
Garage @1150
Hold 1 hour after all work is done
Ramp down to 1050, hold 1 hour
Ramp down @ 200 deg/hour to 700, hold 20 minutes at 700
Ramp down @ 200 deg/hour to 150, shut off.

[kevingreenbmx]

Originally Posted by echeveria

I have a friend's program for boro. She did a lot of kiln striking because she used a smaller torch. I would consider this suitable for beads and pendants and small marbles. I have no clue what would be suitable for functional pieces.
Garage @1150
Hold 1 hour after all work is done
Ramp down to 1050, hold 1 hour
Ramp down @ 200 deg/hour to 700, hold 20 minutes at 700
Ramp down @ 200 deg/hour to 150, shut off.

1150 for an hour is HOT and LONG for boro... I get slumping of my cup stems if I hold 1075 for more than 15-20 minutes.

I will sometimes do a 5-10 minute hold at 1100-1150 to initiate a strike in striking colors, but I go to that temp then back down to 1065ish as fast as the kiln will go, and then hold the 1065 for as long as the color needs to strike (30-40 minutes for easy strikers, a few hours for some more stubborn strikers)

[echeveria]

Originally Posted by kevingreenbmx

1150 for an hour is HOT and LONG for boro... I get slumping of my cup stems if I hold 1075 for more than 15-20 minutes.

I will sometimes do a 5-10 minute hold at 1100-1150 to initiate a strike in striking colors, but I go to that temp then back down to 1065ish as fast as the kiln will go, and then hold the 1065 for as long as the color needs to strike (30-40 minutes for easy strikers, a few hours for some more stubborn strikers)

I am assuming most of her beads stayed at 1150 for a few hours since it was her garaging temp

[rcktscientist]

From my calculations, boro can be kiln crashed up to 0.4" in thickness, meaning the slow ramp rate (annealing) is generally faster than the kiln cooling rate so the glass doesn't pick up stress. Just remember that a flat, 0.2" thick item on the kiln floor is effectively 0.4" in thickness! So my rule is: if the beads are less than 0.25" from bead hole to outer surface and you 'anneal' on a rack, you can just crash the kiln. Same for marbles but they can be 0.4" in diameter, they also benefit from a rack to allow even cooling on all sides. I have proven this works but I encourage you to try it so you can get started with boro without the schedules issue.

[kevingreenbmx]

Originally Posted by echeveria

I am assuming most of her beads stayed at 1150 for a few hours since it was her garaging temp

Beads are probably fine just because they are such a stable shape, but that heat would definitely slump most blown work I think. I'd also be worried about any of the chrome-bearing sparkles or greens, they like to shift COE when held in the kiln at those temps