first pot melt melt-down!

SWalsh · Post by **SWalsh** » Wed Feb 11, 2004 1:41 pm

I'm another one who has been lurking and absorbing all the valuable information at this website... my compliments and thanks to all. I also fall into the "slow learner" category and thought you might get a kick out of my first pot-melt experience. First attempt, I didn't schedule a high enough temp so wound up with a little drip halfway to my kiln washed clay pot bottom. Re-read about potmelts and increased the temp to 1610.... for about a 20 minute soak. (Can you see what's coming?) Cooled kiln and opened it to find a nice one piece pot, drip into pot bottom (which naturall won't come off!). Re-read and realized a little higher pot placement in kiln so I'd get a nice 3 inch drip but now the clay pot is up in the air by about 2 inches so decided to "gamble" that it wouldn't break when the glass melted enough to gently lower the pot bottom to the kiln shelf (HA!!!). When I opened the kiln after annealing overnight, I had broken pot bottom and melted glass all over the place. Naturally, I hadn't kiln washed the shelf posts so still have to clean them up. I was so disgusted that I tossed the whole thing and wrote it off as "oh well, had too much black in it anyway."

Still, I'm game to try again and want to thank all for the posts (which I should not only read in the future but memorize and, maybe, tattoo them on my forehead!

Sue in Bucksport, Maine

charlie · Post by **charlie** » Wed Feb 11, 2004 1:51 pm

better learning through experimentation

never throw away glass. i had a pot break. i took all the glass covered shards, sand blasted off the clay remnents, and reused the glass in another pot melt.

you can clean the glass off the kiln stilts the same way. if they're really heavily coated, you can also suspend them up in the air, heat to 1650, and wait for the glass to drip off. that'll give you little tiny melts that you can use in other projects, and you'll only have a little bit of glass to blast off the stilts.

SWalsh · Post by **SWalsh** » Wed Feb 11, 2004 2:55 pm

The kiln posts aren't heavily covered but I didn't think to melt the glass off. Figured on old fashioned chipping away so you saved me some trouble. Thanks.

Sue

Mark Hughes · Post by **Mark Hughes** » Thu Feb 12, 2004 9:53 am

Be sure to read Randy Wessner's posts on pot drops. A lot of good info!

gone · Post by **gone** » Fri Feb 13, 2004 1:04 pm

Does your kiln have a peephole? You can learn a lot about glass by actually watching what it does.

SWalsh · Post by **SWalsh** » Fri Feb 13, 2004 5:14 pm

Els, yes I have a peephole. I have an Evenheat 14-6 with Rampmaster II, which I bought from Delphi in Lansing, MI. It was the largest I found there which would run off regular household current (110?). I'm trying my first drop ring vase today. I have someone at home so set kiln for 300 dph until 1300-- and I should be home by then. Still, set for 2 hour soak but plan to sit and watch the glass slump. It's about a 4 inch drop but I wish my kiln had more depth to it.

Question for all: this kiln doesn't seem to like to ramp up fast... is it cuz it's not a 220 or heavy duty electical line kiln? Didn't want to have to do special wiring but now wondering if I made a mistake. Opinions welcome. Thanks,

Sue

charlie · Post by **charlie** » Fri Feb 13, 2004 5:20 pm

SWalsh wrote:Question for all: this kiln doesn't seem to like to ramp up fast... is it cuz it's not a 220 or heavy duty electical line kiln? Didn't want to have to do special wiring but now wondering if I made a mistake. Opinions welcome. Thanks,

Sue

how fast is not fast enough? if you set it for 300 dph, does it do that? what does it do when you fire afap (9999 dph on my controller)? how fast do you need it to ramp?

the rate is dependent upon interior volume and element contruction. the 120v sets the limit on both the size and construction of the elements, which can be a limitation. if the kiln is too large, then it ramps slow. if it's really small, it can ramp fast.

SWalsh · Post by **SWalsh** » Tue Feb 17, 2004 9:25 am

Charlie, I tried a 2 step program that I saw (somewhere)-
750 dph til 1250, soak 20min (to minimize bubbles), ramp 750 dph til 1500, soak 30 min. flash vent til 1000 and let it cool on its own from there.

If I'm figuring right, it should take about 2 hours and 50 minutes before I would want to vent it but my kiln was still creeping up to 1500 degrees at that time. Looks like I was off by half hour or better on when I expected to vent. Was I?

Thanks,

Sue

jerry flanary · Post by **jerry flanary** » Tue Feb 17, 2004 11:34 am

This is where what you want (the program) and reality (the capabilities of your kiln) collide. Similar things happen all the time, say between an architect and a contractor or an engineer and a mechanic...

I don't see any side elements in the picture of Evenheat 14-6. Is it just the one in the top? if so, that's a lot of bricks to heat up to 1500 w/ 12 Amps 110v. Just relax and you will learn what your little pile of bricks can do and how long it takes to do it.

SWalsh · Post by **SWalsh** » Tue Feb 17, 2004 2:54 pm

It has just the top elements, none on the side. I know each kiln is different so sorta glad it's just me getting to know my kiln. I took a class from Nancy Tang of Glass Orchids last year and would hate to wind up being so bad at this that Brad Walker takes back the book he signed for me when Nancy got my copy from him! I do love the experimenting, posts on this site and looking at others works.

Sue

charlie · Post by **charlie** » Tue Feb 17, 2004 6:06 pm

SWalsh wrote:Charlie, I tried a 2 step program that I saw (somewhere)-
750 dph til 1250, soak 20min (to minimize bubbles), ramp 750 dph til 1500, soak 30 min. flash vent til 1000 and let it cool on its own from there.

If I'm figuring right, it should take about 2 hours and 50 minutes before I would want to vent it but my kiln was still creeping up to 1500 degrees at that time. Looks like I was off by half hour or better on when I expected to vent. Was I?

Thanks,

Sue

i use
600 1650 30.
9999 970 45
50 840 0
100 700 0
off. don't peek or open kiln till cold.

no need to flash. long anneal because usually it's not 1/4" but 3/8 or more. you don't need a hold at 1250. that's for a double layer fuse.

i get about 3-4 uses out of a clay pot before it breaks. of course, you have to be aware of the leftover glass colors and use similar ones in that pot in the future.

also, you can enlarge the hole, or cut a slot with a side grinder to make different looking melts.