Hot enough or too hot?

daffodildeb · Post by **daffodildeb** » Sat Sep 06, 2003 1:27 am

I'm frustrated by my efforts to "read" my fused pendants in the kiln. I have no controller, so I'm having to look at the pieces to determine when they're done. The trouble is, I'm getting too much fuse--no texture. I'd like to tack fuse or go a little past that, but apparently I'm either way too hot (max 1350), or too long (varies). I do vent after they seem to be done, but I think I'm doing this way too late.

Any advice for a newbie fuser? I am planning to get a new kiln with a controller, or at least a controller for my existing kiln, but I think I'll still have to figure out the balance between heat and soak time...

Kitty · Post by **Kitty** » Sat Sep 06, 2003 2:01 am

deb, maybe your pyrometer is wacky. for your next project, forget the pendants. set up some one-inch squares, with decorative elements on top, and do some test firings and see what's wrong (or right). you dont need a hold for texture-fuse. if it looks good, shut that kiln off and walk away. i know it's frustrating when things dont work out, and getting the new kiln will be a god-send, but for right now, i urge you to do some test firings. for my kilns, 1450, 1470, 1480 are the temps for texture-fuse, and 1500 for smooth surface. i only do texture-fuse on earrings, never on pendants -- temps can vary depending on the glass, some is softer than others. a little log book with notes might help with this persistent and annoying problem. good luck with your experiments.

Mike Byers · Post by **Mike Byers** » Sat Sep 06, 2003 8:39 am

Good advice from Kitty. Also, get yourself some graph paper and record a time versus temperature plot, recording the temperature every ten or fifteen minutes. Make a note of the types of glass used and a little sketch of the pieces on this graph, as well as info about the end results. Then when you get the effect you want (assuming your pyrometer is consistent) you'll be able to reproduce these results. This is a good idea even with a controller, particularly with a new kiln.

Amy Schleif-Mohr · Post by **Amy Schleif-Mohr** » Sat Sep 06, 2003 9:13 am

I agree with all that has been said and just wanted to add one thing. You may already know this, but the tack temp. will vary on what color of glass you are using. The best example of this is black and white. White is so much harder that it just takes longer or hotter to get it where the black is. I also wanted to let you know that my experience is with BE glass, this could absolutely differ with other glasses.

Amy

daffodildeb · Post by **daffodildeb** » Sat Sep 06, 2003 9:31 am

Amy, does this mean that you should only fuse or tack fuse similar questions together. I mean, how can you stop "cooking" on one when another's not done? And what about multiple colors within the same piece?

Mike, it's not that I can't look into the kiln and see the right point, it's more that it seems to go from that fuse level to blah in nothing flat, even with venting. That's the frustrating part, not to mention the wasteful part.

Kitty, I think you might be right about not doing a soak--and this may be where I am running into trouble. Do you vent when you get to that point?

I appreciate all the suggestions--maybe I'll get through all this eventually...

Geri Comstock · Post by **Geri Comstock** » Sat Sep 06, 2003 9:37 am

It sounds to me like maybe your pyrometer is giving you incorrect readings...

After you fuse for a while without a pyrometer, which was how I learned, you can tell by peeking at the glass by it's color and appearance. If the top temp you're taking it to now is 1350 by the pyrometer, try dropping back to 1300 and see what you get.

I don't believe you mentioned how long of a hold you had at the top temp, but you can also decrease that time as well.

Good luck! You'll be so happy when you finally get a controller! It makes things so much easier!

Best -

Geri

Amy Schleif-Mohr · Post by **Amy Schleif-Mohr** » Sat Sep 06, 2003 9:47 am

Deb,

I didn't mean that you couldn't fuse two different colors together in the same piece at all. I just wanted you to be aware that some colors are harder than others and take longer to fuse.

Amy

Amy Schleif-Mohr · Post by **Amy Schleif-Mohr** » Sat Sep 06, 2003 9:50 am

I forgot to add, that the bottom line is that you have to experiment. You will find out that everyone on this board does things differently. But it's good to ask so that you can brainstorm about the direction you want to go and try to limit the experimentation so that you don't waste so much glass and energy.

Good luck
Amy

Kitty · Post by **Kitty** » Sat Sep 06, 2003 3:20 pm

deb -- i make one style of earring that has four tiny parts laid up on a rectangular base. the instant i see that the batch of earrings looks good, i shut the kiln off. if i fail to do this, the earrings come out with a smooth surface, very boring.

the heat in the kiln is so great, the glass continues to soften and the shape change, even after the power is cut. over time, you will learn to cut off heat a wee bit before you see that things look as you want them. jewelry pieces are small, and things happen very fast. there's another minute or two of full fusing time in a small kiln, after the power is cut. my jewelry kiln is about 8x8x8 inside, brick walls, and i know it will over-fire from retained heat if i dont pay attention.

also, forgive me for asking you, but with all this looking into the kiln, you do have a pair of goggles to wear for this, eh? nag nag nag.

yer pal, kitty.

Lynne Chappell · Post by **Lynne Chappell** » Tue Sep 09, 2003 12:36 am

So you're looking in the kiln and it looks just right. When you say you vent, do you mean lifting up the lid? Until the temp drops a hundred degrees or your shirt catches on fire? If that is the case then you're misreading the degree of texture left, because that certainly should stop the melt. If you just mean turning off the kiln and taking out a peephole, then I guess you need to stop a bit sooner. Getting a digital controller isn't really going to help you any. In fact, it probably makes it harder, because you tend not to watch. In either case, if you want repeatable results, then take everyone's advice and keep good notes.

daffodildeb · Post by **daffodildeb** » Tue Sep 09, 2003 12:55 am

Kitty--it sounds like you have the same or a similar kiln to mine--AIM? I will try stopping things a little sooner. My attempts over the weekend were a little better.

I know some people have mentioned goggles. Can you or anyone tell me what I should be looking for and what kind should I get? What is the danger? I already use regular glasses, which are supposed to provide UV protection. And I don't exactly stick my face into the kiln--just lift the lid a few seconds to see what's happening, while keeping a good distance.

Lynne--I vent by lifting the lid away from myself until the temps have dropped to about 1100. Of course, the kiln is off at this point, too.

In the last few days I've been reading that venting degrades fire brick. If this is so, should I just turn off the kiln before things look "right" or what?

The only thing I really want the controller for is to reduce--not stop--the number of times I have to look at the kiln. I would like to have a way to ramp up in a controlled fashion until I get in the general neighborhood of what I want, and then ramp down in a controlled fashion to anneal. As it is now, I have to make lots of runs upstairs to see if it's even reached 1300.

Kitty · Post by **Kitty** » Tue Sep 09, 2003 1:41 am

when we're talking about small jewelry parts, you dont need much of a schedule, nor much specific annealing. the way i fire a batch of jewelry is i heat it up to 500F over about 20 or 30 minutes, especially if it's the first firing of the day. this burns off any Klyr Fire or other liquids. then i fire AFAP to about 1490F (my kiln might be different than yours for this top temp), shut it off, and walk away. the only time i vent it is if i'm in a big hurry, and want to hurry things along. mine cools from 1500 to about 1000 relatively fast. if i'm jamming, i crack the kiln at 1100 or 1000, and bring it down to 500. at 500, i take the shelf of jewelry out and set it on top of the kiln. you cant do this with big stuff, only with small jewelry pieces. dont do it with pendants. small earrings can tolerate this abuse.

i have a Cress front-loading kiln, which is actually an enameling kiln, but works well for jewelry. i've been firing it constantly for six years, and it has been quite the work-horse. it cost about $660 new. i've also got a big kiln, but i never use it for jewelry.

i believe the glasses you need are #3. go to a welder's supply place, and tell them you're looking at incandescent glass. they'll advise you. you might check the Tutorial at the top of the screen, right next to the yellow box that says Warm Glass Weekend ... there's probably mention in there of the # you need for these glasses. you really must do this. looking at hot glass causes cataracts over time. the glasses are cheap, too. about $15.

Kitty · Post by **Kitty** » Tue Sep 09, 2003 1:46 am

deb, read this link. scroll down to the part about glasses. i think mine are #3. the first pair of goggles i bought were too dark, and i couldnt see anything. they would probably be good for raking hot glass. the ones i have are #3, i'm pretty sure, and they go on over my own glasses, sort of like safety glasses. so check this out:

http://www.warmglass.com/safety_equipment.htm

daffodildeb · Post by **daffodildeb** » Tue Sep 09, 2003 1:55 am

Thanks, Kitty. Looks like it's time for another trip to my friendly welder's supply place. And they really are friendly!

Kitty · Post by **Kitty** » Tue Sep 09, 2003 2:05 am

back in my younger days i was a carpenter. i found out then that guys like to sell tools and materials to girls. i think they're sort of surprised to find out what we're up to, and that contributes to the friendliness, which is always nice. haha... i was just remembering that one job i had for a printmaker was in loft space where another painter had hired a girl to build his studio out for him, so the two of us women were up there with these kinda involved projects. the other woman looked like a model, and in fact put herself through a couple of years at a very expensive design school working as a topless dancer, because it paid $10 an hour 35 years ago, and that was a lot of money. we got some real friendly advice when we went to lumber yards and hardware stores together. lol. the good old days.

daffodildeb · Post by **daffodildeb** » Tue Sep 09, 2003 2:12 am

Don't knock it! Back in the old days when I had a figure (you HAD to ask how many decades ago, didn't you?) I was very involved in flying and sports cars. I had my license years before my to-be husband. Can't fly anymore, but still have the '64 Porsche he was driving the day we met! We're restoring her now, in fact.

Also, I was an aeronautical engineering student at Purdue--400 guys and ME. But that's another story. Strangely, I didn't date--could have had something to do with studying...

Can you tell I never played with dolls?

daffodildeb · Post by **daffodildeb** » Thu Sep 11, 2003 7:01 am

A followup--with more questions. Last night I did another firing of pendants made up of a base piece, top pieces, and two small strips of glass on either side of the hole, which is formed by a bead release dipped piece of wood skewer.

The good part is that I was able to fire and retain the qualities of the glass. The bad part is that I didn't quite get enough fusing--it's more of a tack fuse, and there are pieces of glass that overhang instead of drooping more like I wanted. I think I'll have to grind off some areas and refire.

What do you folks recommend for maintaining the hole? The wood has burned out, leaving a nice cavity for the chain, but in order to refire the pendants I'll need to insert something else. I have some thick shelf paper--should I wedge a strip of this? Or is there a better solution?

Also, if I have achieved a good tack fuse, about how many degrees more do you think I needed to achieve a bit more of a fuse--it's Bullseye glass and dichro. My temp gauge said 1300, and it seemed to be "there" so I shut it off and walked away. Should I have gone to 1350--or would I have lost the texture I was trying to preserve? I realize this is a hard question to answer, but I'd like some guidance, especially since I've had so much trouble with overfiring.

Patricia O'Neill · Post by **Patricia O'Neill** » Thu Sep 11, 2003 9:36 am

You never said what type of kiln you have.

Is it one of those hotbox type kilns? because the temperature indicated is always lower than the real temperature. When you work in a hotbox it is different that with a kiln more traditional.

You need to have protection glasses to look inside the kiln. Not only to protect from the heat (the regular clear glasses are not good) but to protect against the infrawhatever (forgot the name, it's early morning..).
I purchased mine at a discount site referred a while ago by Tony Smith. Not beautiful but very efficient and at a real discount price. You could spend as much as $120 for Auralens and those are the same at $12.

I'll have tips for you if you are using the hotbox.

Patricia

Sara · Post by **Sara** » Thu Sep 11, 2003 11:56 am

My opinion (trust me I have an opinion on everything) . . . the best thing anyone new to fusing can do is work without a controller for the first few years. I did this and learned so much about the behavior of glass. the biggest drawback I encountered was that without the controller it was most difficult to actually be consistant.

I didn't see where you mentioned your firing schedule (or missed it in my rapid perusal of this thread)

1. start with many different colors in your kiln, layed up as you normally would and fire as you per usual, I have my standard 6 colors. My recommendation, low and slow, works for me for consistant small pieces every time. choose an arbitrary top end point. look at the pieces and see which one is fused the way you want them all to be.

2. starting with the 'perfect' one notice which ones are underfused. do a second firing with only the colors that are underfused . . . add 5 minutes. check when at top temp and decide if that's enough time. remember to let them be a scosch on the underdone side since you won't be venting . . . when you get the desired look this is your schedule 1 for softer glasses, in my case, black, turq, sky blue, emerald. If I'm being particularly anal I'll fire only turq at the lowest of temps.

3. starting with the 'perfect' one notice which ones are over fused . . . decrease 10 minutes, check at top temp and decide if you need to add another minute etc. until you decide if the reduction time is enough. dink around with this and eventually you'll have your top end or schedule 3 temp. schedule 2 would be the 'perfect or mid range temp'.

When I put multiple colors within a particular piece I'll average the top end temp. Of course I haven't added the hot and cold spots of a particular kiln into the equasion, sometimes it is simply a matter of doing many many, heck, literally hundreds of firings to really know how a particular kiln will behave. We have 5 kilns and each one has its own personality and charts.

I tend to fire lower and slower than many and have found that for the look I want this is best.

lastly, I only have built in controllers on 2 kilns, the other three have their own stand alone controller and I prefer this. One kiln is the first one I purchased 15 years ago and it still hummms to perfection, and it's controller is really an old box wall version.

good luck,

Sara

daffodildeb · Post by **daffodildeb** » Thu Sep 11, 2003 2:27 pm

Thanks Sara--I'll try your suggestions. I'll refire in different groupings. Now, what about the problem of the hole, since I can't just put the same size mandrel in place (the last ones were wood and burned away).

Patricia, I have an AIM--about 8 x 8 interior dimensions. Yes, I did get the welder's glasses that are recommended.