Low Fire Clay, THIS IS WHAT HAPPENS!

brendamvilla · May 23, 2019, 2:16am

I have gotten a few questions asking what happens when you fire low fire clay to the temperature we glaze fire (cone 6)? This is what happens:

What kind of damage does this cause to our shelves and equipment? This kind of damage:

Please do not bring any low fire clay into Ceramics to be fired at DMS. Our firing team has no way of knowing just by looking at it. No low fire clay means no low fire clay. It’s a Committee rule. If you are not sure if your clay is low fire, please ask someone or simply DO NOT USE IT. We explain all of this in our Ceramics Orientation 100 - Welcome to Ceramics! class. Please sign up as it is a required class to be able to use the area. This was voted in a Committee Meeting and passed unanimously by all committee members that attended.

dryad2b · May 23, 2019, 3:03am

Actually, I’m betting that this was not a fire-able clay at all. Which means this person REALLY needed the Ceramics 100. The last time we fired a low-fire clay piece in a glaze kiln, it just slumped a bit, and didn’t “boil”/bubble at all. Maybe air-dry clay???

I’m pretty sure I wasn’t at that meeting. I remember it being discussed at a meeting I was at, but I don’t believe it was called for a vote at that meeting. Could we put it back on the agenda? No rule will protect us from random uninformed folks dropping in.

meanbaby · May 23, 2019, 4:02am

Thanks. Ceramic team for your time cleaning that up.

Beth, It was voted on at a meeting 2 months ago, It’s a good rule. Since some Makers have low fire clay special permission can be obtained from the Chair for people that know what they are doing to use low fire clay.

At the time it was my understanding, It was not voted on because of possible melt downs, it was because Clark was bringing his mixer to recycle clay. He was insistent that no low fire clay go into his mixer. I’m kind of lost on this since I missed the last meeting because I was home on medical leave, but the last meeting notes reflect Clark was giving pricing and profit info for ceramics to buy a pugmill and sell clay? I do hope to get caught up on the next meeting.

Kala-Mari · May 23, 2019, 11:33pm

That kind of a mess has to be avoided. Appreciate all the volunteers who pitched in time and effort to clean that up.
How about a kiln maintenance class, so all users know what it takes to keep it going?

dryad2b · May 24, 2019, 4:54am

No. There really is no way this could have been avoided. We don’t have any restrictions on what goes on the shelf, and someone who was totally out of touch put something on the shelf to be glaze-fired. My personal guess is that that was air-dry clay. I’m not sure how we’d reach some one who is that seriously uninformed and out of touch with the committee and community. The current sign might help, as it does include the “if you don’t know, ask”. Although, if they are so clueless as to put air-dry clay in a kiln, they might STILL put their piece up to be glaze-fired, because they ARE sure it isn’t low-fire!

It’s one of the side-effects of 24/7 access, and no employees. Nobody’s around all the time that people are here, so the random clueless person gets in.

And, as @Monikat said, there’s no way to know what clay has been used when you’re putting stuff in the kiln. These accidents are rare enough that it’s not worth doing more than the signs we’ve got right now. There are enough that even those folks who don’t really see or read signs should notice those. There’s always that 1%, though…

The reason I think this was air-dry clay is that it is substantially different from the last time somebody put some low-fire clay in a glaze kiln. (It’s been at least a couple of years.) That piece was just barely beginning to melt. It had slumped a little bit, and become one with its’ cookie, but it was still a bowl, and the glaze was okay. This stuff is just crazy.

meanbaby · May 24, 2019, 2:27pm

I agree Beth, moving forward hopefully the 100 class will help in prevent this from happening again. I don’t think we should add more rules or classes for the committee for something that might happen every couple of years by 1 person.

@brendamvilla If you find out who the piece belongs to, I will be happy to volunteer to spend some one on one time with the person getting them up to speed.

Kala-Mari · May 24, 2019, 4:51pm

On the other hand, sharing a thought: over-teaching can cause over-confidence. Do you think early success due to intense coaching can lead to such decisions.
Or, one more for the Ceramics manual😉:
Name your clay under your name on the bat?

Mars42 · May 24, 2019, 9:28pm

#forbiddensnacks. That looks like a lava cake.

Anette_Henningson · May 24, 2019, 9:34pm

lol, didn’t try to eat it.

Anette_Henningson · May 24, 2019, 11:48pm

Maybe to clarify, put “low-fire bisque to cone 04 only, if you have questions, please ask” on the bisque shelf, and “mid-fire glaze to cone 6, if you have questions, please ask” on the glaze shelf.

Monikat · May 25, 2019, 12:53pm

Ceramics 100 does talk about the types of clay we use, the shelving system, and where to place 04 vs 6 pieces. This is why it is so important all members (new and existing) who want to utilize ceramics area take the class. There are weekend, evenings, and day-maker class times just for that purpose. It’s also a case of “If you see something, say something”.

Anette_Henningson · May 29, 2019, 1:25pm

Paragon is beeping

JBluJkt · May 29, 2019, 1:41pm

Kilns throwing error again. @Team_Ceramics

Nathan_Jones · May 29, 2019, 2:36pm

I occasionally work in low fire at DMS, but I’m always careful to segregate my slop and trimmings. (Not saying this was my bowl, I haven’t put anything to be glazed in months.)

Having the option of working in low fire is one of the reasons why I came to DMS and started building up the pottery area. There are ways to work responsibility with the medium, but therein lies the problem: it takes individual responsibility and caution.

meanbaby · May 29, 2019, 3:53pm

Nathan when the vote was taken, it was agreed the chair would allow seasoned potters to use low Fire clay, I also have piles of it. This also has to do with proper disposal of the low fire clay since at some point Clark was/is going to bring his mixer to recycle midfire clay.