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Maiden Bisque Witness Cone 05 06 07 Melted To Washed Shelf

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My maiden bisque fire.... Yes I am a newbie. I deeply appreciate any advice I can get. I don't know any experience potters in my area. Yes I am in the heart of the Smoky's, but I don't know any area potters. I am trying to live my dream, making pottery in the mountains. Not selling just making Christmas, birthday, ect gifts.

 

Clay Highwater Pheinox I think cone 6. Kiln used Paragon B88A. Babysitter broken, I have the pieces.

 

I followed a firing schedule given to me by a previous instructor using self standing witness cones. 7pm bottom low crack lid, 6am close lid, 7am top low, 9am both medium, 11am both high, 4pm off.

 

Mistake #1 place witness cones away from peep hole. I thought it was so hot I could not see them. So I followed schedule, well almost. I heard what I thought was a pop so I shut it off at 3:30pm.

 

Later this evening I peeked lifting the lid and quickly closing, seeing I did not see a glow any more. All three cones were melted on the shelf.

 

Question 1- how do I remove the cones from the shelf?

Question 2 - top layer of pottery seemed intact - will bottom layer be intact, too? Or does bottom run hotter and desaster may loom?

Question 3 - If all is intact will I have glazing issues? If so, what can I expect?

Question 4 - I have the babysitter parts. I wonder if the previous owner ran it like that. The ceramic piece that holds the two pins the cone bar sits on can be placed back in hole line up break so snug. Can I run it like that?

 

I am an Analyst by trade so sorry for the formality. I just want to give you everything at once.

 

Thanks so much..... Alice

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Grinder/angle grinder will remove the cones from shelf.. wear appro. safety gear for lungs, eyes and hands.

The "glow' disappears around  500 Deg Celsius so not a great gauge of safe temps to open.

Most folks wait till below 200deg. Celsius to crack a kiln.

Top  layer can be the hotter layer,  so the lower layers may be either better or underfired......

What cones were melted. If the bisque is too hgh in temp you may have troubles getting glaze to apply to the pots.

Your kiln sitter if reassembled should be tested for correct setting by using a disc through which the pin and the 2 supports you write of sit whilst engaging the trip mechanism on the outside of thekiln 1?16th inch grip. this is from memory..

Should get such details from  your maker, or the kiln sitter maker may be better!!

Testing coming your way fast! :)

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Question 1- how do I remove the cones from the shelf?

Question 2 - top layer of pottery seemed intact - will bottom layer be intact, too? Or does bottom run hotter and desaster may loom?

Question 3 - If all is intact will I have glazing issues? If so, what can I expect?

Question 4 - I have the babysitter parts. I wonder if the previous owner ran it like that. The ceramic piece that holds the two pins the cone bar sits on can be placed back in hole line up break so snug. Can I run it like that?

1. You will need to grind the cones off the shelf using an angle grinder or other tool (but a grinder will do it faster and more easily). After you have removed the cones, you will need to reapply kiln wash to the area.

2. Just remember, it is only clay. And, you don't have disasters -- just learning experiences. Some kilns fire hotter at the bottom; some fire hotter at top. If something is broken, it is more likely due to a structural issue -- Phoenix can be fired up to Cone 10 and it is doubtful your kiln reached that temperature.

3. Glazing may be impacted by the apparent over-firing of the bisque. To what degree, it is hard to tell. Highwater's Phoenix is a cone 7 to 10 clay body. So, unless you reached near cone 10 to vitrify the clay body (doubtful from the info you provided), it will be absorbent for glazing. Use one piece as a test, do your normal dip in the glaze and, after the glaze has dried, scratch through it to see how thick of an application you got. If the glaze is too thin, you'll need to do a longer dip.

4. You will want to get the kiln sitter fixed and installed . . . it will make your firing life much easier.

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Babe... Thank you very much for the good information. All 3 cones were melted flat to the shelf. I will try to get a hold of Paragon tomorrow. The main bar pin is intact. It is just the ceramic tube that holds the two pins that broke.

 

Bciskepottery... This was a big lesson learn. Thank you for all your good information. I will be brushing the glaze on instead of dipping. Will that make a difference? I hope Paragon still has the parts. I will get a price if they do. I think this kiln was made in the early 70's. The woman that owned it before me fired porcelain painted ceramics. Unfortunately she has passed, before I had it hooked up.

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If you were bisqueing to cone 06 and had 07,06 and 05 in the cone pack and they were all flat then you might have only reached 03 or thereabouts so you could still be okay.

 

If you touch the tip of your tongue to a bisqued pot your tongue should stick a little to the pot, a bit like when you lick a not too frozen popsicle. Not very scientific but it works. If your tongue doesn't stick then the clay is too tight to take a glaze without a lot of fussing and usually lands up with unsatisfactory results.  

 

YouTube video from Paragon on replacing kiln sitter tube: 

 

Good luck and welcome to the forum.

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that sounds like the kiln i started with in 1972.  if you have no other resources, try the paragon website and print out their instructions, a cone chart, a sheet that allows you to record the info for each firing, etc.  you have not mentioned your previous experience with firing, if any.  i don't understand the reference to "formality" but if you are apologizing for using more than 12 words to describe the problem, please use as many as you need.  another alice

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Thank you very much Min..... I really like "you touch the tip of your tongue to a bisqued pot your tongue should stick a little to the pot, a bit like when you lick a not too frozen popsicle. Not very scientific but it works. If your tongue doesn't stick then the clay is too tight to take a glaze without a lot of fussing and usually lands up with unsatisfactory results." I will try that.

 

And thank you for the utube address. I will check it out.

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Someone else's firing schedule will only work for the turn-up schedule of the firing. How long it takes to get to temperature will depend entirely on your kiln. a small kiln will typically get to temp much faster than a large kiln. It may hit temp only an hour after turning everything up to 'high', or it may take 4 hours or more. You have to watch the cones or use the sitter to turn it off at the correct time.

 

If the cone support bars will sit snugly in the sitter tube, then it is probably useable. Post pictures if you can.

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If you were bisqueing to cone 06 and had 07,06 and 05 in the cone pack and they were all flat then you might have only reached 03 or thereabouts so you could still be okay.

 

If you touch the tip of your tongue to a bisqued pot your tongue should stick a little to the pot, a bit like when you lick a not too frozen popsicle. Not very scientific but it works. If your tongue doesn't stick then the clay is too tight to take a glaze without a lot of fussing and usually lands up with unsatisfactory results.

 

YouTube video from Paragon on replacing kiln sitter tube:

 

Good luck and welcome to the forum.

 

I watched the videos they were very helpful. Gave me confidence that I can fix the babysitter on my own. I also did the tongue thing and it really did not stick. Will I know right away that the glaze is not going to work or will I not know until I fire the pots and have a mess.

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Someone else's firing schedule will only work for the turn-up schedule of the firing. How long it takes to get to temperature will depend entirely on your kiln. a small kiln will typically get to temp much faster than a large kiln. It may hit temp only an hour after turning everything up to 'high', or it may take 4 hours or more. You have to watch the cones or use the sitter to turn it off at the correct time.

 

If the cone support bars will sit snugly in the sitter tube, then it is probably useable. Post pictures if you can.

 

Hi Neil.... Here are pics. Today was a Monday which is a different way to spell crazy. I did not get a chance to call Paragon. Thanks so much for helping. I really cannot complain seeing I picked it up for $150. The rod is still intact. Not sure if you could see it.

post-71225-0-51392300-1443479001_thumb.jpg

post-71225-0-76847100-1443479018_thumb.jpg

post-71225-0-10562400-1443479037_thumb.jpg

post-71225-0-51392300-1443479001_thumb.jpg

post-71225-0-76847100-1443479018_thumb.jpg

post-71225-0-10562400-1443479037_thumb.jpg

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alice, are you using commercial glazes?  

 

do you have a cone chart to look at?

 

to what cone will you glaze fire your work?

 

what instruction have you had and can you contact that person?

Good evening Alice.... I have Amaco Potters Choice glaze and will brush on.

I do have a cone chart to look at.

If I can glaze this batch I would fire to Cone 6.

I have emailed one of the instructors I had and have not heard back. The other instructor just had a baby and I do not feel comfortable contacting her. This is her first baby and I am sure her hands are full.

 

I am going to try reseating the sitter tube until I can get another. I am not sure if I have to trash this batch. I am hoping not because I have a couple of cups I would like to try to save for a girl at work.

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I also did the tongue thing and it really did not stick. Will I know right away that the glaze is not going to work or will I not know until I fire the pots and have a mess.

Try applying some glaze. If the pot absorbs the water and the glaze sticks, you'll be fine. If the pot does not absorb the water, then try warming the pot in the oven/microwave and then brushing the glaze on; the warm pot will cause the water in the glaze to evaporate and leave the glaze materials behind. The key is warming (not heating). In a normal bisque, the pot is porous enough to absorb the water from the glaze. If your pot will not absorb the water, warming is an option.

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do not think only the worst.  your pots might come out perfectly fine.  bruce has suggested a great way to check out the possibility that everything is ok, just bisque fired to a hotter temperature than you intended.   what makes you think you will have a mess?  factory fired wares are bisque fired to much hotter temperatures than the final glaze temp so do not imagine you will have a puddle when you open the kiln on the glaze firing.   what is it you imagine will fail?

 

it sounds like you are imagining what i have seen, puddled work stuck on a kiln shelf.  that was because the CLAY was intended to be fired to cone 06 and was actually fired to cone 6 several hundred degrees hotter than the clay could take. highwater Phoenix clay goes to cone 7-10.

 

people refire work all the time even if it has been taken to the top temperature, it is just a little more difficult to make the glaze stick BEFORE firing.  warming it at the lowest temperature in your kitchen oven and brushing on  a first coat of glaze will allow you to add the second and third coats more easily.  that oven temp is enough to burn your hands so be sensible about handling the warmed pot with a pot holder.  

 

this is a simple situation, someday you will laugh about it.  before that, change your clay body to one that matures at cone 6.  there are lots of posts here about why.  check them out after this is all over.

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Did those cones ever get fried! 

 

Judging by the colour of the light in the kiln plus the totally melted cones I'm guessing you went far past bisque temps.  

 

I know it's possible to glaze this load, albeit with more effort than if it was bisqued properly, but if it was my work I would chalk this up to experience and move on. (and use a ^6 clay for your ^6 glazes)

 

http://www.ceramicartdaily.net/PMI/KilnFiringChart.pdf

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I will try to glaze this load. Thank you for all the great encouraging words. I will not be able to fire for at least a week. I have a funeral a ways away this weekend and maybe fire the following weekend. I cannot express my great appreciation to all of you and I will post pictures of the glazed pieces. Thank you thank you.

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+1 for Min and Mark's recommendations. Good luck with the glazing.  However, if you find out that the the pots are so over-fired that they will not readily take glaze, then its best to learn from what happened, correct it, and send this load to the shard pile (caveat, if there is something in the load like a piece of sculpture that was extremely complicated/time intensive, it might be worth trying to glaze it).  

 

Sadly, we've all had something like this happen.  Trust us when we tell you that It will be a better use of your time and energy to make new pots.   

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I think you went too hot for them to take glaze well, but it's worth a try. I didn't realize the sitter tube was broken in half. Yes, you'll need to replace it. There are a lot of different sitter tube lengths and configurations, so make sure you call the manufacturer to get the correct size.

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You will need an wielders infrared glass or kiln glasses from a ceramic supplier to view the cones safely.

I would as Neil said call the kiln company and get the right sitter parts.Also only use large cones for viewing in spy plug and small cones for sitter use this is a key point.Where your cones (in puddels small or large ones?)

Mark

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I agree 100% about fixing the kiln sitter. Every Newbie should at least have that on their kiln. It is on order and the next firing will have the sitter.

 

Wow what an adventure. I cannot thank all of you enough for all the valuable advise I have received. All of you have no idea how supported I feel. I started this post with such lonely, hopeless, and scared feelings. I was desperate, and thinking I was not capable of doing this out on my own. Thank you soooooo very much. I hope everyone of you feel the great energy you have instilled in me. I can and will do this and continue to make wonderful gifts. Thank you thank you!!

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