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  2. I gave up on trying to look in to see the cones, but I think it helps to remove them to cool that last 200 degrees, other than that I have no use for them since I use a vent. I have a solid one that came with the kiln, only sticks out 1 inch or so, they could all be like that as far as I'm concerned.
  3. So obviously we need peep holes from time to time, but why are there so many, and when I'm doing brick repair, can I just get rid of some of them. I leave my top peep open, I like to see a cone drop. But the rest are kind of a waste, and when I break one with my shin, I'm wondering A. Why don't I be alittle more careful B. Why can't I plug that hole with something that doesn't protrude into the path of a shin, thigh, hip. Please avail me of thy kiln wisdom.
  4. Bill Van Gilder talked about this in one of his videos, said the foot ring acts as a fulcrum, pulls the rim down and the base up. He makes the base slightly concave to compensate.
  5. Maybe, just never have seen a timer speed up.
  6. Today
  7. I still love my drycleaner bags, I can't remember the last time I actually drycleaned anything, but it didn't keep me from stopping in one and asking if they had any discards. I'm still using them, and that was 5-7 years ago, with a bag of them still in storage lol. They are light, they drape well, I double, sometimes triple them up to control drying.....and sticking with the subject, my workbench is clear, I'm ready to start again, pitchers are the need for this week
  8. Thank you Bob...why do you think it is the kiln sitter? It has never tripped, unless I have removed the cone from the brackets. That’s why I was thinking it was the limit timer. I was hoping that setting it on 12 would eliminate the issue (previously, I had set it per Cress’ recommendation at about 1hr longer than the expected firing time-between 6-8 hours). Prior to setting it to 12, the kiln had always shut off after 2-3 hours. To me, it seems as if the kiln is firing for slightly less than half of what the limit timer is set for....
  9. Sounds like your sitter needs adjustment, cleaning and checking. All the power comes into the sitter so if it trips, everything turns off. There are several you tube videos out there that may be helpful, search kiln sitter if you are a DIY er. My guess is the slightest bend of your cone shuts it off prematurely. Maybe a bent rod, but service just the same. I believe your wiring diagram below and a screenshot of the manual. Both are available on the Cress site.
  10. Staying off topic We have Kenyan Hansen here for today and tomorrow for our residents. Should see some nice soda work Monday morning by all.
  11. I recently purchased a second hand Cress FX-911 kiln. It has a kiln sitter and a Firemate Control. I have been trying to fire it for almost a week. Yesterday, I had some success, but something is still not right. I was firing to 04, to bisque fire some cookies and test the kiln. By setting the limit timer to 12 (the longest setting available), the Firemate to C (medium), and the thumbwheel to 1, I did manage to get the elements to heat up to red hot, and the kiln sitter cone bent a little I don’t have a pyrometer, but based on the cone (see pic), I’m guessing that the kiln got to around 06 after about 5 hours of firing. What happened yesterday, and has happened in the past, is that the power to the kiln shuts off (the light on the kiln sitter goes off), but the kiln sitter has not dropped, and the time on the limit timer has not elapsed. The kiln is plugged into a GFCI outlet, which has not tripped. I’m thinking maybe there is something wrong with the limit timer? I eventually would like to fire bisque to 04, and glaze fire to 5. Help!
  12. Bill: results from Ougland & Brindley study on heat work. 2192F (1200C) minimum further development of the clay body after this point. Minor decreases in absorption, along with minor increases in glass content. See chart below. Typical cone six ramp hold temperature for maturity. ----------------- --------------------- 2192F (1200C.). Glass 62. Silica 21. Mullite 19 2372F (1300C). Glass 66. Silica 16. Mullite 21 (Ougland & Brindley) Off topic, Ron Roy emailed me: he is doing a work shop nearby in June. Looking forward to seeing my friend. Tom
  13. Thanks oldlady so much but my country is egypt. i made too much trials and searches about this material every where but find no thing most of people mentioned using of oil as base for this material but oil is not efficient. am waiting for the recipe you got from the book.
  14. Good point - just to add, For newbies the 108 - 125 final rate segment in the last 200 - 250 degrees will get your cone to bend at or near the published temperature. The cone chart is based on it. Cone 04 - cone 6 - cone 10. The heatwork in the final segment is most significant to maturity and I find the simplified thermodynamic approach is simpler for most to grasp. We often use a simple analogy when students ask about firing to lower cones and adding a hold. At some point it becomes non functional, insignificant and doesn’t work. Our simple analogy is cooking a pizza. Cook it forever at 200 degrees, probably never gonna work. Cook it at 425 for 10 minutes and it’s a masterpiece! (Hopefully) I just don’t want folks to feel this is a cone 6 thing, it’s a maturity and heatwork thing that applies reasonably well throughout. Just my thought though ..... I think I will warm up the oven, pizza for lunch!
  15. Mama is like snot. Unless you thin it a lot its going to clog the gun. You can stick wood ash or iron wash without Magma. Not many here use the stuff-I love the stuff but only in needed applications let us know how it turns out-I suggets thinning it with hot water in a blender before adding to any sporay mix. Not sure why you would use it to spray? unless you mean you are using it in thiose glazes or washes then spraying it?? And if so I thionk you will have zero issues doing so.
  16. Thanks for all the tips! Based on all the info gathered, my next step is to sieve the glaze. Will check back with results!
  17. Tom, for the sake of clarity (for the newer potters on the forum) it would be a good idea to say this would be for a cone 6 firing. Thanks.
  18. Are the botton of the plates glazes or raw?do they have feet or are they flat. More info please is needed
  19. I finally succumbed to the cup on top for my glazes. Gravity helps and none of my old very expensive syphon type automotive guns like glaze nor is glaze like paint. They don’t rust though, no cheap steel parts. Some of my cups have a ball valve so it’s easy to just fill them in standby mode. Kind of spoiled in that way as I just refuse to tolerate the inconvenience of a bad cup setup. Another black hole - also been working on airbrushing underglaze around 1 mm. Magma results should be interesting
  20. I've seen this happen on really thin thrown plates. Are you trimmIng at all?
  21. If anyone ran measured effects of heat work, it would be Orton Sr. He wrote several abstracts for American Ceramic Society, I will nose around and see what I can find. The other source would be Ougland and Brindley from the British Ceramic Society: "Effects of a High Temperature on Kaolinite" I read that abstract, and quoted some of it in my threads. It has since been pulled down, sadly. I have been pricing gradient kilns: and potters gasp at the price of an electric. Keep waiting for a good used one to come along. From my observation pending kiln size: there can be up to 40F difference in a large chamber. Years ago I started mixing my crystalline glazes via PH meter. I raise the PH in cold spots, and lower it in cold spots: works fairly well. I would put conduction up to 2000F, and radiation there after. Edit add: If Edison did not have Telsa: his inventions would have been few. IMOIMO Tom
  22. i have experience in using HVLP and siphon spray guns. you can keep all the complicated HVLP guns, just don't try to take my simple to clean siphon type. EZE makes a good sprayer, their bottles are a four letter word, though.
  23. No enough said, it sounds like an interesting study. We surmise that convection is minor, conduction somewhat contributory and radiation the predominate thermal engine after red heat. Just curious if someone quantified this throughout the firing and related it to core temps is all. We have no effective way to test this in a practical manner. *Seger my unsung hero BTW much like Nikola Tesla* As to gradients, the difference in ware temperature top to bottom is usually significant as well as outside to in, yet quartz inversion happens across a fairly specific temperature so our supposition has always been clay can take a good bit of stress and movement since parts of a body are inverting while other parts are not. I was hoping the study would maybe provide some quantifiable evidence in this respect to expand on the clay can take it theory. As to final leg of the firing, consistent with what we teach so no new revelation from the X-ray analysis is my take. Can you get your hands on the equipment? I have a handful of tests I need to do. thanks! Hey, last random thought R.T. Stull taught at Uof I!
  24. welcome, what country? the label on the jar shows that the material can be piped. that is the most commonly used way of applying the lines. Angelica Pozo, in the USA, wrote a book about tiles and included this technique. i have her recipe in my studio and will find it for you. it is very simple. you have put your question in a section where many members who can help may not see it. could you move it from "forum FAQ and terms of use" to one called "Clay and Glaze Chemistry" so you can get an answer. you never need to start with a cry for help, that is what you always need when you ask a question.
  25. Show us a picture of what you are seeing. best, Pres
  26. Now that the MAGMA product is in my arsenal, I'm thinking different ways to use it. Do you think it would play nice in a HVLP spray gun? I'm thinking about using it to float wood ash or my iron wash and spray a light coat over glazes. You'd certainly want to clean the gun well after each use and getting the mixture to the right consistency would be critical. I'm just wondering if anyone has already tried this. If not, I'll let you know.
  27. Sorry Bill, I broke my two cup rule. Never answer questions until I finish the second cup. As I recall: one study was done in Brazil , one in India for their Government, and one in Germany? All three used gradient kilns with 6-10 chambers and 10-15C variation between chambers. The one in India was testing laterite, and reported an exothermic reaction at 2050F. The study in San Paulo? Actually used bars in various thickness 1/4 to 1/2 in a multi chamber gradient kiln: that studied produced the time of heat absorption and release at 2050F: conduction being the focus as I recall. The one out of Germany was studying local materials, and reported the reaction at 2050F. So 2050F spinel to mullite temp has been confirmed numerous times. U of I (Champaign/Urbana) has numerous studies up on their Ceramic Technology site. I posted a link in one of my ramblings somewhere : stoneware study thread I think. They used X-ray diffraction to analyze heat work and the phase changes in potassium and sodium. At 2190F, sodium and potassium are spent- no longer visible. I cannot confirm this: but I suspect this is where the commonly used 2190F peak with hold firing cycle came from. Orton Sr. Did extensive studies back in 1909-1919 range(?) noted in my Nerds Firing Schedule thread. He proposed the 108F ramp speed for several reasons: primarily to burn off inorganic carbons, secondly for heat work purposes. As you well know, cones are based on Segers work, but Orton did the initial testing on calibrated heat work. did I answer them that time, or do I need a third cup? Check my Stoneware study thread, Nerds Firing Schedule thread, and possibly my Porcelain thread. I have links to studies floating all around. I do know some studies are no longer accessible: Wiley Library has been buying them up and archiving them. Tom
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