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  2. I single-fire PC all the time--always get great results (same with Coyote). I usually program for slow-glaze. Just FYI, there is a Facebook Group for these glazes-often helpful & lots of photos of people's work. https://www.facebook.com/groups/potterschoiceex/
  3. All right, will definitely take into consideration. Im probably going to try out three different clays now, just because I am in the market for new clay and do not want to purchase 2,000lbs of clay that doesn't work well with some of my other glazes. Thanks for your help though, I have not had to take absorption into account for years (and honestly forgot to check it) Have a good day!
  4. I do not. I throw porcelain and prefer several but find it is a personal preference thing. Just wanted to get you thinking about absorption as well as trends in glaze fit.(not necessarily related) Typical, not always but typically functional potters target 0.5% and will accept 1%. When I learned - 3% leaks on your grandmothers antique piano, 2% probably, 1% maybe. Manufactures would love to sell 3% as being good enough That would be absorption rate, not shrinkage though.
  5. Yesterday
  6. 2% or under is fine, over 2% and you risk weeping, microwave issues, mold and mildew. What I hate is that the bodies I've tried that are closer to 1% are more finicky in the ole kiln. Bloatier when fired a little hot.
  7. Do you have any recommendations? I only really have Standard Clay near me. Also, most the mid-fire clays seem to be somewhere within the 1.25% to 2% shrinkage rate.
  8. It is more common to match you glaze to your claybody than the other way around so eventually when you settle on a body you may need to get some matching glazes. FYI - We rarely use any body that is not less than 1% absorption at our working cone temp. I am guessing many of the folks here are 1% or less as well. Just a note, porcelain bodies sometimes are harder to fit in that they are generally lower COE so glazes that once were great on stoneware can tend towards crazing on porcelain bodies.
  9. Hopefully you were able to watch them do it so next time it should be easy. Since the orifice fits over the tubing and into the pilot assembly it must have fallen out when they disassembled it. No other possible way to remove it. Good that it’s fixed. If not here is one of many you tube videos that show what it looks like with no orifice.
  10. sounds like problem fixed when orfice was reinstalled after falling out.
  11. It probably works for me because I seldom (never) do slip cast objects and do mostly press molding with my plaster casts, I’m only interested in the quality of the mold surface and if the object releases from the mold, dryings not an issue and so far I’ve never had issues attaching parts or with the firings because of the oil. I guess I’ve used it for years because it good on the skin and was handy one time when I needed something not knowing any better, I’ll have to try the soap.
  12. Did the Parian stick to the kiln shelf?
  13. That's a good clay if you like the feel and look of a buff. I prefer the #630 because it doesn't have grog. It's feels fairly smooth, but fireclay gives it enough tooth to be quite forgiving. I also prefer the color of the #630. Try them both!
  14. I wasn't there, but two techs from our gas supplier showed up this morning, and Wendy showed them the kiln. Not something they deal with everyday, so they were very interested in it. They observed that the pilot was a "lazy flame," took the assembly apart and noted that it did not appear to have a gas orifice. They called Olympic to find out if it was supposed to have one and to get the specs, then one of them went looking for one in their truck. Meanwhile the other tech looked around on the sheet metal under the kiln and found the one that had somehow fallen out. They installed the orifice in the pilot assembly, and it works! And we don't have to tape the red button down to keep it running, either.... They did recommend some maintenance on the whole pilot bar assembly.... we have a problem with the bar burners getting "coked" up with carbon deposits later in a firing (when the main burners are turned up), which I think might be due to gas density effects changing the mix ratio as the propane tank ices up, and thus the supplied gas is colder.... We should probably get a larger tank or a dual tank set-up to reduce the freeze up.
  15. I was thinking of trying Standard 553 Buff clay- C/4-6 Good clay body for production work. Contains fire clay and fine grog. Cone 6 Shrinkage 10.5% Absorption 1.25% Do you think this would be better?
  16. This is just a wild guess but it could be a further variation of Jason Hooper's Val Cushing Pam Matte glaze (with / without copper plus iron). Looks like it's overfired, the VC glaze is super sensitive to firing temp, over cone 5 and it runs.
  17. It may work, but like Min said it'll be trial and error. If you have access to Standard clays, and you want a good stoneware body, I recommend #630, #112, and #211. If you want porcelain, then #365.
  18. Agree with Neil, as the crazing is so severe I wouldn't try the silica fix. It probably will fit a different claybody but it will be trial and error. If you are making functional pots I would ask your supplier for recommendations for a body that has less than 2% absorption and doesn't require low expansion glazes. Going forward, trying out new glaze / clay on test tiles before using on actual pots can save some aggravation. If you are firing to cone 6 then get a clay that matures at cone 6, not cone 9 like the Standard 101 Buff.
  19. Do you think I could fix it with a different clay body? I am looking to switch my clay up, and this may just be the time to do it.
  20. I agree. Spiders love burners. If that doesn't work, those little pilots are cheap and easy to replace.
  21. As crazed as it is, by the time you add enough silica and kaolin to solve the crazing there's a good chance it will affect the melt. It may be easier to mix your own white glaze that you know works.
  22. Very crazed, you will need to adjust the glaze fit some way. Normal for gloss when ya don’t know what is in it you can try to add 1.25:1 silica to clay until it stops crazing. so in parts 1.25 silica : 1 clay 2.5 silica : 2 clay and so on ....
  23. Clean out left side pilot orifice, it’s very tiny. Next time If you have to test simply use your manual light and tape it down trick. That way you only need to unscrew each thermo couple and screw it into the other valve. (No valve moving or piping moving) The picture you originally sent looked yellow and flashed anyway so it seems likely a dirty pilot orifice. Take that side assembly off and clean it out thoroughly there is probably a spider web in there. Don’t forget the orifice is at the end of the tube, clear it with something soft and blow backwards through it, also make sure to clean everything as often spiders will build a web in the assembly itself just after the orifice. See below, everything comes apart and can usually be cleaned in a few minutes.
  24. As if using Stoner as a name for your business isn't recommendation enough. https://www.stonermolding.com/
  25. Update: Swapping thermcouples sounds simple but they have different lead lengths, so the TC from the left side would not work on the right side. Leaving the TC's in place and just swapping them at the valves would require swapping the pilot system gas plumbing at the valves as well.... with already formed tubing cut to length, that would be a lot of work. So we got a new thermocouple, and got that installed (see my other thread on removing the old TC). Started up the left-side pilot system and it was immediately obvious that the pilot flame on the TC was crap. Adjusting the needle valve on the gas TC pilot gas supply offered no improvement. Still had to tape the red button down to keep the pilot burning, but gas was flowing through the valve, so we started the pilot system on the left side (much better pilot flame on that side), and then lit all six main burners to "candle" the kiln for a bit to try to dry things out. Everything was looking good, except for the crappy pilot flame on the left-side TC, but the kiln was running, so we started the firing. We check on it every 15 minutes, and on one of those checks after about two hours, we found the kiln had died. We tried to re-light it, but gas would not flow through the first BASO valve anymore. Wendy took apart the gas supply to the left side TC pilot flame, blew everything out with compressed air to clean it all up, put it back together, but no joy -- the pilot flame was still all yellow, no blue.... So either there is some sort of problem with that pilot "burner" still, or the problem is within the BASO valve -- not supplying the right gas pressure or something. We are still having to tape the red button down to keep the pilot flame burning. Our next step is to get a tech from our gas supplier out to take a look to see if they have any insight (a delivery truck driver from the company was filling a propane tank at our house when we tried firing the kiln last week, and he offered some helpful suggestions then). The kiln is still loaded with "unfired" wares (it only reached about 700F before quitting -- we fire to Cone 10).
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