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neilestrick

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Posts posted by neilestrick

  1. As Dick said, the logs show the status every 30 seconds. The set point is the temperature the kiln is trying to achieve. It is always changing unless it's in a hold, and typically the thermocouple readings are a couple of degrees behind the set point. The logs are most handy when looking at kilns with multiple zones, as you can then see if a zone is lagging behind the others and/or causing problems.

  2. 1 hour ago, Denice said:

    I have two kilns with the Bartlett Genesis controllers,  I need to sign up and pay a monthly fee to access more information from my firings.  Are you a member?  Perhaps you need to be to access your info.  I am not very computer literate so I haven't joined.     Denice

    You do not need to pay for the upgrade in order to be able to download firing logs. The upgrade is to get alerts, and it's worth it IMO.

  3. It takes very little reduction to keep a kiln in reduction during cooling. Small pieces of wood are an easy way to do it in a kiln that's already got bricks that are glazed up from soda or salt, but I wouldn't do it in a straight gas kiln because it'll make a mess of the fireboxes at cone 10. The other option is to seal off the burner ports and just have a small pilot burner going though a small hole.

    If you want the clay to be black from reduction cooling, use a clay body that has 4.5% iron in it. Letting in small amount so oxygen at various points in the cooling will cause flashing.

  4. I would try substituting some or all of the ball clay with kaolin for starters, and adding a little bentonite. If that doesn't do the trick, try washing the ash at least a couple of times. Unwashed wood wash has a lot of soluble material in it that affects flocculation. Washing will probably affect the melt a bit, so it may require a recipe adjustment. FYI, unwashed ash is very caustic, so it's a good idea to wear gloves while dipping and definitely wear a respirator when spraying. Washing it will make it less caustic, so that's a bonus.

  5. 15 hours ago, Russ said:

    One possibility . .... It could be the breaker that is wearing out. Breakers over time become overly sensitive especially if theyre run close to the tripping point for a long time. An electrician could figure that out for you.

    If the breaker is blowing immediately upon starting the kiln then it's most likely a short, probably from a connection that has fried out or come loose, causing a wire to contact metal. Or possibly from a relay that fried hard. If the breaker is blowing after the kiln runs for a bit, then it's probably a worn breaker.

  6. I agree, the underglaze looks kinda thick. What brand of underglazes are you using? Most will give you a good solid color of you thin them down a little bit and apply 3-4 thin coats, brushing each coat in the opposite direction of the previous coat.

    I find that clear glaze covers better when dipping if you apply the underglaze before bisque firing, so that the binders burn out in the bisque, leaving the surface more porous for the glaze application.

  7. As for cone 7 going down, the hold at the peak is going to add a little bit of heatwork, as is doing a slow cool from the peak. If you don't need the hold at the top for glaze reasons then don't do it. If you want to do a slow cool for crystal development in your glazes, drop to 1050C at full speed, then do the slow cool. It would be a good idea to do a firing with just a few shelves in the kiln and cones at two levels, Medium speed to cone 6, and see what the cones show. From there you can do a thermocouple offset or a cone offset to dial it in so it's firing accurately. After that you can deal with the glaze issue.

  8. 5 hours ago, oldlady said:

    well, i thought i could get several 21 inch whole thermal lite shelves but at $337 each, my last sale would only buy 3 of them.  a full kilnload runs about 8-9 shelves, the very heavy solid  shelves i have had for 30 years or so.  you can understand my dilemma.

    so we discussed cordelite ones.  they weigh only 14 pounds for a 21 inch whole shelf and cost $83 each.  i have no experience with them.   do they warp? 

    any opinions?  my age and the prices of the work i make would make a bookeeper laugh at the question.  i only care about the weight and being able to continue to work. 

    I've used CoreLite shelves for years, and I really like them. They stay flat much longer than standard shelves, and are as light as Advancers/Thermal-Lites. I think half shelves will last longer than full shelves, though, so if you don't need full shelves don't get them.

  9. Set the gas for the rate of climb you want, set the air for the degree of reduction, and set the damper so you have back pressure out both spy holes. One will have a lot of pressure, the other just a touch. Each time you adjust one of these the other two may need adjustment as well. There is such a thing as too much gas and air, and generally the damper will only need very small adjustments. Keep notes as you go.

  10. Gum is added specifically to make them brush nicely and to harden the surface so that added layers don't pick up the previous layer. Part of what makes that work is that you have a higher water content in the glaze, plus the gum itself makes the glaze slimy and slows down drying. That is definitely a problem when it comes to spraying, so I would first see if any of the glazes you like to use are available in dry form so that you can mix them without any gum. If not, then I think you're just going to have to spray them in thinner layers, letting each layer dry between applications. Or you can start mixing your own glazes.

  11. 37 minutes ago, fergusonjeff said:

    There might be a little more to the calculation than you accounted for in just the economics.  I have a mix of both corelite and advancers for both my large electric and my gas kilns.  I had lots of issues with warped shelves and the corelite were much better.  I was still getting a lot of warping in my slab plates with the core-lite shelves.  The advancers completely fixed the warping.  I don;t think it is only because they are very flat.  I think they heat the ware a little more and allow slab plates to settle perfectly flat on the perfectly flat shelves.  I use the advancers for slab plates and the core-lites for bowls and mugs.  I recommend a mix of advancers and core-lites for a compromise in firing properties and economics.

    I've never had that problem, even with the really thick CoreLites, but I can totally see how it may be an issue.

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