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neilestrick

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Everything posted by neilestrick

  1. I think maybe you're working too slowly. It should only take a minute max to sift the plaster into the water, another minute at most to gently hand mix. Then lit it sit for a couple of minutes and then power mix.
  2. No glaze is going to brush well unless it contains a lot of Gerstley Borate or you add the necessary ingredients to make it brushable, namely CMC gum. Typically a gum solution is made with 2 tablespoons of CMC to 1 gallon of water, and the solution is used in place of 1/3-1/2 of the water in the glaze. Since your glaze(s) is already mixed, you don't want to use that solution because there will be way too much water. You could add the CMC directly to the glaze, but it's difficult to get it to mix in well doing it that way. So instead, make up some gum solution that's really thick like snot. Mix 2 tablespoons CMC and 1/4 tsp copper carbonate (preservative) with 1 quart of hot water, let it sit overnight, then blend with a stick blender. If you're using small containers of glaze like pints or quarts, add a spoonful of the snot to the glaze and blend. See how it brushes, and add another spoonful if needed.
  3. I believe that recommendation is to prevent the material from getting into the element grooves. I don't think that switching to another material is necessarily any better in that regard. If you're going to do it, use the material that works the best which would be silica sand, and just be sure not to get any into your elements, and vacuum them out after firing. There is very little shrinkage in a bisque firing, so it's more about even heating/cooling and/or expansion/contraction during the heating/cooling.
  4. I think you'll just have to try it. My gut says 3 kiln is too many, though, and you'll get freezing. How is your kiln constructed? 40 minutes to an hour seems a little long for a typical raku kiln.
  5. @jcwilson Welcome to the forum! Can you please post a picture of the control system for the kiln? Is it digital? Is it manual- does it have a Kiln Sitter? We have a couple of members from your side of the pond, but the majority are in the US and aren't very familiar with the brands of kilns you have there. They all work about the same, though, so if we can see what we're dealing with that will help.
  6. Does it have a 'copy' function like the Genesis, where you can copy the Cone Fire schedule into a custom program?
  7. A waster slab should do the trick, or put some silica sand on the shelf. Make sure you put kiln wash or alumina wax on the waster slab so the tile doesn't stick to it. If you need a cooling ramp it would be during quartz inversion, so from about 1100 to 900, but it's rare that you would need that.
  8. It's odd to have a gap between sections like that. It could very well be the cause of the problem down there, or at least a partial cause. There are ways to fix that with some work on the bricks, but the easy solution would be to lay a thin layer of fiber under the bottom row of bricks, to seal up any gaps. Lay it all the way around, full width of the bricks, and set the ring on it. It'll compress where the bricks fit tight, and fill gaps where they're not. I would not try to mortar the gap. Smear some mortar in the floor cracks. Not a big deal. Did you have a shelf at the bottom? You need one down there, up on 1/2" posts. Otherwise the bottom will definitely run cold. When you load the kiln, at the bottom you should put low mass pots like bowls or tall pieces, pack the middle section really tight, put whatever's left at the top, preferably semi-tight. Also check your elements with a meter to see if their resistance is correct. Could be the bottom is worn more than the others, which is not uncommon.
  9. There are always exceptions to the rule, but I would not recommend trying that again. Glad it worked out for you!
  10. Those shrinkage rates are more than close enough for what you're doing, and those numbers are way too precise. There will always be slight differences in shrinkage depending on the accuracy of the firing, the thickness of the pieces, etc, so for them to give a number that precise is totally unnecessary. They basically have the same shrinkage rate.
  11. What type of kiln is it? If it has a door, just pull the obvara and then close it up and finish the raku pieces. Otherwise I think you'd probably be fine just firing up to raku temps and pulling the raku pieces first while the obvara cools a bit. It's not an exact temperature anyway, since the pieces cools some between the kiln and the bucket, and the last piece is always a lot cooler than the first.
  12. Unless you make it considerably thicker, porcelain is going to warp with a form like that.
  13. On a regular manual kiln the drop and hold is near impossible. On this kiln not possible at all. It's the realm of digital controllers.
  14. These kilns fire fast. Probably not a stuck relay for that model based on your description. There has been a lot of discussion about them here on the forum. HERE is a great thread that will give you lots of info.
  15. Computer fans work great for this application. There's already a grill in place on the box, so measure that and get a fan that fits. This is a small enough box that the output of the fan won't matter. Amazon carries a bunch for very low prices.
  16. Is there a fan on the outside of the case that we can't see in the photos? Definitely need a fan to keep the SSR cool.
  17. Not everyone wants to or is able to throw dinner plates on the wheel. I slab build my plates, and it is much faster than throwing and I don't have problems with humping in the middle. @chris123 I think the issue is either with glaze tension as mentioned above, or it could be from uneven heating/cooling between the edges and the center or the top and bottom. 1. Does it happen with all of your glazes or just one? 2. What size kiln do you have, and what firing schedule are you using?
  18. @Retxy are you digging your own clay or are you buying raw materials (or both)?
  19. I'd remove the control panel and take off the insulating baffle and see if it's dry inside. If it's still damp, let it sit open for a day or two indoors so the electronics can dry out completely. You do not have to have the elements connected to the kiln to test the control box, and should not if the bricks are still wet. You will need to have the thermocouple connected if you want the controller to do anything besides read FAIL.
  20. I'd replace the element. Even ground down there's not going to be much you can clamp onto there. Better to have a good connection.
  21. I'm afraid I kind of agree with BlueBird. If it has half dollar size holes in it due to corrosion, the rest of it is probably not structurally sound. The non-pugmill option is to simply not wedge and not recycle. Most clay bodies are good to go for throwing right out of the bag. I switched to slab building about a year ago after 30 years of throwing, due to bad arthritis in my hands. Gotta say I don't really miss throwing. I'm happy to still be working with clay, and the challenges and possibilities of working with new techniques have me more excited about ceramics than I have been in a long time.
  22. Just a thought, but depending on how much space there is around the auger and how this is constructed, you may be able to weld in sheet of steel as a liner.
  23. CI made the larger wheels like the MP and HP main structure from plastic, and coated the wheel heads. The Clay Boss has more metal, but the head is still coated. I wouldn't use heat.
  24. Results will be the same, but they may or may not use the same elements for each wiring setup. By the math if you wire the single phase as three phase it's going to pull 18.5 amps, not 10, so I don't know what's going on there. Very different wire size requirements for those amperages, too. It doesn't appear to be as simple as just picking one or the other.
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