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neilestrick

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Everything posted by neilestrick

  1. There should be an adjustment to the controls in either the pedal or the controller that will stop it, or a mechanical adjustment within the pedal. I'm not familiar with that pedal so I can't give any details, but someone will chime in here that has one.
  2. You can burn it in a metal can or grill, but you'll find that you have to burn a lot of anything to make a worthwhile amount of ash. Ash weighs very little, so making enough for a recipe like Nuka that uses 30% will take a whole lot of rice husks. You'll need several pounds of ash to make a 5 gallon bucket of glaze.
  3. Most coatings do not bond well to old bricks, especially if there are already at the point of flaking, so I would talk to the ITC folks before doing anything. I don't think the heat reflection should be significant enough to cause any problems, especially since the lid is a major source of heat loss to begin with, and ITC isn't as glorious as some make it out to be. If you didn't thin out the cement before applying it, it will definitely flake. It needs to go on very thin when you coat the lid. If your floor slab is in good condition then you could swap it with the lid. The simplest solution is to put a shelf at the very top of the load to block any crumbs. Keep a look out for an old used cheap kiln that has a good slab you can use. A new slab will cost you $400-600 with shipping, so finding a used one is a good way to go.
  4. Air pockets of any size will not cause explosions. Air doesn't increase in volume enough to blow apart clay. However with a closed piece, whether completely closed or with a pin hole, it can take a really long time for it to dry completely because there's little to no air flow on the inside. It can be bone dry on the outside and still leather hard on the interior. So you need to dry it for a long time and do a good long preheat in the kiln to make sure it's totally dry before taking the temp up. Otherwise you risk steam explosions. This is why people think you can't fire a closed form. They think it's dry (but it's not), it blows up, must be because it was closed! Nope. You can fire a totally closed hollow piece just fine, it just takes forever to dry out. The pin hole will relieve air pressure building up in the piece as it shrinks during drying and firing, which can cause distortion in clay bodies like porcelain, which soften up during glaze firing. I've seen porcelain pots inflate slightly during glaze firing due to the air pressure.
  5. To some degree, but not as much as you would expect. In a typical firing it's really negligible. On the Genesis you can download firing data that has a data sample every 30 seconds. I've looked at both SSR and mechanical relay firings on my kilns and while the SSR firings tend to follow the traveling set point almost exactly, rarely deviating and never more than 1 degree, the mechanical relays tend to stay within 3-4 degrees, which is plenty tight for your typical pottery firing. I've also checked firing costs on both, and it only fluctuates by a few cents. If temperature control was a real issue with the mechanical relays, I would expect to see the kiln working harder to keep up with the set point and also working harder to maintain evenness. But the firing cost doesn't show any significant difference. That said, those were in typical firings. If you were doing firings that required greater control, like say crystalline glaze schedules which have lots of holds and ups and downs, I would expect the tighter control of the SSR to be able to respond and make those changes more quickly and efficiently. This is definitely worth it if you build your own system. If you're paying for the upgrade from the factory you have to math out the cost benefit. If you use the kiln a lot and take care of it, you can get 2000 firings out of a kiln, which means about 10 relay changes over the lifespan. If you get your relays online you'll pay about $20 per relay with shipping, so the total cost comes out to about $600 over the life of the kiln. So if the SSR upgrade cost is less than that then you're coming out ahead. Factor in time spent on repairs and it's even better, although it only takes about 5 minutes to change out the relays. If you're a casual kiln user who's only going to do 500 firings over 20 years, an SSR upgrade probably won't pay off. You could just replace the mechanical relays every 150 firings and never really worry about them failing. Above all else, the SSR system is REALLY COOL and everyone should have one.
  6. The very top and very bottom elements run hotter to compensate for heat loss out the lid and floor. What Bill said. I't probably a wiring problem. The feeder wires go from the terminal strip to the ends of one element, and a short wire jumps from there to the next element.
  7. Your kiln has 3 rings/sections, and each ring has two elements. Each element loops twice, so 4 rows of elements. Each ring of the kiln is connected to a relay, so 3 relays. The relays are what you hear clicking when the kiln is firing. They're just switches that send power to the elements. Because your kiln has both elements dead in one ring, you likely have a dead relay. If the problem was an element, then we would probably see only one dead element, because it's very rare for two elements to fail at the same time. Unplug the kiln and open up the control box and inspect for any obvious fried wiring connections. Then open up the panel in the control box to get to the internal wiring and relays. Again, check for any obvious fried connections. If everything looks good, then the relay for that section is likely the culprit. Because all 3 relays click at the same time, if one has died to to age, then the other two are probably close to dying as well, so you should replace all 3. You can either get them from Skutt, or source them yourself on the internet for a lower price. Just search for the part number on the relay.
  8. @Velk In your controller: Main Menu - Configuration - Number of Zones Make sure it's set to 1 zone.
  9. I briefly looked into it as well. Lava has a range from 700C to 1300C, the bottom of the Earth's crust is 1000C, and the core is 5,200C, and minerals melt as all sorts of different ranges, so I'm not sure there is a single temperature that is the magic number for the planet.
  10. I think that in the earlier days of cone 5/6 work this was true to some extent, but not any more. The development and marketing of cone 6 glazes prior to 7-8 years ago was very much geared toward making imitations of classic cone 10 glazes. I think this approach was a bad way to do it, though, because it classified cone 6 work as something that was less desirable. It was the poor man's cone 10. It was something you were forced to to if you didn't have access to a gas kiln- the realm of hobby potters, not professionals. However in the last 7-8 years, things have changed considerably. Now cone 6 work very much stands on its own, and is likely more common than cone 10 not just among hobbyists but also professionals. Plus you can't just drop some boron into a cone 10 glaze and have a cone 6 version. Most all classic cone 10 glazes were fired in reduction, and reducing the melt is only part of the process. Mimicking the look of reduction requires additional changes in chemistry and often makes it impossible to make an equivalent cone 6 version, otherwise we'd have cone 6 shino and tenmoku glazes that are indistinguishable from their cone 10 versions, which is not the case. Since the glaze manufacturers embraced cone 6 glaze chemistry as its own thing and started to explore what could really be done with that chemistry, we have seen some really amazing glazes come to market. The variety of cone 6 glazes now dwarfs what has been been done in cone 10 work. Personally, when I made the switch from cone 10 to cone 6, I approached it from the standpoint of modifying my tried and true cone 10 glazes. I quickly realized that I was taking the wrong approach. I find cone 6 formulation the be very different than cone 10 formulation, mostly because materials like frits are very powerful compared to most of the standard materials we use at cone 10. It still blows my mind that we can make glossy glazes with 24% EPK in the recipe. Plus the color palette that we can do at cone 6 is huge, and easier since we can use stains that aren't stable at higher temps. I actually find cone 6 formulation to be easier than cone 10. Why cone 6? No idea. However if we really wanted to conserve energy and extend the life of our kilns, we would be firing at cone 3. We can still make vitrified bodies using feldspar at cone 3, and element life would be fabulous, probably 200 firings instead of 150. If I was working alone and didn't have a community studio, I would develop a cone 3 porcelain and glazes. There's no reason not to. I think we're probably stuck at cone 6 for a good long time, though, because we are at the mercy of the commercial suppliers, and they've got a good thing going at cone 6. I hope that we'll see more schools switch from cone 10 reduction to cone 6, because that is what most of their students are going to be doing when they graduate. They could still use their gas kilns, but cut their firing costs in half. Sorry for the long post. I spent my first 16 years in pottery working at cone 10, and the last 14 years have been at cone 6, so I have a lot of opinions on the subject. I could write pages and pages about it! Switching to cone 6 electric was the best thing I've done for both my business and the development of my work, but I totally get why cone 10 gas firing is better for some people.
  11. Thanks! I built both of them. The big box came from an L&L DaVinci I had before the current eQuad 2827. I gutted it and rebuilt it as a 3 zone SSR system. The little box was from an old Orton wall mount system. I changed out the controller and added the SSR system. My primary reason for the SSR's is to see how long it extends element life. There is a lot of documentation saying that element life is better with SSR's, but I have yet to find anything that says how much better. 5%? 10%? More? The bad thing is that it'll take another year or two of firings before I'll know!
  12. I wouldn't expect the cooling to be a problem with little bowls. Chances are they were already cracked or stressed before the firing. Can you post a picture of the cracks?
  13. Definitely a possibility, but I would expect to see more globs/thicker areas where lines come together.
  14. In a typical firing, yes, it gets to temp and then turns off. Some people will program the kiln to cool at a specific rate, though, which we refer to as 'slow cooling'. Slow cooling can be used to change how glazes look, because more crystal growth happens as the cooling is slowed. This can result in better color development or changes in the surface of the glaze (matte, shiny, etc.). Another reason for a controlled cooling cycle is to achieve the same results from different kilns. For instance, I have 3 kilns- a 10 cubic foot model, a 4 cubic foot model, and a -1 cubic foot test kiln. They all cool at very different rates, and some of my glazes will look different depending on which kiln they're fired in. By using the same programmed cooling rate in all 3 kilns, I get the same results regardless of which kiln I use.
  15. Given the consistency of the raised lines, my guess is that the design was carved into plaster, and then that was used to stamp out this piece. The color was then applied.
  16. Often I'll just work in silence. I don't get that very often in the studio so it's kinda nice. But if I need some sound I'll turn on a Pandora station or a mix on my laptop.
  17. If you know it's firing hot, then it would be worth your time to run an empty load with cones and get it dialed in so you don't have to watch it. It may take a couple of firings, but it'll be worth it in the long run to be able to trust your controller.
  18. @Dana Stripe Welcome to the forum! Thank you for sharing your build. It's a nice setup, excellent craftsmanship! This tends to happens when the kiln room is not adequately vented. In a properly vented room it should never happen. In the case of your setup, the fans are a great way to go because you don't have a layer of insulation between the kiln and the box from what I can see (the standoff will help though). I've got an SSR panel that sits next to the kiln (L&L DaVinci panel), and I'm amazed at how hot the surface facing the kiln gets even though it's 18" away. With a single fan in the bottom of the box (which is about 4 times the size of yours) the controller never gets above 105F. I've also got a little controller box with a single SSR that I use for my baby kiln, but because it's wall mounted I just put a heat sink on the box, no fan.
  19. The control can make changes to the final temp depending on the speed of the firing, to make sure the proper heatwork is achieved. It also depends on how the controller is set up- whether it shuts off the kiln when the average of the sections reaches the set point, or if it turns of when any one section reaches the set point. And sometimes it just overshoots a little bit because the elements take a little time to stop radiating.
  20. Testing the SSR directly while under load is darn near impossible in a Skutt, and ceratinly wouldn't be safe with the insulating baffle loose. But you can test it at the terminal strip on the element side of the baffle, you'll just be a few inches down wire from the relay itself. Is this is the same transformer it has always had, or did you swap it out during all this troubleshooting? I wouldn't expect a transformer to suddenly start being the problem unless it actually died, which is really rare. The 16.5 volts was at the relay, correct? Do we know what the voltage is at the transformer output/control board input? Sorry if you posted that already, I couldn't find it. If the control board input is normal (24V) but the output is high (16.5V) then that would point to a control board issue, which could also explain a lot of the other issues.
  21. Are you running the wheel counter-clockwise? Some of mine run really loud when in reverse. In general they do tend to quiet down after they have a few hours on them, but using a commutator stick on the motor will quiet them down faster (assuming they're still using the same type of motors I have on mine). Post a video of the wheel so we can hear it. Removing the wheelhead and turning it 180 degrees will usually make it sit more solid. Check that there's not a big glob of anti-sieze lube in there making it sit uneven.
  22. Interesting. We see quick error like that that on multi zone kilns if the relays and thermocouples aren't set together properly, like if the zone 1 TC is paired with the zone 2 relay. But on a single zone it would only happen if the TC system is backwards or it's not getting any power. Just to rule out any programming issues, what firing program is she using when this happens? It could be that if she's putting in a rate of 500F/hr or something very fast like that, that the kiln simply can't keep up with the traveling set point at the start of the firing since it takes a little time for things to get hot. Does it happen with a rate of 9999? At 9999 the controller doesn't follow a traveling set point, it just goes as fast as it can and is happy with whatever speed that is.
  23. You're correct, the little controller only has one TC input. Sorry for the dumb questions, I'm not familiar with the specifics of that model. If it errors very quickly, it's usually because it's not getting any power at all, or something along the thermocouple system is installed backwards and as the temp in the kiln rises the controller reads it as going down and it reaches the 50 degrees difference very quickly.
  24. How hot is it getting before it errors? Also double check that the controller is set for one thermocouple.
  25. Error D is a difference between the thermocouples. This is a Glazetech kiln with only one thermocouple, correct? If that's the case, then the controller is probably set with the wrong number of thermocouples. Still don't know why you're getting 42 volts out of the SSR when it's open. I just tested mine and they trickle 4 volts.
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