neilestrick

SRML wire is perfectly fine for use in kilns. I've used it in dozens upon dozens of kiln for the last 20 years without problem, including Gare/Evenheat kilns just like this. It is very common in kilns.

If you wire the way they currently have it, it'll need to be able to handle the entire 30 amps that the kiln draws, so at least 10ga. 8ga would be better so you're not maxing it out, but it'll get kind of bulky in there. The silicone coated wire would be less bulky than the SRML. The other option would be to wire each switch individually from the Sitter instead of daisy-chaining them, and use 12 ga wire. Any connectors on the ends of the wires should be high temp connectors.

SRML wire is also commonly used in kilns, and is less expensive. https://www.wireandcableyourway.com/12-awg-srml-sewf-2-silicone-rubber-wire-high-temperature-motor-lead-wire-ul3231-3070

Describe the 'kiln alarm'. I've never heard of these kilns having any sort of alarm. Are you sure it's not a relay or switch that's chattering?

So it is a 3 wire system, no neutral. The 6-15 receptacle is for adding on another ring, which was common on a lot of the old kilns. I would just unhook that if you don't have the ring. Is the wiring really dirty, or is it the old waxy cloth wrapped wiring?

Thank you!

Thanks for all the info! I've been doing a lot of underglaze transfers over the last couple of months, and I tried using the newsprint I use to wrap pots when I sell them, and I was not happy with the results. The underglaze is much more likely to flake off when it dries, and the wrinkling is a big issue. I'm doing large patterns, not line work, so there's a lot of underglaze on the paper and it wrinkles up a lot. I've settled on half-raw rice paper, printed on the raw side. It holds the underglaze well, releases very quickly, and doesn't wrinkle much at all. I've just been buying it off Amazon, about 29 cents per sheet. I've been using adhesive vinyl cut on my Cricut to make the screens, with Speedball Screen Filler, and it has worked very well. This is a shot of the vinyl being removed from the screen once the filler has dried:

If the controller is overheating then you don't have adequate ventilation in the kiln room. Set up a fan to move some fresh air into the space.

In looking at other examples of that glaze, it appears that it does like to go metallic. The lack of color may be due to thickness issues. I'd run a few test tiles ranging from 2-5 coats of glaze and see which one gives the best color. If they all stay metallic then it's probably a temperature issue.

So it's actually a cone 8 clay. Not as tight as I'd like at cone 5, too tight at cone 10 (for a stoneware body).

I should have specified that I was referring to kilns, not other appliances, but I get what you're saying. And the serial plate doesn't specify 120/240.

Yes, pics inside the kiln. I've never seen this model of kiln with a neutral, nor have I seen a 3 wire plug with a neutral and no ground, but hey that doesn't mean they don't exist. An ungrounded kiln would not be safe, though. Even though the 10-50 is technically 2 hots and a neutral, ungrounded, they are probably using it as a 2 hots and ground. No guarantee that cord is the original. Post some pics of inside the control box and that will clear everything up.

Any time you add a plug into the system it's another weak point, so the fewer the better. Not using an extension cord is most likely a physical safety thing rather than an electrical thing. A long cord is far more likely to be tripped over, which could cause the kiln to be pulled off the stand while hot. An RV isn't going to tip over and start a fire if you trip on the cord. A 6 foot long, 3 wire, 50 amp oven cord would work fine. If you get a 4 wire that matches your outlet, just don't use the neutral wire.

That's an odd ruling, because that would mean a kiln would not be hooked up according to manufacturer's recommendations, and in the case of a UL listed kiln it would require changing the plug and possibly negating the UL Listing. @Bill Kielb have you ever heard of that rule? Ground wire should be attached to the appropriate ground terminal all the way through from the breaker box to the kiln box. The neutral should not be used at all. Adapters and extension cords are not safe for use on kilns. I wouldn't fire any pots until you test it, but I wouldn't run a test until you measure the element resistance.

Have you tried programming a different user number? There are usually 6 user numbers you can store, so try a different one and see if you have the same problem. Have you tried turning it off and back on? Not to be silly, but that often works. You could also try a reset in the system, which is under the Options menu. That will wipe out any configuration you've done so you may have to redo things if you've done anything with thermocouple offsets and such. HERE is a link to the manual if you don't have one.

Code requires that kilns be on a breaker that is 25% greater than the draw but no more than 50% greater, so your 30 amp kiln needs to be on a 40 amp breaker. The Sitter can handle up to 45 amps. The 14-50 plug is a 4 wire plug- 2 hots, neutral, ground. Your kiln is a 3 wire setup- 2 hots, ground- so you'll have an extra terminal in there that you do not need. I would change out your outlet to a 6-50, which is a 3 wire, and get a new 50 amp power cord with a 6-50 plug. It's always nice to have an oversized power cord. There's no good reason to use that old cord with a new plug. What size wiring is going from the breaker to the outlet? It needs to be sized to handle at least the amperage rating of the breaker, so if it's a 40 amp breaker you need at least 8 gauge wire. Anything smaller than that will need to be changed. Anything larger than that is just fine. Are there 3 or 4 wires going to the outlet? If there are 4, cap off the neutral because you don't need it, or if you need to run new wire then just run 2 hots and a ground. I'm not a big fan of having unused terminals in outlets and plugs because it just makes things more complicated than it needs to be when doing repairs. I would only change the elements if they need it. Unplug the kiln, turn on the Sitter and all the switches, and measure the resistance (ohms on the meter, little horseshoe symbol) at the two hot prongs on the power cord. It should be around 8 ohms- 240 (volts) divided by 30 (amps). You can also check each element by turning on each switch one at a time. Each element should measure around 32 ohms.

Small closets that are just big enough for the kiln are not a good solution IMO. For one, there's not enough space to store shelves and posts and such. Second, they can be difficult to load and repair due to having limited space to move about. Third, they require really good ventilation, meaning an overhead vent pulling heat out, and a good source of fresh air coming in. It's really easy to overheat a digital kiln in a small space, because you're not only dealing with the heat directly from the kiln, but also the reflected heat from the walls. The controller will shut down if it gets too hot, so there has to be a lot of air moving past the kiln in order to keep the controller cool.

The kiln should be vented for both fumes and heat. That could mean an overhead hood, a ceiling vent that's sized for the kiln and room size, or either of those in combination with a downdraft vent.

Chances are the clay will be too tight after cone 6 to survive the shock of raku firing afterward. It will also be too tight to carbon trap the way it normally would in raku. And the liner glaze would likely craze from the thermal shock, in which case you'd still have a leaky pot since the clay wouldn't be fired to maturity. And applying the raku glazes will be a bear since the pot won't be absorbent after cone 6. Unfortunately you just have to accept raku for what it is- not water tight.

The first glaze should be dry to the touch (which could mean anywhere from a few minutes to a couple of hours), but not totally dry. Different glazes dry at different rates, so as you use your glazes more you'll learn when the best time is to do the second glaze.

The kiln will take 6-12 hours to fire up, then another 12-24 hours to cool depending on how big the kiln is and how much work is in it. So at best you have about 18 hours where it will be hot and could be a danger to the kids. Plus the vent will be running and that can be loud. So no, it's not ideal. That said, I work on a lot of kilns that live in the classroom and they seem to make it work just fine- by firing on days when they don't have a full schedule, or timing the firing so that it's hottest when the classroom isn't being used and it can cool overnight. Ideally it would be best to have it in its own room, but I get that that isn't always possible. By only working at low fire temps you can shorten both the firing time and the cooling time. At the very least you should invest in a safety screen like THIS. They're usually available through Blick and School Specialty, too. Another option to keep the kids away is to build a chain-link fence around it. Dog kennel panels work well. How is the kiln vented?

The floor is shot, but the lid doesn't look like it's going to last much longer, either. The bad news is that new lid and floor slabs cost about $300 each, plus shipping by freight, so it may or may not be worth that for such an old kiln. Also, if the outer steel band that goes around the floor slab also goes around the bottom section of the kiln walls, it can be a real bear to change out the slab, and may require some sanding of the bricks to get a new slab to fit. Duncan no longer makes kilns so you'll have to get a slab from another kiln company and it may not fit perfectly. Also, the new slabs will be brick, not fiber, so they'll insulate differently and the peak temp rating of the kiln may be lower. Post a pic of the serial plate so we can see what the wattage of the kiln is.

Leave the TC offset alone and just program it to a higher cone.

Hi @MD pottery, welcome to the forum! Is this a fiber floor or a brick floor? Post pics if you can.

If you can't figure out the timer relay situation or can't get parts, you can just add one more 15 amp infinite switch, do away with all the relays, and wire each element set to one of the switches. If it were me, I'd go ahead and replace the old switch, too, so you're starting fresh with matching switches. Any 240 volt, 15 amp infinite switch kit will work. I like Robert Shaw brand. Make sure it includes the knob, because many don't.