Dick White

Your burgundy glaze is likely a chrome-tin red. Grey or green is unavoidable for a chrome-tin in reduction. If you still want a red in reduction, you have to go for a copper red.

The flame should be drawn in only in the bottom holes. There is too much leakage around other areas of the kiln (the seams between sections, the peeps) for the inflow to be concentrated solely at the top holes. But having the top holes helps even out the inflows.

The easiest way I have discovered to process it is... don't. Head on over to the big river in S. America dot com and order cosmetic grade zinc oxide in 4 lb bags. It is already finely ground. Upon opening, store it in an airtight jar.

What @PeterH said. Neph sye is a known bad boy in the glaze chem world. It is very high in sodium, which is why it is popular. It is also slightly soluble. Sodium is an alkaline deflocculant, which results in hard panning. The sodium slowly leaches out of the neph sye and at some indeterminate point deflocs the glaze slurry and it hard pans. Also understand clay is the only material that can be flocculated to create a suspended glaze slurry. Materials such as feldspars or feldspathic materials (neph sye), other minerals such as whiting, etc., or frits do not respond to the alkaline or acidic conditions in the slurry to deflocculate or flocculate, respectively. Only clay responds to the deflocculation/flocculation process. A recipe with little or no clay, such as your recipe with a mere 5% EPK, needs a few additional percent of bentonite (a super clay) upon which to cause flocculation (if needed) by adding a mild acid such as epsom salts. And then after some time, the alkaline sodium leaches out of the neph sye and neutralizes whatever acidity in the slurry has been keeping the clay suspended, and boom, without warning it all falls down. The bentonite is not enough to stop this from happening. Dig it out and remix it with some epsom salts or vinegar to neutralize the excess alkalinity and restore the suspension. As for the Magma product that folks above recommend, it does not chemically flocculate the slurry. It is an artificial gum additive that mechanically suspends the glaze solids. It is unaffected by the soluble leached sodium from the neph sye. It also has other attributes, so read the cautionary statements on the label. Otherwise, it floats bricks.

That's awesome for those in Canada. Will this be available in the rest of the world?

A couple of random thoughts - As others have noted, the cone rating of the electric kiln is less about the bricks than about the amount of designed electrical power to heat the volume. But if an old kiln has a low design limit, e.g., your example of "do not heat past 2000F", that is probably a combined function of small kiln size and 2.5 inch thick brick. Those both can be limiting factors in the utility of the converted kiln. You will lose some space to the burners and exhaust, and the thinner brick will radiate more heat to the surroundings. Electric to gas conversions fall into the down draft and updraft categories, I haven't heard of a cross draft conversion. Updrafts don't need much alteration beyond a burner hole in the bottom and an exhaust hole in the top, but they tend to fire unevenly. Down draft conversions require significant alterations of the interior for bagwalls and chimney walls that take up space, so start with a big kiln so you still have some stacking space.

What Peter just said. Show us pictures of 1) the electrical rating plate on the side of the kiln, and 2) the plug and receptacle you have the kiln plugged into.

Ron, I think the only acknowledgement we will get to infer that there was a problem is this 2 sentence paragraph buried midway down the the page on the About Us/History page on their website, "In 2018, Pacer Corporation changed ownership and operations management. Under a new name and business philosophy, Pacer Minerals, LLC has improved mining practices, modernized ore sorting techniques, & restructured quality control procedures." I don't see a current materials analysis on their public website, apparently one must request that. Whatever numbers are in circulation were "published" by someone else after getting it from Pacer, hence the 3 slightly different analyses dated 2020 and 2021 in Min's chart. You mentioned that you could get another independent analysis if we could ship you some current samples. Send me your address in a private message in the upper right corner of this page and I'll send you some.

Ron, that's interesting. We know that NTYAL was run out of business for that reason. Geologists tell us that talc deposits and asbestos deposits are sometimes close together and sloppy mining practices can result in asbestos contamination of the talc output. It was alleged that NYTAL was thus contaminated, though Vanderbilt (the company that owned the mine) denied it. The cost of litigation to prove their case was too much and so they cut their losses and shut the mine. The AMTAL mine in Texas was purportedly clean, and so it became a major North American source for our talc. Your sources are now suggesting it wasn't so clean after all. We do know from the business world that Daltile, the huge wall and floor tile producer headquartered in Dallas, TX, was a significant customer. A few years ago, Daltile bought the mine from AMTAL, supposedly to improve their vertical integration controlling everything from raw materials sources to sales, but at least they continued to service the rest of the AMTAL customer base (including us mere potters). However, in 2021, Daltile reduced the customer list to exactly one, itself, and the North American ceramics world has been scrambling ever since. So, what your sources are suggesting, it was not merely Daltile buying out one of its materials suppliers to improve its own profitability, but AMTAL was happy to sell its looming liabilities. Interesting.

Apparently, yours is an earlier version of the B911T, albeit with a 15 amp plug rather than the current 20 amp plug. Despite the plug configuration, you should put it on a dedicated 20 amp circuit.

Sure, I can send a few tubs from several studios I work with that have fairly robust turnover. My recollection is that Pacer doesn't put batch numbers on the bags, so the best I can promise is it was bought from our local general supplier within the last year. @Ron Roy PM me your address. dw

I have 3 electric kilns in my personal studio. The small test kiln is the only one bought new, the others were acquired in roundabout ways. All have been renovated and Bartlett Genesis touchscreens added for total control. I also manage the community studio of the local park system where, because of a political issue at headquarters they owed me a favor, which I used to buy 4 new L&Ls to replace the Skutt dogs. Although we don't do any fancy firing, the Genesis touchscreens are foolproof for the kiln volunteers to run. At my other part-time gig, I am the studio monkey for the ceramics program at one of the campuses of the community college. There we have 4 L&Ls for bisque and cone 6 oxidation, and a Bailey gas kiln for cone 6 reduction. I am the only one there knowledgeable about the gas kiln, so several times a semester I spend the day tweaking the gas and air dials and the damper every half hour. I have it down now to even temps up and down and uniform reduction throughout in 7 hours. But that took me five years to perfect.

I am not finding anything that matches the pictures you gave. The current Cress manual kilns are all listed on this page - https://products.cressmfg.com/viewitems/ceramic-kilns/manual-3 There are 3 possibilities that partially match: the B511KT, the B711H, and the B911T in that all 3 are 6 sided, 17" outside diameter, 115 volts. All are listed as 20.5" tall, but the interior depth ranges from 4.5" to 9" deep. How deep is yours? The pictures show each as having a single switch vs. 2 on yours, and fewer peep holes than yours. So far as electrical specs, all are listed as 15 amps, requiring a 20 amp circuit. Interestingly, the 511 has a standard 15 amp 3-prong household plug while the 711 and 911 have a 20-amp plug, i.e., one of the flat prongs is crosswise so you can't plug it into a standard household outlet, it requires an outlet rated for 20 amp with one of the slots being "T" shape so it can accept either the 15 amp plug with both straight prongs or the 20 amp plug with the sideways prong. Which style plug is on your kiln?

Pictures, so we can see what the issues are... dw

There should also be a plate on it somewhere that lists the electrical requirements (voltage, amperage, watts) and the model number of the kiln. Can you show us a picture of that rating plate and the plug. Also, how many sides does it have? When you say 17", which dimension is that - outside height, inside height, outside diameter, inside diameter, and also brick thickness? Those additional details will help us narrow down exactly what you have. As for operations, manual kilns are pretty generic, and their "universal" instruction book for this style of kiln can be downloaded here - https://cressmfg.wpenginepowered.com/wp-content/uploads/BASIC-KILN-MANUAL-FOR-ABC-KILNS-1.pdf

You have several things running in different directions here, so it can be confusing. This kiln needs a 4-wire circuit. Easy enough, Sparkie checks the old circuit and maybe it is an old 4-wire job. Maybe it is also sufficient gauge to support 35 or 40 amps as required by the 125% rule. Maybe there is already a 40 amp breaker on it. If so, the circuit is good to go for this kiln. Your remaining problem is the cord on the kiln needs to be replaced. Unlike extension cords and household appliance cords, kiln power cords are made with high temperature type SEO cable to accommodate the heat buildup of long-duration full amperage current when the kiln is running on high for several hours to finish the firing. The stove cord you linked to is not quite up to that spec, but since it is rated for twice the amperage your kiln will pull, it probably will do ok. On the other hand, if the existing circuit in the wall is not sufficient, Sparkie has some work to do, and there are some choices to be made. The replacement circuit only needs a 40 amp breaker and 8 ga. 4-wire cable for this kiln. But you said you might step up to a bigger kiln in the future, so future-proof the circuit now. The biggest plug-in kilns (which are actually quite common among hobby potters) draw 48 amps and require a 60 amp breaker with 6 ga. wire (though possibly 4 ga. if the run back to the panel is really long). So, ask Sparkie to install the 6 ga. cable and put a 40 amp breaker in the panel. The cable will be a bit more expensive and seemingly overkill for now, but you will only be paying for the labor once. When you upgrade in the future, all that will be needed is a new breaker and receptacle, the expensive part of pulling the cable will already be done.

A manual kiln will teach you everything you need to know about firing a kiln, because YOU are totally responsible for everything that happens - what switches to turn on, when to turn them on, when to turn them up to the next level, how to load it so the witness cones are visible so you can turn it off at the right time, yada yada yada. There are lots of potters who have only manual kilns by choice. At the same time, there are lots of potters with modern digital controller on their new kilns who think that having pushed a particular button means that is what happened, and are shocked to learn that didn't actually happen. So, work with this one. As for the wiring, as Neil and I have noted, this one will require an older form of 240V power with 4 wires vs the usual 3 in most current 240V situations. The required amperage of the circuit is fairly narrow for any kiln. If you get a newer kiln, you will probably get one that is bigger, which will need higher amperage. The trick for this is have the electrician install wire suitable for 60 amps, but set a smaller circuit breaker appropriate for this kiln plus an outlet appropriate for the power cord you get. Then when you get the newer bigger kiln, all you have to do is swap in a bigger circuit breaker and change the outlet. The newer kiln won't need the 4th wire (the neutral), so just cap it off in the box. It's ok to run less power on bigger wires, but not ok to run more power on smaller wires. So, pay the sparkie to do it once with the big wires.

You say you have a 240V hookup for it. Be aware that the old A88B kilns used a 4-wire 120/240V hookup in which the neutral is essential. Also, kiln circuits need not only correct voltage, but also correct amperage of 125% of the nominal amperage shown on the electrical rating plate. But perhaps the hookup you have is correct? If so, carry on.

You know you are going to have some amount of water in the slurry. I start mixing my dipping glazes at a rate of 1 liter of water per 1 kg of dry recipe. That typically will yield a specific gravity of around 1.5, which will be adjusted as needed after mixing and sieving. For recipes with soda ash, I will boil half of the water in a small electric teapot, and dissolve the soda ash with that in a small bowl. It will take a few minutes of stirring and waiting until it is all dissolved, and then put that in the bucket with the rest of the water before adding the dry materials.

Dearest Hive Mind, In one of the community studios that I am associated with, we have Northstar slab roller on which one of the thickness pointers is out of whack. When the rollers are parallel for an even slab, one of the pointers is considerably off from the other (and what it should be showing). Does anyone know if there is something that I can disassemble and adjust to move the pointer back where it should be without moving the roller? dw

Oh no, Babs, don't fail on us now, we love you and need you. So, what did I ever write about elements and glazes... where do I begin... A cursory review of the infamous Orton cone tables shows 3 columns of temperatures for each of the basic types of cone. The first column of temperatures is for a slow ramp over the last 2 hours into the final temperature, the middle column is for a medium speed ramp into the final temperature, and the third column is for a fast ramp into the final temperature. A slow ramp will bend the cone at a lower final temperature than a fast ramp, as a fast ramp must continue to a higher kiln temperature before the heatwork has penetrated the ceramic and the cone bends. Elements, as they wear out, produce less and less heat, which means the kiln will heat slower and slower (i.e., take longer and longer), particularly at the higher temperatures of mid-fire and high-fire clay bodies and glazes. A Bartlett or Orton kiln controller (Skutt controllers and the L&L DynaTrol are private label Bartletts, and the Paragon Sentry line is a private label Orton) that is programmed using a custom ramp-hold sequence to finish at a particular ramp rate to a particular temperature will continue to fire to the assigned temperature regardless of the actual ramp rate the elements can achieve in their weakened state (until the elements are so weak they just can't manage any increase in the kiln temperature, and then you get the dreaded E1 failure). Thus, if you are running a program with a set point of 1222℃ at 60℃/hour expecting it to produce a nice cone 6 per the Orton chart - but your elements are so worn that they can only manage 15℃/hour at the end - the kiln still will go to 1222℃ because that is what is programmed, but at the slower rate because that's all the kiln can do. Looking further in the Orton cone table, 1222℃ at 15℃/hour is cone 9, seriously overfired. (I'm just pulling these numbers from the table for the purpose of discussion, your studio practice and kiln condition may be different.) All that said about custom ramp-hold programs, there is the other side of the Orton and Bartlett controllers - the cone-fire method. You enter a speed and a cone number via the keypad, and the controller knows what to do. The cone-fire method on both these controller types contains some hidden adaptive programming that monitors the actual ramp rate in the final segment in real time. If the kiln is lagging, the controller will adjust the set point down using a proprietary algorithm from Orton so that a proper bend of the cone will occur at an appropriately lower final temperature. Using the above example, if you have set a cone 6 medium speed firing, but the elements are so worn they can only manage 15℃/hour at the end, the controller will stop at 1185℃, 37 degrees early, for a perfectly bent cone 6. Similarly, if you set a fast firing and your elements are still sufficiently robust to accomplish the higher ramp rate, the controller will automatically proceed to a higher temperature. Note that this adaptive behavior is only available in the cone-fire method. If you are using custom ramp-hold programming, you need to watch your cones and adjust your final set point to match the cone behavior. And when you install new elements that can actually maintain the ramp you set, you need to watch your cones and adjust your final set point to match the cone behavior. But alas, I repeat myself. Keep calm and carry on. Especially carry on .

Your Skutt kiln has a nice electronic controller. For firing to a particular cone, use the pre-programmed cone fire profiles. The schedules that are in the cone fire programs are just fine as is. Use a slow speed for bisque to cone 04, and medium speed for the glaze firings to 6 or 9.

In my experience, heat is heat and time is time. I have not noticed much difference between my bigger kiln full of mugs and programmed for a slow cool and my little test kiln with 2 mugs programmed for the same slow cool. Both of my kilns have the same Bartlett Genesis controllers so I know both pre-programmed slow cools are are the same. Unless your older E23 has a Genesis as an upgrade (L&L now installs Genesis controllers as default) you would need to dig into your controllers to precisely match the slow cools. (But minor differences in a slow cool usually don't cause serious differences in the glaze, so don't get your knickers in too much of a knot.) However, note that the Bartlett controllers all have an adaptive feature in the cone-fire programming that adjusts the final temperature in real time based on the actual rate of increase being sensed in the final segment. If you push the button for a fast cone X that has an aggressive heating rate, the controller will run past the assumed final temperature to accomplish the proper cone bend as shown in the Orton cone table. Similarly, if you set a slow fire, it will stop short of the assumed final temperature just as shown in the Orton cone table for a slower ramp. The kicker here is that if your elements are worn and your kiln just can't keep up the assumed 120F/hour for the medium column in the Orton cone table, the controller will automatically scale back the final temperature and you will still get a good cone bend (until things get so bad you get the dreaded E1 error). But, and here is the big BUT!, if you program a custom ramp-hold that you think exactly repeats a cone-fire profile to a particular final temperature and your kiln has worn elements that are slowing down, the controller no longer adapts. It will fire to the specified final temperature even though the elements are slowing down, and it will be overfired. So, be careful when programming a custom ramp-hold and be sure your kiln elements are in good enough shape to actually maintain the programmed ramp(s).

The new small kiln will not fire faster than the big one, as the firing up speed is managed by the digital controller. However, the little kiln will cool much much much! faster than the E23. The glossiest glazes are not affected by the cooling rate, they will be glossy even in a slower cool. Glazes that are expected to be less glossy or matte achieve their surface during the cooling, and if the cooling is too fast, the nice microcrystalline surface will not develop. A large kiln such as your E23 will retain heat better (larger size, more thermal mass inside from more ware and shelves) and the less glossy glazes will often be nice enough (though probably more interesting if you program a slow cool). With the test kiln cooling so fast, everything will be glossy. All is not lost - program it for a slow cool and the controller will manage the cool-down for you. The nuance here is that the conventional programmed slow cooling will be slower than the big E23's natural "just turn it off" cooling, so you are still going to get different outcomes between the two kilns - unless you a) program both kilns with the same cool down sequence, or b) get some diagnostic equipment to precisely document the minute-by-minute natural cooling performance of the E23 and replicate that in a custom program for the little kiln.

I am a big fan of the L&L kilns. I am not personally familiar with Evenheat, Jen-Ken, or Olympic, but from all the noise in the various pottery groups on the intertubes, most of the users of those brands appear not to be production users, and most of them seem to be happy enough with their kilns. I have worked with both Skutt and L&L in several community studios with a lot of volume, and much prefer the L&L. The Skutt PK models are designed for high production environments and are pretty sturdy kilns compared to their regular line, but you can get an equivalent level from L&L with their quad element option. If you want even firing, the L&L has zone control (multiple thermocouples) as standard; you will pay extra for it from Skutt. If you get zone control from Skutt, it will manage the separate zones independently as expected, but the 3 thermocouples cannot be calibrated separately (at least in those at one studio I work with that has Skutts), you get one thermocouple offset that applies to all 3 regardless of whether a particular zone is running hotter or cooler than the others. If you are going to do your own maintenance, the hard ceramic element holders in the L&L make element changes a breeze. The Skutt pins and channels in the soft brick are hateful. As for the SSRs, they seem to be an available option for only a few of the Skutt models, so do some more comparative research if that is priority for you. Regarding the Skutt touchscreen vs. the Genesis (which is now standard on L&L kilns, you will pay extra for the Skutt KMT versions of their kilns), you have the question backwards. Both are made by Bartlett, but the Skutt version is in different form factor to match the way they designed their control panel. The screens and features are mostly comparable, but Skutt does not offer much of a written user manual, instead they build an FAQ of sorts into a help menu behind a button on the screen. Further (which borders on criminal IMO), Skutt has removed the slow cool option from the cone-fire programming. If you wish to slow cool a firing, you must construct a custom ramp-hold program that mimics the desired cone-fire program and append additional segments for the slow cool. In addition to being inconvenient, you lose access to the adaptive capability of the cone-fire method. (With this feature, either controller will monitor the ramp rate in the final segment into the target cone and automatically modify the target temperature (e.g., lower the target temperature if the ramp is lagging due to worn elements) in accordance with an algorithm licensed from Orton. In a ramp-hold program, the target temperature is absolute as programmed, which means a slower ramp due to worn elements will result in an overfire.) The Genesis has an on-off checkbox in the settings for appending a slow cooling segment to a cone-fire program. The only feature Skutt offers over the standard Genesis is an extra cost subscription to a cloud data service into which the controller will automatically upload data from every firing for later retrieval and analysis. The Genesis only retains data for the last 10 firings. If you don't subscribe to the Skutt Kiln Link cloud service, their version also retains data for just the last 10 firings. The foregoing is my opinion and should not be confused with what anybody else may think.. dw