Bill Kielb

They still have a web presence, it’s an old semi automated system to turn up the kiln progressively. http://www.fireright.com/knowledgebase.html

Nice job! That appears to be an infinite switch with single output control. @neilestrick may weigh in here - I think he has a favorite - Robershaw universal replacement. What might present a minor issue would be the typical rating of these switches are 3600 Watts and you are pretty close at 3300 watts. If you can get the switch out and post a picture of the actual switch ratings it would be best, but more than likely a universal switch will be just fine………… especially if when you take that switch out and read the numbers on the switch it is rated at the traditional 3600 Watts. A call to Skutt maybe best though as they can just tell you the correct switch to use. Nice job with the pictures, usually just have to resize the picture so the file size is smaller.

Thanks, no don’t kiln wash your lid, I just asked because with the typo in your post it appeared you might have. I asked about the temperature of firing the shelves because if fired hot enough, those dots are likely not carbon. So since you fired to 1100c, those dots are probably not carbon or organics and may not go away with further firing.

Makes sense, but if fired several times, then how high was my curiosity there.

Just asking, these have been fired several times and if yes to what temperature? Also curious about scraping off the lid. Did you kiln wash the underside of your lid?

@Katrina A quick google of your AC mains voltage shows 230 volts, single phase, much like most of Europe. So if true 240v rated switches are still fine for 220 v switches. Can you confirm this is an infinite switch in that it rotates smoothly and not a three position low, medium, high type selectable switch. A picture of the switch and markings on it would also clarify a whole bunch. Actually a picture of the front of the switch would likely show which it is. I assume you have researched enough to have picked a replacement part for the kiln, so if just rated safe for a higher voltage, should not be a problem. The amperage written on the kiln tag appears to be incorrect. 127/220v is / was a common designation in some countries. 3300 watts is definitely consistent with the power to operate this kiln. I think in the end a close up picture of the switch labeling will reveal exactly which switch you need and a replacement now is likely rated safe for 240v use rather than the old 220v standard. post a picture if you can - ευχαριστώ

220v in North America is an old standard that has been replaced by 240v. Electric grid suppliers have moved the voltage up over the years to reduce their transmission expenses a bit. Not everywhere has done this, but a 240v rated switch will be just fine even if you still have 220 v.

In general, more alumina could stiffen things up. You won’t know till you try and of course increasing the temperature or time at temperature gives you some control over this as well so it even fits with the suggestion to visually confirm the glaze has fully melted. Having a 15:1 ratio - well outside what could be considered normal though can create its own issues RE: glaze melt. With the Fritt you have, you are sort of stuck with a high starting silica level. I think likely worth the test to see.

Yes definite typo - sorry, from 90/10 probably through 80/20 …… so should have said 85/15. The reasoning was the Si:Al was very high mainly due to the lack of alumina so I was looking for more alumina which ought to be in your Kaolin. As far as melting at or around cone 05/04, boron in the range of 0.45 should get you there. You currently have 0.61 in one recipe and 0.70 in the other so either ought to melt well ……… even with more kaolin as it is likely this will still be greater than 0.45 boron. Additionally The Kaolin will help suspend things and ought to be more economical than the Fritt. So, 10-20% Kaolin ought to still melt, provides alumina which we appear to be short of and could help with suspension. All probably worth a try as if the end result suits you it is likely a more economical recipe. If you don’t like the result, then no, it’s just not better. Won’t know until you try it though. I think I would test 10%, 15% and 20% Kaolin - all adding up to 100% to see if I liked one over the other.

@SUZANNEHIG Just in case you need this someday getting wax where you didn’t want it…. When a candle burns efficiently ya basically get carbon dioxide and water. When a candle burns inefficiently ya get lots of soot (carbon) which you found in your kiln. By about 800f the candle wax burns away and by about 1000f it’s basically gone. So if you want to burn unwanted wax off a piece and start over, you can fire to 1200f and be reasonably sure all traces of wax and carbon will be completely gone.

I guess maybe expand or add context. Are you seeking to add an accounting, or maybe ownership ……? For accounting generally user and some qualifier such as weight and any modifiers etc… often establishes firing cost. What is the primary purpose of the info and what is the ancillary purpose if any? If an existing system that cannot be modified, the next step is often encoding to combine more information into a single entry which often means user codes etc…. Not sure I understand what you are seeking.

@LaChell Just in case it is never found - Cress produced a general manual for their ABC kilns here: https://cressmfg.wpenginepowered.com/wp-content/uploads/BASIC-KILN-MANUAL-FOR-ABC-KILNS-1.pdf

@Lilya I believe both recipes will melt at your low temperature. Fr8 would be a visual favorite and boron greater than 0.45 (0.60) ought to melt well. Just a thought, there is room in both recipes for alumina in my view as 15:1 Si:Al is high. You may want to simply test with a greater percentage EPK to achieve this. So 85% /15% may be worth a try to see if that works well and …… hey it’s probably more economical as well. Just to add, you may want to stop at Sue McLeod’s site. She has a nice way of explaining glazes, many of her instruction guides are free to download and she does conduct workshops. https://suemcleodceramics.com/

May I ask what was your favorite GB recipe and what Frits are available locally?

I am curious if you have used any glaze calculator, even Glazy will do. Regardless of the boron source, you likely will be shooting for (UMF) 0.45 boron or greater to melt at low temperatures. This may allow you more freedom to use local boron sources to at least get the melt established.

Usually a worn belt will appear dried and cracked, but enough slipping and it tends to get polished. In the old days we used belt dressing to rejuvenate. Having done that enough - new belt is a wise choice! Still needs reasonable tension though.

It is belt driven so since the belt looks to be in good shape you likely have to adjust the tension on the belt so it does not slip under normal use. Locate the tensioner and tighten it slowly trying it out. Don’t over tighten it there should be some deflection in the middle of the belt when you push on it with mild pressure. Also check that the old belt and pulleys are clean, no oils for sure. From your description, very likely just needs proper tensioning.

I’m am with @Hulk there is a strong possibility (especially new in the box) the commutator has oxidized over time and with no use this layer is thick. With power off you can spin it by hand both directions say ten or twenty revolutions. This will actually spin the motor many more revolutions which could help clean off some of the oxidation. Then, power on, 1/2 speed, get the wheel started and see if it will run up to high speed just for a handful of seconds. If it runs smoothly on its own at high speed and does not struggle then letting it spin for a few minutes may get the commutator cleaned off sufficiently and regular use will prevent this from occurring. If the commutator has to be hand cleaned, then something a motor tech is probably better suited for as the Artista parts list does not appear to have removable brushes listed.

Looks like 4 elements per set so that may be influencing the various prices you see. If worn, then all get replaced, they wear together, so for one section, one set is needed which means 4 elements per set. the elements should glow even if worn so you may not have run it long enough, or check you have 240 volts. When kilns are idle for years generally dust and oils will burn off. This will go away after the element temperature reaches 800-1000 f. here is a decent copy of your manual https://aakilns.com.au/pdf/Duncan_Kiln_Service_Manual.pdf. Your model appears to be listed and a wiring diagram is included in the manual.

@mxdsa Your belt tensioner is missing. See the pictures below and the area marked by the revision bubbles. Check your belt deflection if excessive you will need to increase the tension with what you have. Looks like a nut on that threaded bolt that goes through the plate. Loosen the underside jamb nut, tighten the plate down slowly using the top nut retensioning the belt a bit at a time until your slippage is gone. Over tightening can damage the belt, bearing and shaft so go slowly. Find the best spot and lock the plate in place with the top nut and jamb nut. The washer is likely an old rubber dust / splash guard to help shield the bearing. I am guessing it has dried and become brittle.

Sorry to hear that. I have been entering contracts for years that require specific additional insureds. Sorry to see it’s caught up with your shows.

GB is no longer mined. Several years ago Laguna purchased a whole bunch thought to be spoils. The mine has been closed for many years and in its hey day was used to encase underground nuclear tests. It’s never really been something mined for potters and I would expect the price will continue to rise.

Just a thought It might be easier by weight which correlates to the energy needed to fire better and maybe add a few easy baselines on size for the perceived worth of the real estate inside. Firing a bunch of small plates / plaques that are heavy but not tall takes more shelves, hence more weight hence significant energy. Often the mass of the shelves ends up to be the same or more than the pots. Some of the schemes I have seen is if it fits in box a,b,c then multiply the weight by ……….. similar to getting on an airplane. The weight often correlates to the size a bit as well. Encouraging throwing lighter, generally a good thing, encouraging throwing smaller often not as much of an issue.

Bisque firing (your first firing) is generally done at a low temperature like cone 04. The leading zero is very important, it is much cooler than cone 4. The purpose of the bisque firing is to sinter the material together and burnout organic impurities which could off gas and affect your finished glaze results. The low temperature or bisque firing leaves the clay in a state where it is very absorbent and ready for decorating. Do you bisque fire and if so what cone do you bisque to?

From what I can see, these tests appear to not report false positive below 1mg / cm2 with 95% confidence. I guess we need to define “trace” amounts that would constitute not having lead. Some info from the EPA https://www.epa.gov/lead/hazard-standards-and-clearance-levels-lead-paint-dust-and-soil-tsca-sections-402-and-403 Allowable levels of dust are fairly low with an emphasis to not aerosolize lead by heating, scraping etc…..