Bill Kielb

just guessing here so…… Hmm, so not enough power to make temperature vs the shell losses. 1250 c recorded for a 1260c kiln. Seems reasonable actually.but maybe the green line is the set point? Assuming it’s not even close, then why is there not enough power. Brand new at 5760 Watts this barely makes cone 8. So when worn roughly 10% it will no longer make cone 8 and requires aan element change. Assuming not enough power Do you really have 5760 watts? ( measured accurately) your graph does not show the firing rate of your SSR which is firing at some preset slope and never really changes if we do not include the green plot. The lid The gap will add to increased losses. The top and bottom of your kiln will account for the greatest percentage of losses, but this kiln will not routinely make cone 8, that is a max temp when brand new. light load The more wares, the more mass the more power it will take My best guess if it’s maxing out at 1080c but as your graph shows it’s progressing at 200-260c per hour then abruptly stops it’s likely a programming issue or SSR drive related issue.

Interesting the attachments are intact yet when the material shrunk it exceeded the strength of the clay rather than bend during shrinkage. Better clay, thicker form all possibilities but handles should also have a way to shrink and uniformly bend a little as they shrink. Simple C form handles are often great examples as the perfect C often will collapse a bit into an over bent C but the handle because of its shape takes a bit of the axial stress and bends along the spine of the handle. Without getting too nerdy, some handle shapes allow the distribution of axial stress more evenly. So stronger clay may be the answer but handle shape and pre shape are something to experiment with. As others have likely said, good practice throughout production and attachment are always important some handle shapes have a bit of an over loop at the top which can distribute this stress along the clay better than having all the force converge into one spot. A little illustration of how we allow for this stress in pipe work below. Very similar to a C shaped handle.

Hmm, the “E” model is rated at cone 4 or 2100 degrees max. The controller should cone fire but with this kiln you will need to work with lowfire clay and glazes, generally known as cone 04. This kiln will not fire cone 6 or higher clay. The Bartlett manual has a bisque fire program. Your Manual here https://binst.s3.amazonaws.com/uploads/manual/asset_path/67/Operation_Manual_-_V6CF.pdf Page 25 has a typical bisque firing schedule to cone 04 and the Bartlett control allows simple cone firing programs, bisque and glaze, starting on page 9. As I mentioned you arę likely limited to firing lowfire clay and gaze because of the temperature limitations of your kilns.

What model is the Olympic and yes the Bartlett ought to run a cone fire bisque or glaze for you.

Took me a bit but I think this was your response before the split. “Hi Bill, I have a Jenn ken kiln that only fires to 1800F I have never worked with cones. I've previously worked with PMC, enameling and fused glass. Guess I need to pick up some cones. To expand, I also own an Olympic kiln that is set up for glass. I am able to program it for clay. My 3rd kiln is a Paragon 2 which has a controller that can be programmed as high as is needed. My plan is to make jewelry. I can send you pics of all 3, but I must admit, being tech savvy is not my strong suit. I will do my best” The Jen Ken is likely not suitable for clay as low fire clay and bisque temperatures are in the 1900 degree range. It sounds like you can use the Olympic or Paragon and each likely has a controller that you can just run a bisque program. Just post the model of kiln and controller for the Olympic and Paragon. In the meanwhile you will need to pick a clay and firing range you will be working in. For jewelry we always picked cone 6 and a nice porcelain fired to vitrification to make sure it had very low absorption even if unglazed and to ensure it was very sturdy. Just a personal preference though, folks do use low fire clay. post the models of your kilns and controllers, they likely will automatically fire bisque. In the meanwhile there is a bit of learning about low, mid fire and high fire clay bodies that you will need to do.

Sorry this has been here for a bit - just got back to it. This is not difficult so no worries. In general: bisque firings burn out all organics and to do that, the firing goes relatively slow (8-10) hours or even more for very “dirty” clays. What temperature (cone) are you working at and which JenKen controller / kiln do you have? Picture of the control would be helpful as well.

I have read through this and cannot tell if you are using witness cones to confirm things are “too hot”. Cones sense temperature but also time at a temperature or heat work. The target cone temperature built into the controller is a target which can change a bit depending upon the amount of heat work calculated. Often this depends on the load as well. The controller keeps calculating the heatwork which often ends on or near the target. Witness cones are the only way to know what the kiln truly fired to. In the end, the best firing for your clay and glaze is the one your glazes behave the best in.

Many folks leave them running. Adjusted correctly they only remove a tiny amount of actual kiln air. Turning it off early should save some energy, but 800c is likely too low as in bisque and even glaze things will not be entirely burned out. 1000c is probably more practical. The key IMO is properly adjusted so mostly room air is extracted at the kiln pickup and only a small amount of kiln air is ever removed. This will save your fan from overheating and reduce the likely hood of thermal shock. Glazes like oxygen, so having it on during the firing can brighten things up significantly and help preserve your elements from corrosive gasses.

I think I would opt for wiring the elements in series (high power) for each ring and feed them with their own infinite switch 240 v no nuetral. Fix up the sitter and use it to feed everything as a safety. Clearly remark everything for 240v operation with a ground. (3 wire). Just like more modern kilns that do not use a neutral. There are no 120v auxiliary loads this way so no need to run the neutral. The infinite switches will provide variability for firing. Safe neat wiring practices for load and temperature rating is also a must though IMO. 4 way switch below to give you an idea of typical operation. If you wire two elements in series they can be driven by 240 v without a neutral at their junction.

Just a thought, why not bisque fire the airbrushed underglaze then do your transfer. Seems ideal for a layered approach

Video here: https://youtu.be/CHbAnW79bq4 for Mother of Pearl application you may find handy.

Just a quick reminder, for kilns in North America electrical is a bit different as in: the breaker needs to be sized for at least 125% of the load but no greater than 150%. NEC sizing rules. Secs. 210-22(c), 220-3(a), 220-10(b), and 384-16(c) Basically they are considered a continuous resistive load. A 40 amp breaker and wiring, if my math is right.

I think your answers may be here https://community.ceramicartsdaily.org/topic/30146-do-you-grease-a-new-wheel-head-if-so-wear-and-with-what/

If you are sure it’s gold ….. For gold to be gold it needs to be applied fairly thick and uniform. If applied too lightly it fires green so this would be really hard to airbrush on to a descent thickness. And of course aerosolizing most of these are generally relatively hazardous. As mentioned above MOP (Mother of Pearl) provides a pearlescent look, not necessarily gold so are you seeking shiny gold as commonly used to decorate the rims of wares?

Just a first question, it is an old Paragon that requires 240v with a neutral and an earth ground. Do you have Two (2) 120v circuits and a fully rated Nuetral run to the machine? This should be your wiring diagram https://paragonweb.com/wp-content/uploads/A82B_A823B_A81B_A88B_AA8B_AA8B3B_WD_PL.pdf four way switch operation below requires both 120v circuits AND a nuetral.

This may help as an early observation, @Mark C will likely weigh in, he has had many of these - I believe. Even though removing the large pulley may require a puller, those that I have seen have a key way and key so to reinstall usually would require cleaning ALL the rust including sanding / dressing with very fine sandpaper / crocus cloth to remove all rust and burrs. To install usually requires lubricating and just sliding the pulley back on to its proper elevation then inserting the key in the keyway and tightening the set screw(s). Most pulleys are not press fit design so they can remain fairly easily adjustable on the shaft. The wheel bearing should be retained in a housing for pottery wheels and are generally not press fit like a fixed axle.

I think based on experience and prior records you will likely be fine unless something in there is fairly range sensitive. I Hope it works out for you.

Fair enough, just have never found a way or am aware of a way to calculate whether a glaze will craze or not, without testing.

Stroke and coat is a low fire glaze that matures at 04/05 and can be fired to cone 5 I believe, but ……. Mayco provides samples of expected color change at the higher temperature as well. So really the effect of combining two glazes is not always predictable or shall we say usually requires testing to figure out if the combination is workable. Glazes craze when the rate of expansion / contraction of the glaze differs significantly from the clay. Testing is the only reasonable way to know, it cannot be calculated or predicted.

I think as Neil mentioned above mark the reinforcing ribs on the side and top of the wheel head and take your best batt centered exactly on the wheel and positioned with the pin holes centered between the support ribs as a template and precisely mark your holes. From there center punch and drill. You should be able to center the batt very accurately by observing the edge of the wheel and edge of the batt while slowly rotating the wheel. So yes I would use the batt as a template.

I would agree! I even think you could make it out of rigid foam fairly easily sturdy enough to make a few, whatever depth you like just cut a full opening for the pool, hot glue a thin sheet of foam from shallow to the break in the deep end and slump away, including the side skirt. Ombré paint the pool, add David’s design and maybe airbrush in some waves, carve some deck texture ……. Just thinking …….

Manual here: https://www.axner.com/pdf/laguna/Pacifica_Manual_2015.pdf Page 6 has pedal adjustments and instructions ought to be on side of pedal. Also quick call to Laguna might be in order if the pedal adjustments turn out to be tension only. I would Definitely check if something is keeping it from returning fully to its minimum position like a bit of dried clay etc….

One thought that comes to mind is make a slump mold and use your normal thickness clay. A pool with skirted sides if you will.

My observation, it has no effect or it’s s minor I have never noticed. We have done thousands of underglazed pieces btw. I can say it changes how glaze is applied in that the underglazed areas are less porous, even when applied on greenware but not as much as when applied on bisque and re bisqued. I almost always spray my glazes though so relatively easy to air dry and spray the next coat.

As Kelly mentioned if this is completely closed and sealed definitely include a pinhole. I assume that means clay will run continuously under the bottom of this so it can also drag on the shelf with lots of friction when fired. You may want to add grog or a bit of alumina under it when firing to lessen the drag or friction on the shelf so it can shrink freely and evenly as it fires to prevent it from cracking as it shrinks. A salt shaker or even sprinkling type spreading is usually just fine.