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Bill Kielb

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Posts posted by Bill Kielb

  1. The downdraft vent will help but it will not get all the fumes. Best to have a plan to vent and If you can you live with the heat or will it need to be removed.. The hole in the top can be used of plugged, the downdraft generally draws plenty of air through section and lid cracks so it’s pretty rare for folks to be drilling them in the lid these days.

    So it seems you will likely need a down draft, a way to vent the heat etc…… so a little more setup thought.

  2. Well as far as the time to fire, three days is probably spot on. A Day to load and fire, a day to cool and finally unload on the third day. Assuming all these things happen when someone is awake and present in the studio  to load and unload. Things often don’t happen perfectly on a timing basis so three days is probably realistic. With a single kiln, it’s actually a bit more complicated as somewhere bisque firings need to be done as well which often take a bit longer than the glaze firings.

    As far as four hours to answer an email, could be indicative or could just be email is not here primary job everyday. I used to chuckle at folks who sent me an email and then called within 30 minutes to see if I read it. Email was way down on my list of things to do so I would try to answer them by the end of the day.

    Most studios could use more kilns, more loaders and unloaders, etc…. I have never seen one over staffed or with too much free help so she may just be doing the best she can with the number of students / members that are there.

    I  would be inclined to believe her.

  3. 2 hours ago, jordan mcd said:

    Prior to changing elements the kiln would fire to cone 6 (pretty full load) after 12 hours. Now it bisque fires perfectly but just will not fire to cone 6. 

    You just don’t have enough power to offset the load and losses. Smaller kiln or improve the insulation of the existing  kiln. Improving is difficult on an already built kiln.

    Bartlett controllers don’t start erroring out till about 25 degrees per hour so even with a sitter this may become problematic in the final looks of the glazes. Some glazes just don’t like the super extended  firings.  Absent a decent way to insulate and given your power limitation, your  only practical recourse might be a smaller kiln with less surface area for losses.

  4. 16 hours ago, Cline Campbell Pottery said:

    Thank you for responding so helpfully.

    Bill, do you spray the piece as evenly as you can, or do you mask off the bare areas?    Do you ever use a binder like spray starch or hairspray? 

    I spray as evenly as I can and often use the half trigger- pull (air only) on the spray gun to gently dry the underglazed  areas with air. Gently from a distance so as not to push the wet glaze around. When in a hurry I have used the heat gun (gently).  Bisque to 05 has had mixed results for me, the clay still absorbs much quicker than the decorated areas so I just apply evenly as if I was spraying any custom finish, like a car for instance and drying the areas with air or heat as needed before the next coat.

    I have sprayed many heavily decorated surfaces and patience and even application has proven the most reliable for me. No binders - just smooth even coats.

    Next issue you may encounter is certain colors of underglaze applied heavily can cause some overglazes to bubble in the heaviest areas. Our experimentation revealed an overglaze that melts more completely has cured this issue for us as if the underglaze caused that area to not melt fully or evenly. It sort of looks like the opposite when first encountered as if over melted, so I thought it useful to mention if you run into this issue.

    I have sprayed, lots of underglaze art btw, often many layers to get the artists correct shadowing etc….. the piece below is to recreate the look of a gem with correct reflections etc…. It is VERY thick with layers of underglaze to get the look.




  5. 43 minutes ago, lauradeegee said:

    I had been messing around with that switch when I was trying to troubleshoot and it was in manual mode when I noticed the bottom elements getting red hot. In auto mode

    So the slowest this thing will go is the switch set on auto and the top element switch in the off position. The bottom elements will cycle on the timer(s)  until after two hours they will go to full on and stay on till the end of firing. Meanwhile starting with  the top switch off (knob arrow pointing up to 12:00) and turning counterclockwise at the end of the two hours will be as slow as it can reasonably go. If that all works, then there is a procedure to calibrate the top switch which may reveal if it is just out of calibration or needs to be replaced.

  6. Quote

    I need to find some other 6-20 receptacles? 

    They are likely both nickel plated copper which should be fine. Receptacles used to be CU/AL for compatible with copper or aluminum. Turns out aluminum was not good and receptacle makers started marking Cu  only to ensure aluminum was not used. Nickel plated stuff and brass terminals have never been an issue that I am aware of. I believe you should be fine as is.

  7. 45 minutes ago, lauradeegee said:

    Here is my new theory, maybe someone can let me know if it seems likely: There is a wiring issue with my kiln where no matter what position the knob is in,  the bottom set of elements is at full blast. That's why no matter what I do to try to control the timing of my firing, it always ends within 4 hours. 

    Do you have an automatic / manual switch? If yes, in the manual mode the bottom elements will be on. In the auto mode the bottom elements will cycle on the built in interval timers. If the interval timers have failed closed then the bottom elements will stay on all the time. Question, in auto mode do the bottom elements  cycle on and off?

  8. 1 hour ago, cadenrank said:

    might be wrong, but I believe that each section on this specific kiln is 240v, with 120v through each element, with 2 elements per section. Which puts the amps at 12 per wire, I think?

    Not likely, L1 and L2 says 240v so unless you also have a neutral then it’s 240v across the element. They could be 20 ohms each, measured in parallel would be 10 ohms for both which puts this at 24 amps per leg (L1,L2)  or just north of 5000 watts for the grouping, which then would be 12 amps per wire.……. And that would make sense. As drawn all the power from L1 leads through the element directly to L2 so no 120 v  unless there is a neutral which would generally be labeled as such.

    Just for snicks what brand and model kiln?

  9. 1 hour ago, cadenrank said:

    t would have been difficult to use one connector instead of the two for two wires.

    Hmm, If they were 10-12 then they should fit neatly. Overstrip them maybe 1- 1/4”, twist very neatly and tightly together, cut to finished length then inset in crimp connector, crimp tightly. Some folks prefer not to do this though, so the stacking face to face method is usually next best thing which means the bottom ring terminal gets bent upward a bit as well as the one on top when the bottom wire  ferrule hits the surrounding switch. Not the neatest assembly either.

    They do make ring to spade adapters btw. 

    At ten ohms and 240 v that’s 24 amps each wire , which free air likely is a #12 gauge with its own connector. Better stick with 2 connectors and two wires. Although I doubt that switch is rated 50 amps per terminal, maybe though.



  10. Each wire is designed to carry X amount of the load. If you turn two wires into one then it must carry double the load so the single wire would be sized for the proper amperage that will go through it. To do this correctly your single wire replacement leading to the number two terminal ought to be a heavier gauge. If we know the element resistance it’s certainly easy to calculate for each segment of wire. For simplicity of assembly, service, and the economics of stocking one gauge wire it’s often easier just to run the two wires in a single gauge independently. Whether terminated with spade  or ring, both wires should fit into a single crimp (get the right crimp, a 12-10 crimp fits two #12 easily) which makes the install simple.

  11. 3 hours ago, giorgiodidon said:

    hi all, sorry for the question, i cannot start the webserver,  i'd like to see it, i am waiting fot thermocouple interface and ssr to arrive, followed all steps, but it says cannot import config.py (already copyed as config.py from the exampe one) i can see the file in the kiln-controller directory

    It’s been several months since this project was complete. You might want to Direct message the ras pi guys above or search the board with the oven control program.

  12. The good news, that appears to be a neon light bulb and not a fuse.  Basic electrical troubleshooting is probably your next best as in following where power comes in checking routing and continuity through switches, fuses, etc.  If you are familiar or have someone who is, I think the next step would be to sequentially trouble shoot this path as best you can. Please observe all necessary electrical safety around live parts.

    If you post an overview type picture of the machine someone here might recognize the make / model.

  13. 33 minutes ago, Gal Levy said:

    So I will try next time the cone 5 glaze program? In the glaze website its looks that it is ok

    So it may fit better with another glaze and this time fired to cone 5: however the point was you have cone 10 clay, your goal should be to match that. If you fire cone 10 clay to less than cone 10 then the results can be less than ideal as well as predictable.  I would suggest to Research clay and vitrification or clay and firing to maturity.

    here is a nice article that may help  https://digitalfire.com/glossary/maturity


  14. Heavily underglazed areas will fill the pores of your clay so the overglaze will tend to not be absorbed as well in the areas of the heavy underglaze. When I have a highly decorated item, I spray these items and allow the decorated areas to dry before spraying another coat. If sprayed too early, I will not be able to build up a reasonable thickness of overglaze as it will be too wet and just run off.  Very similar to applying two coats of paint to your walls. If you don’t let the first coat dry long enough the second coat will never take. My experience, Patience pays dividends for these pieces and slowly build the overglaze thickness as necessary.

  15. @Gal Levy
    Your clay fires to 1280c which is cone 10, so firing to 06 will only sinter it and it will not be fully melted or vitrified. As a result, it will be very porous and will weep when filled with liquid  …….. and it’s expansion properties a bit unknown since it’s not fully baked. The glaze you are using is a lowfire product and matures cone 06/05.  It’s generally a good idea to use a glaze and clay that mature at the same temperature. If you are only working at lowfire temperatures 06/05 then you most likely want to use a lowfire clay that matures in the 1000c range. When the clay and glaze match in maturing temperature you can then find glazes that fit well with the clay reasonably reliably. Fitting this clay but under firing it always will have too much of a variety of results to depend on. 

    @neilestrick gave a very acceptable schedule to begin achieving uniform cone results. Clay really needs to be fired to a cone, not necessarily a peak temperature. The effect of heat over time is very important to fully maturing things in ceramics.  The schedule is not the issue, the products used are. The schedule is pretty universal as to how to more correctly measure heatwork though so understanding it will help greatly in the future no matter what cone you end up firing to.

  16. 4 hours ago, Gal Levy said:

    its normal?

    This is usually an indication of a glaze fit issue. Presuming all are rated for cone 06 and now fully melted then this would indicate this glaze and this clay have different enough coefficients of expansion that when fired together they do not fit. Hence the noise, and hence the likely crazing. You may have to look very closely but you ought to notice you likely have very fine cracks in the glaze. This is generally considered a glaze defect and a suitable glaze is found that will not do this. The firing schedule is a good one and ought to be confirmed with cones, do you confirm with witness cones?

    can you confirm what cone your clay and glaze are designed to fire to?

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