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Hulk

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  1. Caliper tool that indicates thickness at the other end (double ended calipers*), it's a something I wanted/needed for some time now, for I have poor judgment of thickness past the reach of thumb and first two fingers. That middle one looks handy for wares the left one doesn't fit. I like the thumbtack idea Min! *There are many options "out there" - try "double ended calipers" also turners/turning/bowl/bowl turners caliper(s)
  2. Almost 6.5 years in, I'm still sayin' retirement can be good-oh. ...important it is, imo, to stay vitally engaged (aka "busy")!
  3. With the image you might yet get some more information/ideas, please do check back Griffith. Added: If not trapped moisture flashing to steam ->boom, then some bits/particles off-gassing whose escape route is progressively closed off as the clay sinters? Curious, looks like a large flake, and given the uniform thickness of a pencil, also curious how a large piece has come off and no damage to the interior? ...almost like there was a layer, like a pastry, or crust, that flakes as it bakes.
  4. Interesting! Griffith, looks like there's a milky translucent white shiny coating on the clay within the defect area. Oops, that is glazed; the chip blew out in the bisque fire, per your first post. Is the pot thickest where the defect occurred, and if so, how thick? The long preheat should eliminate water to steam as the cause, however, depends on how damp it was going in, how hot and long the drying phase.
  5. Unstretched, de-stretched, aligned, reprogrammed, I like all of them! I like this also: "The compression is not to dewater or make the clay more dense. It is to alter the residual stress state of the clay. To reprogram its memory, so to speak." - Gavin Stairs (on potters.org) Richard Burkett's shrinkage test, same thread, demonstrates the (dramatic) difference "compression" makes - overall shrinkage 15% for stretched slab, 11% for compressed slab, 12% for "normal" slab - big difference. If pushing on the clay - against the wheel head as it revolves, but not so much that the thickness is substantially changed* - alters the density by squeezing out water, I should be able to easily squeeze water out of clay? How? I haven't any luck with that, but I haven't tried applying progressive test to discover the force required to squeeze water from clays quickly, as in the amount of time one spends compressing the base of a wheel thrown ware... *where a ridge of clay moved one way is then reversed.
  6. Hi Mudfish1, Sorry about the delay getting your 2nd post (above) approved. Forum Administration and Moderators are testing an edit to new member registration, which should reduce (perhaps eliminate) the Spam posted here. We ran #6 wire for new 48 amp kiln, a bit less than fifty feet from breaker to the fuse box by the kiln. The specs call for a 60 amp breaker, #6 wire. The difference - typical periodic loads vs. ceramic kiln - may have to do with "continuous load" - where the kiln is drawing the full 48 amps for extended periods. Please check back for updates from device/electrical authorities.
  7. Thanks Bill, thanks Jeff. I interpreted overwork as forcing the clay enough past its limit of elasticity, which I'd called shear or partial shear. For Bill, excessive trimming/burnishing. For Jeff, extended throwing time, where many passes, wet the whole time, leads to over-wet issues. From my pov, each a legit concern! In my experience, some clays tolerate more wet time than others. I do like to rib away the slip on the outside of forms, and sponge away most of the slip/wet from the insides as well. "Wetting" the clay from the outside is arrested soon as the second pass with the metal rib is complete, which is part of my process now - when wetting ceases, drying begins! A form that may not be prime for flaring out - too wet - can be ready not long after said ribbing. Clay responds to pressure, pressure and movement, imo. Where the clay is damp enough to move, trimming and ribbing/burnishing does move the clay, agreed. The clay moves, round and around. Burnishing definitely involves movement; smearing might be a good word, but it doesn't sound particularly good. Where the smear begins to separate later on, ah! I don't see where clay volume is reduced by applying pressure, nor where moisture can be squeezed out by applying pressure to clay on the wheel (in a clay filter press, well, that's different, eh?), so the term "compression" I still don't like, but am mostly over it, heh.
  8. Jeff, Bill, Curious what "overwork" means, exactly? I'm not recalling hearing/reading what is overwork in general, nor overwork specific to throwing forms. Is it where the clay has been pushed to the point of shearing? I'd observed, early on, that clay doesn't seem to recover well from being pushed to the point of shearing - best to remove, rewedge (thoroughly), then start over, which I'd classed with the more common problem, a) bubble, blob, dry or wet spot - any inconsistency - can cause the clay to flow unevenly, and somewhat less common b) where the clay moves on the bat, as problems that regularly occur on my wheel and on the others around me (Wheel I and Wheel II classes), but not discussed much. ...my thought was, why not experience these on purpose and thereby learn to recognize? Push until the clay either shears or disengages from the bat; repeat until both are clearly achieved. Put a few BBs (small, round, smooth - no sense getting hurt) in the clay, throw; try again with a soft bit of clay folded in; try again with a stiff bit folded in. ...ok, now don't do that/them.
  9. Hi Beccap, welcome to the Forum. My guess would be that harmful exposure would be accompanied by some coughing - and other symptoms/indications; however, lower level/chronic exposure over time definitely creeps up stealthily, see CDC articles here: Crystalline Silica | NIOSH | CDC As for your questions, they are (my opinion) good questions, which you might pose to your health care provider at next opportunity. Meanwhile, keep up the good practices.
  10. see Mark's post: Replacing potentiometer inside Brent pedal - Page 2 - Equipment Use and Repair - Ceramic Arts Daily Community
  11. Hi HenryCalvin, Welcome to the Forum! Ceramic clay is typically divided into categories by firing temperature. The lowest firing clays (low fire, earthenware) require 1500°F or more, which glows orange red (very hot!). Options for working at lower temperatures and/or no heat work required, I'm not familiar with. While waiting on more feedback, look into "air dry" clay - there are several. Here's an article discussing some of the options: The Best Air Dry Clays for Artists | Susie Benes
  12. Hi Virginia Murphy Pottery, welcome to the Forum! Hard to tell if the craters, smaller pits, or both are open all the way to the clay? Second question, are you seeing any pattern? ...looks like all three pitted/crater pieces have more defects up/away from the foot. If the glaze layer is consistent, maybe the thicker portions didn't pit/crater as much? The last ware, with the red glaze, that came out well? My first guess would be drop and hold*, as Bill mentioned. Here's a Tony Hansen article on the subject: Pinholing (digitalfire.com) Dropping 100°F and then holding for a half hour or more has really helped with multiple issues in my Studio...
  13. "Which do I use ?" Hard to say. I'm guessing the larger the container - the larger the mass of glaze - the longer it would spin before stopping, everything else being equal - perhaps due to more mass per unit surface area of the bucket interior, which provides the drag? Easy enough to test; mix thoroughly, pour some off to a smaller bucket, re-test. My experience is with different glazes and two gallon buckets. However, I've good results with tweaking the specific gravity and thixotropy of every glaze I've tried. Two of my glazes I don't add any Epsom salt too at all; they gel great as is. Added: 21 liters is just over 5.5 gallons, that's a lot of glaze
  14. Good idea to start with a test batch! Did the Epsom salt addition make any difference at all? My glazes, some require more Epsom salt (saturated) solution than others. A few points in specific gravity can make a difference; I run as low as 1.41 (one glaze), high as 1.46... ...after an addition, stir, stir, wait, test, then give it some time before making another addition. How to measure the "gel" - when has enough Epsom salt been added? See Tony Hansen's video clip: Thixotropy and How to Gel a Ceramic Glaze (digitalfire.com) ...stir the glaze at a repeatable and reasonable speed, then watch as the revolving mass slows and comes to a stop. I look for three to four turns before the entire mass slows to a stop, then "bounces back" just a little bit. Glaze that requires adjustments just keeps on spinning well past three or four turns, with currents of different speeds shearing against each other. For pouring and dipping, slow and deliberate motion, particularly pouring out or lifting up. A bit wetter glaze (lower specific gravity) allows more time to complete the glazing, but takes longer to dry. Hope that helps, check back for more suggestions from others, and please do update on how it goes...
  15. Hi MaryMen, welcome to the Forum! Which model? Looks like current (manual) models have wheel type cranks except the "22 inch Mini Might II" and "SRT-18" which are fitted with crank arms. If it's not possible to find an off the shelf item, adapting something looks to be straightforward. I'm not finding a detailed image/drawing depicting the handle attachment to the shaft for either model. Can you provide a close-up image of the handle attachment, the shaft diameter, and type? The SRT-18, looks like a round shaft that the handle fits over, fixed by a pin. ...how large a diameter is required - how big a handle? McMaster-Carr has a beautiful polished three spoke aluminum wheel, fourteen-inch diameter, item 6022K21 - it's expensive. They've a twelve-inch spoked dull iron wheel for less than a hundred US dollars, 6025K22 There are round, round and keyed, threaded, square, and "blank" attachment. The blank ones, machine to fit the application. Winco has a 11.8" wheel, just under a hundred bucks. Reid Supply lists several handwheels. Fixtureworks Rencol Added: tried contacting Bailey for an alternate crank?
  16. Hi Babs, No haven't tried Lakeside Pottery Clear Blue w/o CMC. Not sure why it's included; the notes don't mention anything about it. Next time mixing some up, I'll pour off some and withhold its CMC to do a side by side. My guess is the CMC is for keeping it stuck on. This blue is one of the recipes I'd selected when first making up a list of materials for glazes - was driving the truck to the big city, so. Any road, this blue and the red I use are somewhat translucent; I really like them.
  17. Garage (where one of three bays* is the "Studio") outlets protected by GFCI, per code. There are several extinguishers out there, however, they aren't mounted, thanks for the reminder! It's easy enough to forget where they are; so, in plain sight and the "same place they have always been" could help. There wasn't a smoke detector out there, nor was there one within twenty feet of the kitchen's ovens and range. There are now. Combo unit - smoke detector and CO detector - are available these days. I didn't know (or forgot) CO is slightly "lighter" than air. Apparently is does mix well, so CO detector near the floor maybe not so bad; any road, the water heater is out there, also various flammables, a car and truck, so. Before switching the wheel on, one may already be in the habit of checking the foot pedal position (particularly if one has already vroomed a mess, heh). Consider also, tuck hair, jewelry, clothing - any and all anywhere near the wheel head - securely away. Double check the torch is off and put away securely, each time. Check ground on all the circuits. Keep your feet dry. Look both ways afore stepping off the curb! ...look again ...and again... *Looking to make time to get the wall up this Winter!
  18. Welcome to the Forum botrytis! I'm not recalling finding detailed documentation on Alpine wheels. This potters.org thread might be helpful clayart - thread 'alpine electric wheels' (potters.org) Alpine may still be responsive? Alpine Kilns | Contact Us Pottery Wheel Foot Pedal Stuck To On - Equipment Use and Repair - Ceramic Arts Daily Community Refers to threads above, AND there are scans of original docs! !!! A.D. Alpine, Inc Pottery Wheel Repair - Equipment Use and Repair - Ceramic Arts Daily Community Confirms model designation (DCW-2) Amaco 1-101 Motor Hums but Wheel does not turn - Equipment Use and Repair - Ceramic Arts Daily Community Added: Forum internal search feature only returns "open" (UNarchived) threads; to search all, try using an external search engine, and include somewhat like "community.ceramicartsdaily.org" in your search string...
  19. My (limited) experience indicates that pinholes can (also) be caused by gasses expelled by the clay. In that case, I don't know if dropping and holding a) slows the gassing/fizzing down, b) allows time for the particle to complete its decomposition, or c) combination of both. Any road, the glaze would have to still be fluid enough at the hold temp to flow back together... Pinholing (digitalfire.com) Other factors that may be in play: hotter and/or longer bisque fire, to burn out offending/gassy bits more thoroughly; supply adequate oxygen during bisque and glaze fires, to burn out offending/gassy particles more thoroughly; ramping up the bisque fire time for thicker wares, as it takes longer.
  20. I'm not able to reproduce "Include" checkbox state instability using version 1.91
  21. Hi Sun, Welcome to the Forum! Good question, I don't have answers, just wanted to offer welcome, "bump" your thread, suggest calling Laguna support (when they are open), and check back here for updates/info on your thread. Please post update when your pedal is sorted!
  22. I'd re-used a propane patio heater hood - large diameter, light weight - for overhead system on previous kiln.
  23. There had been discrepancies in Orton's online materials regarding small cone deformation temperatures*. I used small cones for the kiln sitter (prior kiln), and I like them. They are a tiny bit cheaper. Here's an excerpt from the message I received from Orton Engineer (circa March 2020): Dear Sir, Thank you for contacting Orton to draw our attention to some incorrect information on our website. The small cones do in fact deform after the large cones. We have updated the information on the website. See also this thread (start at the bottom/end) Kiln Sitter cone for witness cone - Studio Operations and Making Work - Ceramic Arts Daily Community *There still are! The 2016 cone charts are all "backward" See the small cone page, SMALL CONES | Orton Ceramic "Small Cones used on the kiln shelf deform at about 9°F after Large or Self-Supporting Cones of the same number." It's just because the small ones are smaller - the cones are same material; same reason a large candle will slump in hot weather before a small one.
  24. Tony Hansen has published a few articles on low fire glazes, e.g. G1916Q (digitalfire.com)
  25. Could be the glaze layer at the rim is thinner. Could be the rims were worked more at finishing, hence sand and/or grog are more exposed. Could be a combination of both? Reglazing and refiring, hard to say; some have luck with that, some don't. Any road, building up a slightly thicker layer of glaze at the rim might help. Using glaze that doesn't move/sag much might also help. I'm curious if the problem mugs are together in the kiln, perhaps a hotter area? I've used a buff stoneware that weeps tiny droplets when fired hot. The droplets stick but can be scraped off bare clay (e.g. the foot ring). The droplets will be hidden in the glaze layer, where the glaze is thick enough, else there's a gritty feel. It's annoying! ...haven't seen it in any other clay, just the one buff stoneware.
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