Jump to content

algebraist

Members
  • Content Count

    48
  • Joined

  • Last visited

About algebraist

  • Rank
    Advanced Member

Profile Information

  • Gender
    Not Telling
  • Location
    Massachusetts
  1. An update, in case anyone else finds themselves with similar trouble: I finally had my appointment with the hand specialist; it's "trigger thumb," which is "trigger finger" of the thumb. As you bend the thumb, it snaps open or closed, and this mostly happens after resting it for a long time -- like when you wake up. He wants me to spend another 8 weeks using a brace pretty aggressively -- always at night and sometimes during the day, and if that doesn't do it I get the cortisone shot, maybe another if necessary, and eventually there is surgery. But probably it won't go that far. I've been doing almost no throwing, and will have to keep it that way for a while. And my other thumb just started having the same problem -- no pain yet, but occasional snapping open and closed. Probably it got stressed by picking up all the slack of going thumbless with my right hand -- try turning a key or closing a ziploc bag -- nightmare.
  2. If you want to continue reading, the following is an account of what a moron I am. It turns out that carefully explaining it here led me to figure out my boneheaded maneuver. Basically I mixed a lot of glaze and it came out all wrong. One of my speculations below is that maybe my scale is inaccurate at heavier weights. So after posting this I got the bright idea to test it, and I found a 2kg bag of dog food and brought it into the studio and put it on the scale. Imagine my surprise when the scale read 4 thousand 4 hundred and something. It seems I had the scale set to *pounds* and was reading it as grams. What with old eyes and bits of clay on the display, the decimal point was unnoticeable, as was the "lb" in the corner. So basically I added a little less than half of every ingredient except water! Mystery solved. The good news is that with a little work I can salvage the glaze. The bad news is that it doesn't change the fact that I'm a moron. Oh well, you work with what you've got! The short story is that I just tried to make a 5 gallon batch of a glaze I like, when the largest batch I've made before is about a gallon. The results are confusing. The facts: 1) My basic recipe (which I will include at the end) is for 100 grams, plus an addition of 15 grams of Zircopax and 1.3 grams Veegum CER, for 116.3 grams total. But I will refer to it hereafter as 100 grams, as one unit of the glaze. 2) 30 times this recipe with the addition of 3 quarts of water made just over 1 gallon. That's what I've been happily using. 3) Yesterday I mixed up 120 times the recipe and added 12 quarts (3 gallons) of water. I used my new Jiffy mixer at the end of a drill, and sieved 3 times (usually I only sieve twice) with an 80 mesh sieve. The surprises: A) The glaze is much thinner (as in less viscous) than usual, and There's a lot less of it than I thought there would be -- it comes up to about 9.5 inches in a 5 gallon bucket (which is about 14.5 inches tall). Making 4 times the recipe that yielded a little more than a gallon should have yielded more than 4 gallons. Here are my speculations: i) Maybe my scale is inaccurate at heavier weights, so that when I was weighing out 2 or 3 kilograms of various ingredients (instead of the usual 1/4 of that amount), it was always giving a higher reading than what was really present. That would account for the thinness, and maybe also the amount. In this case I figure I can just let water evaporate until it's the right consistency, and still have a good glaze. ii) I've been using 1.3% "Veegum CER" in all my glazes. It gives a good consistency and good handling properties. Probably I could get similar results with bentonite, but I continue to use this because it's been working for me, and I don't want to start a new round of testing to replace something I'm happy with. But I wonder: Maybe it doesn't scale up nicely, and in larger quantities a higher percentage is needed? That doesn't really make sense to me, and wouldn't explain the discrepancy in the amount, but seems worth mentioning especially because usually I can mix a glaze one day and all the ingredients stay beautifully suspended for many days, even a week or two. The batch I mixed yesterday already has the solids all settled out on the bottom. (Even when I mixed it back up, though, it's still very thin.) iii) I have a new bag of Nepheline Syenite (the one I've had for 15 years having finally run out) from a new supplier. Maybe there's something going on there. I rechecked my method of measuring the water (a line on a gallon jug -- it's right on). I suppose it's possible that I could have mis-measured some ingredient horribly, but that's not like me and would be a first (as far as I know!). For completeness the glaze is a reformulation of Hesselbeth and Roy's "Majolica" (from "Mastering Cone 6 Glazes") to use the raw materials I happen to keep on hand: Nepheline Syenite: 30.700 Ferro Frit 3195: 14.820 Wollastonite: 21.228 Pioneer Kaolin: 15.621 Silica: 17.623 Zircopax: 15.000 Veegum CER: 1.300 Thanks for any advice.
  3. Thanks everyone. Mdobay: yes, that's the idea -- the wax resist gives me a design formed of unglazed clay.
  4. If I sketch a design on bisque, then paint wax resist over it, then glaze, can I be sure that the pencil marks will burn away completely in a cone 6 glaze firing? (I realize the best answer is "try it and see," but I'd rather not delay the piece I have in mind by a firing cycle, if possible.) Thanks in advance.
  5. Thanks. It was my primary care physician who made the diagnosis; I'll be seeing him again soon and will ask about a specialist. And I'm trying to avoid the cortisone shot -- probably it's the right thing, but I've had a couple. Depending on where they do it, it can be no big deal or horribly painful. The thumb sounds like the second of those options... Thanks for the advice.
  6. I truly appreciate the offer, but I don't think it's necessary. Yesterday I searched through the many posts on centering here, and then looked up Tim See's YouTube videos on centering. Very graceful, with very little stress on the hands, and very little use of thumbs. My centering was okay in the sense that I could do it, but it seems I was powering through with bad technique. Once I'm back in the game, I'm going to be trying to mimic his technique. Thanks again.
  7. Thanks -- thumbless throwing in the future. For what it's worth, I read more about DeQuervain's Tenosynivitis (you'd think it wouldn't have taken me a month to do so), and maybe the doc got it right. In any case, I'd still like to hear from anyone else who's had similar troubles.
  8. I've been away from the wheel for about a month due to a thumb injury -- I woke up one night with severe pain in my right thumb. I hadn't been throwing that day, so I've been clinging to the hope that it's unrelated to pottery, but today, feeling mostly better, I sat back down at the wheel and immediately found the problem (and set my healing back some...). Basically, throwing is pretty stressful on the thumb. In particular, when centering by the "cone up, push down" process, during the push down phase my right thumb is braced against my left hand for stability, and there is a lot of pressure exerted on the thumb. Based on the way it hurt, I think I can safely say that it's this pressure that's giving me trouble. (The thumb also does lots of other work -- during the cone up I've been using the edge of my thumb to keep a hole from developing at the top of the mound, for example, and I suspect it gets plenty of work as well during pulling up the walls of the ware -- I couldn't fully investigate today because, in a rare show of prudence, I stopped.) I went to the doctor a couple of days after it first started hurting, and was diagnosed with "DeQuervain's Tenosynovitis," which is an inflamation of the sheath that the tendon that connects the thumb to the forearem passes through. For that I was told to wear a brace with a thumb "spica" (stabilizes the thumb), and given some exercises to do when it started healing. I now think the diagnosis is wrong, and will have to go back to my doctor to discuss it, but I figured I should also ask here in case this is the well known "Potter's Thumb" or some such. (Just Googled "potter's thumb" -- don't. Yuck. It's not that.) Experimentation has shown that wearing the brace at night is a good thing, but wearing it during the day as well is definitely bad. So far the exercises seem to neither hurt nor help. Finally, in case it helps identify the trouble for anyone who's had something similar, the pain that started suddenly one night happened when I extended my thumb out straight -- I got an immediate shooting pain accompanied by a spasm in my thumb. So I guess I am back on the injured list for a while. Luckily I have enough sitting around for a bisque firing, so I can do that and then keep myself busy glazing for a little while. If necessary I can also focus on slabs while the thumb heals. In the end, though, I definitely want to get back to the wheel, and might have to look into alternative centering techniques. Thanks in advance for any suggestions.
  9. Mine is about 15 years old, and if I rub it with a wet cloth, some blue paint still comes off. Oh well, it doesn't seem to harm anything, and I don't lose any sleep over it.
  10. Personally I don't love the idea of an apprenticeship. I think you can teach yourself pretty much anything, and what you can't you can probably find out right here. Others will disagree (passionately, I suspect), but I taught myself pottery by buying a bag of clay, a kiln, and a few books. Later I got a wheel (and some more books...). If you have the luxury of spending a lot of time at it, you will learn fast. Certainly I made mistakes that someone looking over my shoulder might have been able to save me from, but making mistakes is a good way to learn. Of course, you should do what feels right to you, and if it's an apprenticeship, cool. I will add my voice to those who say you should get a college degree; if I were you I would study something other than pottery or even art, and take whatever pottery and art classes you can fit in as electives. That way you have something to fall back on. Right now you're young and pretty much invincible, but pottery is physically demanding, and you could wake up with a bad back or some such one day down the road a decade or two. And I agree completely with those who suggest a year or two off before college -- why not, especially if you're not entirely sold on the idea. Good for you for asking for advice here. And for thinking seriously about what you want to do with your life -- so few people ever do, at any age. Finally, I will add that all this advice could be wrong. If Picasso and Jimi Hendrix were asking similar questions, telling them to go to college and then pursue painting and guitar in their spare time, or after getting a degree, would be a bad call. In the end you have to decide for yourself. Good luck with it, and let us know how it's going from time to time.
  11. It doesn't glide. The feet are something like this (not a picture of the actual feet -- just something I snagged off the web that's basically the same): I think you could replace them with rolling casters if you wanted to. Using it as a throwing stool (i.e. at the wheel), I would think that sliding would be highly undesirable...
  12. Thank you both. Mine is definitely 2" shorter, but the idea of replacing the pneumatic cylinder with a taller one is encouraging. Far more appealing than calling Speedball (the manufacturer) or ClayKing (the dealer) to complain about the height of their chair. I'll probably try it as is for a little while, and then buy a replacement cylinder. Thanks again.
  13. After reading the "What does your throwing stool look like" thread, I ordered a Speedball ST1 stool, the one that looks like this: It just arrived. Specs say it adjusts from 18" to 23", but mine adjusts from 18" to 21". And it feels short at 21". So my question is: Did I get a bad one, and it should adjust higher, or are the specs inaccurate, and I should just learn to live with it? (If those of you with one at home wouldn't mind getting out your tape measurers for a quick check, I'd appreciate it. I'm measuring to the highest part of the seat.) Thanks.
  14. Thanks, Tristan. Makes sense that you can replace just the motor -- hadn't thought about that. And you're right, I suppose I'll just make the right artistic choice and then take the consequences.
×
×
  • Create New...

Important Information

By using this site, you agree to our Terms of Use.