Pres

@perkybus, Please do not take this as being snarky, but have you made certain to remove all of the packing materials from the wheel, especially from under the wheel head to the deck? Sometimes a small piece of Styrofoam or other material can get missed and cause a racket from hitting the underside of the wheel. Just a thought. best, Pres

Thanks for the great process pictures. . . @Kelly in AK. I understand the labor of love bit, but for me that is too backbreaking too far. Guess being older has its advantages as it reminds you that activities of your youth are often insanity! best, Pres

And here I have been using my hands and fist to center 20# pieces of clay on the wheel! Especially when opening up for large jar pieces. . .pounding the fist into the center of the centered clay while the wheel is turning slowly is almost therapeutic. Guess I'll have to carve one of these out. best, Pres

@GLR, When you roll out your slabs do you start with a thick long piece of clay lying parallel to the roller, or do you start with a thick slab? I used to get this sort of thing with slab rollers, and then I started throwing the clay sideways onto a table to stretch/lengthen the clay into a thick slab then rolled this out. It did help, that looks like the clay is getting rolled over itself forming the air bubble like crease. best, Pres

I haven't had pug mill at home, but do remember the Walker at the HS. I would always be amazed at the clay that came out of the machine. Throw in some scraps from the hanbuilders, some slop from the throwers, and run through twice to have great clay. I never noticed any auger marks in the clay no matter which way I cut it. As long as it didn't dog ear on me it was good to go. I think that the side delivery at the end of the auger run had something to do with the compressed body and the lack of auger spirals. It was also easy to cut a cutting frame for 3 lb throwing pieces no matter what angle. best, Pres

Caroline yes on both counts. If looking for books, you can also look up. . . The Complete Guide to Mid-Range Glazes, John Britt, ISBN 978-1-4547-0777-6. Very well organized and a wide variety of glaze categories and explanations. As with any new glaze, I highly recommend testing, testing, testing. In my later years, I cheated on that requiring that 2nd semester wheel throwing students had to include 20 glaze test tiles in their final portfolio. These were required to have single glaze, and multiple glaze test tiles so that layering of glazes was explored. We made their work a little easier by having a test tile extruder die that would make two strips of self standing test tiles tat were cut to 11/2 inch pieces. best, Pres

Welcome to the forum, @Caroline Ennis, I hope you enjoy your time here and find some useful answers. I used a combination of glazes from the M^6 book, and from Bill Van Gilder, along with some glazes that were commercial from Minnesota clay and ART. The Van Gilder glazes played well with the glazes from M^6 and I still use some of these today. My liner glaze that I use is a transparent liner glaze that I added some opacifiers to for a white over darker clay bodies. Mixing your own should stretch your budget if you have been using commercials up to this point. However, the first year of buying materials and equipment can be expensive. best, Pres

Another thought here would be to salt the kiln shelf with grog both for the bisque and the glaze firing. It may, not guaranteed, ease the stress enough. I used to keep a salt shaker with grog in it to salt the shelves when teaching in HS. It requires vacuuming carefully afterward, but in many case was helpful. best, Pres

Another thought is the construction process: cast?, press mold? best, Pres

I am beginning to wonder if the clay is too dense for the object? Maybe it needs some grog to open it up a bit and allow for some change in the expansion/contraction of the body in firing. best, Pres

Sounds like you need to re sieve. If you can get an #80, I would try that. I always sieve twice, once into a spare container, then back into the original container after cleaning it and the sieve. best, Pres

I have been using this test for years with patens/plates, as there are times a hairline crack cannot be seen, but can be heard! best, Pres

It looks to me that they are larger than sieve size, but not certain of that. First thing I would do is to re-sieve the glaze to see if you get any particles in the sieve. Secondly, even though the glaze looks to have gone on evenly, did you wash the pot before hand? Did the pot set out before glaze firing? Was this on a lower shelf that had a shelf above with kiln wash on the bottom side? Had to ask. Is this in a bowl? best, Pres

Some pictures would be helpful, hard to tell what is going on with just a description. best, Pres

@ABlanc Considering the type of crack, and the crazing of the glaze, IMHO this is a cooling dunt, where the kiln was cooled a little to quickly for large flat pieces of this sort. I used to get some cooling dunts in the early years from overzealous cooling of the kiln, or opening too soon. How are you firing the kiln? Is it on a kiln setter, or a controller with a ramp up and down set up? best, Pres

@PeterHI have seen something like this before, but it was a wheel driven by a man below the ground while thrower was above ground. Don't remember where, but in one of my many books best, Pres.

Hi folks, no new questions in the question pool. When I was much younger, I volunteered to help on a Saturday to mix clay for the ceramics classes with the professor. The ceramics studio was on the second floor and was equipped with a Soldner like clay mixer, and a Walker pug mill. The professor had a clay body that he mixed up by bags, I remember the water hose from the sink praying over the powders as we dumped clay into the mixer. Keeping the clay wet was to keep the dust down, but it was everywhere! We mixed 3 batches that day and ran it through the Walker. Al in all, it was an 8 hr day. The professor mixed a quite a bit of slop from his slake buckets to help with plasticity, and by watching the square lugs coming out of the Walker he would tell when the clay was best. I worked with that clay the next Monday class, it was terribly short at the time, but still throwable for a second semester student. I have never mixed clay since then, deciding that I didn't have the equipment or the space resources to get into it. Heaven forbid to do it in a HS classroom, I would never get the room clean again! This got me to thinking about how many potters out there have made their own clay body or do the rely on a supplier to do the dust work! There is a recent thread on the forum lately about the buying clay premixed or dry to save on shipping costs and expenses, which also brought back the previous memory. QotW: Do you or have you ever mixed your own clay for your studio, and if you do describe your equipment and working space? best, Pres

I store my clay outside in PA, It is under my two sea kayaks, on wooden risers I built to hold 2000lb at a time. A large tarp covers the whole deal and is replaced when it wears out. Even though I have padded the kayak rack and tie down the tarp the strong winds will wear a tarp out in 2 years. My clay is shipped boxed untied. I use 2000lb in about 2 years, and yet never have problems with the clay drying out so long as the boxes stay intact. best, Pres

I have never seen larger pointed vessels thrown as all have seemed to be coil constructed with a lot of paddling and compression of layered coils. On another thought, I read somewhere that the shape of the Queri/amphora was to allow tilting of the container to pour into other containers for use. best, Pres

@GEP, I can certainly attest to the time and effort it takes to do any type of shipping situation of late. Size of boxes, and the changes in packing materials are small compared to the picture you are painting, but still a nuisance. I shipped 20 orders last year for communion sets and baptismal sets last year with a total of near $1500 in costs to the customer. This year will probably be worse. I believe that the large online shipping companies are controlling much of the sizes and delivery situations that will make it a different world for craftspeople shipping their items. This does not even include what you have mentioned in the way of social media exposure. best, Pres

I also like to layer glazes, and often will do a dip with two contrasting colors. However, I believe that contrasting color also means contrasting values, one stronger than the other. At the same time, I often spray colors on over the dipped layers to mute the line between the dipped colors. Rutile green or blue from Van Gilders glaze recipes works well for this. As the transparent glaze uses rutile(containing titanium oxide and trace elements) causing interesting breaks in texture over the other glazes as @neilestrickhas already alluded to. Running test tiles or small test pieces like shot glass vessels really help to pin point combinations. At the same time if using 3 colors it is really important to understand a little about color theory in choosing your glaze colors. best, Pres

Nancy, are you looking to make yours with the pointed/rounded base or with a flat base? I believe that part of the process is determined by the base. Thickness of the larger pots seems to be 2-4" in coils, and then the scraping will bring the walls a little thinner. flat bottoms have more stress on the bottom for weight of the walls whereas the rounded or pointed bottoms are supported with the side walls with different stress points. Interesting project. . . wish we could help more. I would think your best efforts would be to work smaller and ramp up when you get more assured/confident of your process. best, Pres

Just reminded that when I was still teaching at the HS I would run a one week workshop in Ceramics for an Intermediate school Summer camp. We did Slab project, some extrusions, and some coil work. Every day I would put pots on the two downdraft tables in the room after class at noon. In the afternoon they would be nearly bone dry, and go into the kiln with a 2 hour or so water smoke. Day 3 of class we started glazing, and by day 5 they all had about four pieces of pottery that went in the final glaze firing of two kilns. Crazy how those downdraft tables would save my bacon in end of the semester rushes. best, Pres

Use an underglaze or stain to sign then refire to a lower temp. best, Pres

I used to candle overnight wet to leather hard pots for the kids. Would start the kiln right after school 2inch lid gap, work until around 530, and head home. Next morning would check kiln for peep moisture around 645, then depending start a slow ramp to bisque 06. Worked most times, especially when there were heavy spirit houses or coil pieces in the kiln. Years ago, mid 70's I went to a workshop at Indiana State College of PA. They were doing fast firing one day with pearlite addition. Threw like crap, but the pots survived and were glaze fired in two days of the workshop! Took students to the workshop also, and they were impressed! best, Pres