Ball Opener

picking out PVC pipe fittings

I made and started using this new tool, called a "ball opener" last month. I didn't know anything about the tool until I watched this Tom Whitaker video on YouTube:

The tool looked easy to make and I thought it might help some of my students, so I gave it a shot. 

my CPVC ball opener

In the video, Whitaker talks about using CPVC. I had some initial trouble finding the parts so I picked up PVC pipe and fittings. Then I found the CPVC and decided to make a version from both materials. The PVC is a little thicker and I was able to find a cross shaped center piece with four openings. The CPVC is thinner (though they are both labeled as the same size) and I only found a t-shaped center.

my double-ended PVC ball opener

Putting together the tool was really simple. I used a mitre box to cut the pipe and my husband had some primer and cement to attach the pieces. I made a mess with the primer, but the whole process was fast and easy.

adding water to the hole I started with the ball opener

The ball opener is designed to be inserted into a centered ball of clay on the wheel. The tool is pressed straight down in the center of the clay. Because the center pipe is slightly shorter than the side pipes, it will not hit the wheel head, but will leave a 1/4" or 1/2" floor in the clay. Then the tool can be pulled towards the body, opening up the ball of clay and leaving a flat floor.

opening out the floor with the ball opener

In the video, Whitaker suggests that using the tool is simple, which is true, and that the tool doesn't bounce around at all. I found that the tool did bounce, but I suspect some practice on my part will help with that. In my initial test of the tool, I only used it for roughly 15 pieces.

pulling the walls up with the ball opener in the reclaim bucket

Initially, I thought this might be an acceptable tool for beginning students. I figured it wasn't really necessary for me because I know how to throw. What surprised me is that it immediately improved my results. Out of 15 pieces I threw with this tool, 15 dried and fired through the bisque with no cracks in the floor. Without the tool I don't lose much, but I probably lose 10% to small s-cracks in the floor. 

oops, my recycled clay had some junk in it

I used both tools and both ends, which means that some of my floors were closer to 1/2" with a 1/4" wall, but still, no cracks. I even threw with some reclaim clay with no cracking. Additionally, throwing with this tool was faster. Usually it takes me longer to drill the hole, open the floor, and compress the floor. These steps were rolled into one fast step with the ball opener. 

feet with not cracks

The results were pleasing. I think I may make a dozen or so more of these tools to take to school. They won't work for bowls with rounded bottoms, but they might be a relief for students making cylinders. Students should probably still learn the old-fashioned way, but this is such a simple tool they could make one themselves for use after YVC.

Measuring Shrinkage

I talk sometimes about measuring my work so that I can account for shrinkage during firing. Clay shrinks during the drying and firing process but metal and plastic bike parts do not shrink, obviously. I need to build my ceramic sculptures a bit larger than I intend them to be when fired. The same issue comes up when building lamps, water fountains, sinks and more lamps.

Bike gear set on top of a fired shrinkage tile. The clay impression of the bike gear is visibly smaller than the gear itself.

At school I tell students we have about 12-13% shrinkage from wet to glaze fired. We tested it quite a while ago, but my clay at home I haven't tested. I suppose I could look up Seattle Pottery's listed shrinkage rate, but I'm firing to a lower temperature and mixing old clay bodies together, so it's best to check shrinkage myself.

Shrinkage tile after firing

The easiest way I know to test shrinkage is to make a shrink tile. I rolled a slab out of my clay (in this case I am using Seamix with sand from Seattle Pottery) and cut it into a rectangle at least 12 centimeters long. I used a ruler and a needle tool to mark a 10 centimeter line in the clay. I labeled the tile with the clay name and punched a hole in case I want to hang the tile later. Then I let it dry slowly before firing to prevent warping. Shrinkage can still be measured accurately with a flexible ruler on a bent tile, but it's easier if the tile stays flat.

Shrinkage tile with ruler to compare measurements before and after

  

I marked each centimeter just in case I made a mistake on one of the marks. With more marks, I can check shrinkage for 10 centimeters or each centimeter individually. (For those of you who enjoy a math challenge, go ahead an use inches for your marks, but calculating shrinkage rates and double checking measurements is much easier in a base ten system.) After firing I remeasured the original line. The new length is 9.4 centimeters. I lost .6 centimeters during firing. My shrinkage rate is 6%.

Metal rod standing inside wet clay form. Notice the 6% gap.

Knowing the shrinkage rate is helpful to give me a sense of how much the clay changes. I could buy or make a shrink rule to help with measurements (we have one in the YVCC clay studio), but my usual approach is to guess and estimate. This week I decided to guess during building and then use the fired shrinkage tile and my ruler to check my guessed measurements. 

Measuring the bike rod against the shrinkage tile measurements.

I built a form into which I will insert a tall black metal rod (the part that holds up the seat on a bicycle). I measured the diameter of the rod using my shrinkage tile. The diameter was about 3.5 marks on the tile, which translates to 3.5 centimeters before firing. (I didn't bother to check the actual diameter of the rod because it doesn't exactly matter using this method.)

Measuring the wet clay opening with standard centimeters

Interestingly, the interior diameter I had built into the form using the highly precise art of guessing was almost exactly 3.5 centimeters. Go me!

Pressing a bike part into the wet clay

For the smaller attachments, I pressed the plastic piece into the wet clay to mark the location and general shape--in this case a circle with a little bit sticking out at the top. Then I measured the plastic on my shrinkage tile and used my ruler to mark the clay with the appropriately enlarged dimensions. The result was very similar to what would have happened if I had pressed the plastic into the clay and wiggled it around a bit (my method for the metal rod) or cut out around the plastic piece using a thick cutting tool.

Impression of the plastic bike part outlined with dashes marking the scaled up measurement 

Six percent shrinkage is almost insignificant at a small scale, but being able to measure correctly becomes more important at a larger scale, such as when I am planning for large gears to be inserted into the clay. I am drying the work slowly, again, since any warping during drying will obviously result in the measurements being inaccurate. After firing I can check the ceramic openings against the actual bicycle parts to make sure my process is efficient.

Round shrinkage tile with impression of bike gear (I made this to have a visual of the size change in relation to a larger bike gear.)

Stencils

I decided to bring home this piece to work on over the weekend so I could try a few techniques in my spare time. I rarely build sculpture at work, since the majority of my classes are throwing classes and sculpture takes significantly more time than thrown pieces. This quarter I am teaching a hand-building class and wanted to work on this piece while the students were coil building to show them some steps in the process. 

my coil built piece after the weekend work

After I built the piece, I wanted to finish it to an acceptable level, though I had run out of class time and had limited hours in the studio outside of class. I decided to experiment with a couple of stenciling processes to see if they would work on this scale and with a high level of detail. 

detail view with some paper stencils adhered to the surface

I had originally intended to buy some large stickers that had delicate lines and patterning but I was unable to find any. I searched Michael's and eventually found some decorative punches in the scrapbooking area. I bought a large daisy punch by Martha Stewart because it was on sale. The pattern it creates is delicate and visually interesting and If you line up the paper differently when starting to punch the second row, you can get a twisting design as opposed to sets of circles. 

daisy punch with twisting paper "stencil"

The punch is easy to use and cuts evenly on regular paper if you put enough pressure on it. My daughter had trouble getting the leverage to get it to punch through, though she may have fared better on a lower table. I punched some used copier paper, some junk mail and one of my daughter's sheets of construction paper to use as clay stencils. I then wet the surface of the clay slightly and pressed the paper on. The paper stencils stick to the surface best if they are wet and are then pressed on. I used a paintbrush at first to wet the clay and the paper, but the thin lines of the paper started to rip so I switched to using a damp sponge and pressing gently onto the paper instead of brushing or wiping with moving strokes. 

stencils on clay surface after wiping with a wet sponge

Once the paper was stuck to the surface, I used a damp sponge to wipe away the exposed surface of the clay. Wiping the clay with a wet sponge washes away the clay and leaves a rough surface. The sand or grog that gives our class clay its grit and texture stay while the clay is washed away. The clay under the paper should be protected from the wet sponge and not wipe away. I have used this technique many times in a class demonstration, but I usually use just one relatively small, thick stencil of paper. The paper stencil, when removed, leaves a raised smooth area of clay the size and shape of the paper stencil. 

wiping in progress

I had never tried the technique on a large scale or with such delicate stencils as these. I punched several strips of stencils out of the different papers and adhered them to the leather-hard clay surface with a sponge. Once wet and pressed into the clay, the stencil stuck to the clay so I was able to wipe the surface with a sponge and not risk the paper stencil moving.

the white stencil section has not been wiped yet

The technique seemed to work relatively well, but the thin paper tended to rip and it was difficult to know how much I needed to wash away the clay surface to leave a visible texture change. I ended up hedging my bets and applying white slip inside the daisy stencils before removing the paper. If the paper stencil does not function well to protect the surface from the sponge wash, at least there will be some surface decoration that comes from all the effort of cutting and applying the stencils.

white slip has been added inside some of the daisy stencils

I have not yet removed the paper stencils, but when I do I will be able to see both the white slip decoration and what is visible of the texture change from wiping the clay surface.

In an effort to try several things on this test piece, I bought a second paper punch this weekend and used the contrasting cutouts as white slip stencils on a second area of the sculpture. I bought the second paper punch at Craft Warehouse but it was a different brand. I was disappointed that it didn't punch all the way through the paper and I had to cut out the center section of each stencil. That's 12 small snips on each piece. It gets quite repetitive and annoying.

paper stencils adhered to the leather-hard clay

I punched the stencils from paper that was in our recycle bag. I used a SpaghettiOs label and some used copier paper. I placed the labels and used a damp sponge to press them onto the clay. Once they were adhered to the clay and as flat as I could get them, I brushed white slip onto the surface of the area, covering the stencils and the exposed clay.

paper stencils with initial layer of white slip

After the slip was dry enough to touch without smearing, I used a needle tool to peel away the paper. The copier paper ripped as I peeled it off, but I was able to get the slipped top layer off. The remaining paper should burn off during the firing  or I can pick at it as the clay dries. The shiny SpaghettiOs label peeled away in one piece, leaving a perfectly clear line. Both papers leaked a little, letting slip bleed over into the decoration. When this happened I scraped away the extra slip inside the lines of the stencil with a needle tool or small carving tool.

slipped area after removing stencils

I still have some more work to do the piece, but the going is slow. Once it is finished, I should be able to glaze both areas in such a way that the clay color difference and the surface texture both remain visible or are even highlighted and made more visible.

Inventory Cards

On our furlough day before Thanksgiving, I cleaned my studio. I spend most of the rest of the weekend cleaning the house, playing, making a pinata and sewing a (not-yet-finished) puppet theater for my daughter. 

homemade cupcake piñata and a hanging puppet theater (in progress)

The other thing I accomplished over the long holiday week and weekend was to get my studio inventory to a functional state.

my inventory box: portable, flexible, non-digital

I had originally planned to purchase a database program. That is, after a colleague laughed at my Microsoft Word table-with-a-tiny-thumbnail inventory method, I planned to get a database. But I wasn't sure where to begin to look for a database. Also, I keep thinking I will get a new computer, so I should somehow wait to get the database.

Regardless, indecision contributed to inaction and last week I determined that I needed something, immediately, to function for me as a list of what work is currently in which show and the dimensions of works I plan to enter in shows. Running out to the studio each time I am preparing an application to measure and check on pieces is silly.

My new method, as I mentioned previously is decidedly low tech. But after spending a good part of my afternoon writing assignments and presentations on the computer, using a kinetic, physical tool is my preference. I can add too, annotate, and quickly modify the information on the cards. I can stack them into groups according to size, show, medium, color, or whatever I need to do. Physically moving the cards also helps me think about what I need to do with the actual works. 

some of the finished works I have on hand, ready for shows

The new approach consists of index cards in a box. The cards each have one picture of a work and written info giving dimensions, year completed and cost. If the firing or medium is unusual (i.e. not low fire ceramic), I list that. I also list the shows the work is in or has been in. In some cases I identify a work as part of a set or installation or note that a work needs repair or I want to make changes in the surface or color.

After I got all the cards made (mostly, there are a few new works I haven't photographed yet), I grouped the cards together into useful categories and binder clipped them. I have a set of works currently in shows, a set of works I have tentatively promised to a show in January, a set of works that need repair, and a set of works that are ready to be entered in shows. This latter is the most important set of works because applying to shows is high on my priority list for this winter. Applying is harder, however, when I don't know what I have available and I have to go track down the stats on the work (run out to the clay studio and measure it or look it up in my awkward computer inventory document). 

work for shows, holiday shows, and installation stacks

I also have a set of works that have sold recently or were given away. I need them in my card database because I tend to forget they sold and try to find them in the studio. I have a few cards for works that are missing and I can't remember if they sold or are packed away. I will keep these cards clipped and available in case I discover any new works in boxes next time I clean or start to repair work.

box-o-repairs

One of the extra advantages of my new (portable) file system is that I can refer to it without going out to the studio. (I can also take it out to the studio with me to make updates.) I tend to forget how much work I have in the studio. When I have a show coming up, I get panicky, thinking I don't have anything to put in the show. I have to go to the studio and start counting works on shelves or actually group work together on a table. A clipped stack of index cards has a reassuring heft that tells me I do have work. I can enter that show. And I don't have to go out to the cold studio in December to check.

missing works: did someone buy them?

Davis High School Whistles

Last Tuesday I visited a local high school to talk to a clay class. The visit was part of YVCC's Speaker's Bureau. The Speaker's Bureau is essentially a group of faculty who are available to lecture to local schools or groups on topics in their area. There are lecture topics listed that the faculty have prepared already but faculty can also work with the school or teacher to create a lecture that works for them. Since I was speaking to a clay class, I did a shortened version of a lecture on my work and I also did a project with the students.

The visit to the school was an unusual experience, very different from my regular classes. I was surprised by the facilities, I suppose I've grown accustomed to pretty good equipment at YVCC, despite the fact that the art rooms lack some of the features I see in other classrooms on campus and also lack studio features I was accustomed to in previous college studios.

Davis, the school itself, is in pretty bad shape. I was a little bit surprised by how much the building itself colored the atmosphere in the studio classroom. The art classroom is at the top of a three-story building with exterior stairs and hallways. When I arrived, a bit early for my visit, the classroom door was propped open with a bit of wood in the doorway and the class was loudly milling around the door.

This was a young group. I didn't see what they were working on since they seemed to have put stuff away by then time I arrived. Shortly after I came in, classes changed. The classroom had about 8 four-person work tables, 8 pottery wheels, a metal-smithing hood in the center of the room and a small glass fusing kiln.

Because I normally show images using Powerpoint on a computer with projector, I asked for these things. They were able to get a projector but didn't already have one in the classroom. They had a screen to pull down at one side of the classroom but the projector cart was dusty enough to show that it wasn't frequently used. It was lucky that the instructor who invited me communicated with me through several e-mails about the equipment because I would have expected a projector in the classroom, though I did ask about it to confirm. What I didn't think to ask about was whether I would be expected to bring my own computer. I did. And of course there was no cable to hook my Mac to the projector, so I had to bring that as well. They had one somewhere but it wasn't in the room or on the cart. I was also told I wouldn't be able to go online in the classroom since websites have to be pre-approved. (Yeah for college! Today I lectured to my Design class about having someone view their logos or posters with a critical eye to avoid images that can be misinterpreted. I showed them this site which might be banned in a HS.)

But the main feature of the classroom, as far as I am concerned, was the vent underneath the screen. The vent was blowing when I arrived. When it finally shut off, I realized it was responsible for about 50% of the noise in the classroom. I mean, it was loud! My voice was a little hoarse, but I don't think I could have talked over that vent all day anyway. The students seemed to have trouble listening to a full set of directions, but I've gotta say, I think the vent was partly (or mostly) to blame.

The vent blew for most of my lecture and shut off just as I began the demonstration. Another vent (I don't know where it was) started partway through the project and continued until I left. Because of the space on the projector cart, the projector was above my head and my laptop was below and facing the screen. So I stood facing the aisle between the students' tables, but with a very large cart in front of me, obstructing my view of several students. The projector blew hot air directly at my face for the duration of the lecture. I was relieved I had decided to cut out part of the lecture.

Now, to the credit of the school district, serious renovations are planned for this dump of a high school. They should begin construction in a year. Until then the students can enjoy jet-engine decibel vents in the classrooms, portables (a real trend in Yakima K-12 educational facilities), and exterior walkways and stairs that would frighten me in winter.

The limited equipment in the studio meant that students in this clay class were sharing 4 wheels. Before my visit the instructor informed me that each student had at least 1/2 an hour on the wheel this semester. By contrast, my beginning pottery students have at least 2 hours on the wheel by the end of their first class.

As you might imagine from my description of the facilities, the demonstration didn't go as smoothly as I might have liked. I may be selfish, but I don't think I can entirely blame it on me having a bad day. I have done this demonstration before. It is a tricky project but I was optimistic that we'd have 75% success. In a class of about 25 or 30, we had 2 successful whistles.

I have actually made whistles with little kids before and the kids were able to get the whistles to work. The trick with little kids is to take the whistle away as soon as it does work because they will keep blowing on it until it is soggy. I didn't have this problem with the teenagers. One problem I did have that I didn't anticipate was that the students wouldn't put their mouths close enough to the clay to test the whistle because they didn't want to get dirty.

The other thing I should do differently in the future is find a bigger set of appropriate tools. I have one nice hole maker for the mouthpiece. It is a random plastic tool that is flat and stiff and a little wider than the modeling sets at Michael's. I don't know where it came from but it works much better than the tools they had. I also didn't expect they would be sharing fettling knives but this wasn't a major problem.

One way that the project could have had a higher success rate was if I cut the holes. The teacher told me that she attended a workshop once where the person did just that. But how will they learn? I think it is more interesting to get them to understand the concept, the reason the clay makes a whistling sound. I brought several whistles of different sizes and I also brought a diagram illustrating the side view of a whistle.

I was very surprised by how hard it was for some of the students to understand the concept of what we were trying to do. Basically, a whistle needs a contained space and an opening with a sharp edge. It needs a mouthpiece that directs the air at the sharp edge. The air splits so that half of it is directed into the contained space and half of it goes out of the whistle. Though there is probably a technical term, this "split" in the air causes the whistling sound. The sound can be further adjusted by the size of the contained space or opening and the number of holes into the container (which can be covered or not to make a multi-note whistle).

It appeared, not surprisingly, that the students who had the most trouble understanding the concept were farthest back from me or were having other conversations during my explanations. However, one student still didn't understand how the angle she was cutting was different from what I instructed, even after I came over with my example and my diagram illustration.

Basically, giving the lecture was like talking to a semi-distracted lecture class, but giving the demo was a new thing altogether. I felt like everything I said needed to be repeated half a dozen times and still the students weren't quite with me. By the end it was hard to tell if it was too noisy or they weren't listening or if my vocabulary was different from theirs.

I left verbal instructions for the instructor explaining that the holes might be easier to cut when the clay is a little drier. Students who had reworked the openings several times were better off starting over again. Hopefully she had more success with their whistles another day.

Business Cards

Thanks for your help on the business cards.

I chose this image:

I had forgotten how much space I needed to leave for trimming. I have ordered business cards and postcards from Vista Print before but when I first looked at the site, I didn't see the template. Instead I just copied down the card dimensions and made my document that size. It wasn't until I went to purchase the cards and upload my image that I noticed their downloadable template. Of course the template leaves quite a bit of space to trim. I should have known this because I've done it before and we've even had students make business cards in Design: One Byte at a Time (the learning community that I co-taught the last two years). But in the end it wasn't too much hassle to add some grey space around the image.

For next time, though I think I will try to remember to take images, in the first place, that have more grey space. Because I had to add the grey background, I ended up messing with some of the original shadows and the reflected blue behind the piece. I don't know that it is a glaring problem but the piece is less grounded than it might be. I determined not to use the other card design that was suggested by Sean and my Dad because the piece seemed to be floating instead of grounded.

The red piece here doesn't appear to be on a surface.

Finishing my business cards was a goal for this fall. Another task I checked off my list today was having a clay stamp made by Socwell LLC. I've been seeing an ad in Ceramics Monthly for clay stamps made by Socwell LLC (www.4clay.com). The ad first caught my attention because the logo includes a whippet (looks like a small greyhound), which was my high school mascot. I looked closer at the ad and realized the company was located in my hometown, Whitewater, WI. The company creates custom stamps for clay and the advertised designs are more detailed and look cleaner than designs I can made out of clay. 

I usually make a few new name stamps or "maker's marks" every year for use on my functional work. (I don't often mark my sculpture--though once a woman had me sign the bottom of a sculpture with a ballpoint pen.) I usually make so many stamps because I demonstrate the technique for classes and because I lose them regularly. The clay stamps I made work fine for my initials but I like the idea of having a more detailed image.

I sent in this image for my stamp.

Socwell apparently will clean up even rough sketches in pencil. I wish I had read that more carefully before I spend hours cleaning up my original sketches, but it's too late now. The website indicates that they will send proofs of your design before making the stamp if you wish. After I did my online order I was given the option to have them send a proof if they though it was necessary. I like that: leave the decision to the professionals.

Anyway, that's two fall tasks done even before November. I'm on a roll.