Sunday, May 30, 2010

Foam Trimming Bat

During a recent workshop in Atlanta the topic of the Giffin Grip and trimming came up during lunch. Several attendees expressed their love for the Giffen Grip. I have a Giffin Grip and I too find it very useful. However, if the pot is not perfectly centered I find that trimming can be a little challenging. I explained that I sometimes use the Giffin Grip but that most times I use my foam bat for trimming. I received an email asking me how I made the foam bat. In case anyone else is looking for an alternative for trimming I'm posting the information here.

I went to a local cloth store and bought a couple of square yards of green half-inch this foam:

I cut the foam in the approximate shape of the bat - being careful to make it about an inch or two bigger than the bat. **You do NOT want to cut it too small**. I used a pressboard bat since I stopped using them some time ago for throwing (I found they warped when wet).

I sprayed a heavy coating of adhesive on the surface of the bat. I used standard adhesive that comes in a spray can (like spray paint) that you can get at Lowe's or Home Depot. I placed the cut-out foam on top of the bat and pressed down to ensure the entire surface of the foam mat was in contact with adhesive. I let that sit overnight. The next day I cut the foam with scissors to match the shape of the bat.

View from underneath:

View from above:
The lines you see on the foam are guides to help center. I used a Sharpie pen to do this. The bat was place on my wheel and I started it spinning at about the speed I use to center clay. I held my hand very steady (using my leg as a brace) and placed the pen on the foam bat near the center. After the first circle was complete I lifted the pen, moved it out approximately one-half inch and repeated the process until I reached the end of the foam. The centering lines have really helped and I highly recommend them.

I quickly discovered that I needed to trim pieces that were larger than the bat pictured above. While in St. Petersburg I stopped by The Highwater Clay store at St. Pete Clay and bought a large bat (3/4" thick by 22" wide). I used this bat to make a larger foam bat to trim. Here it is:

From the side showing the thickness...

Tips for centering your pot:
  1. I place the pot in the center of the bat and get it as close to the nearest marking as possible.
  2. I start the wheel turning very slowly and place my finger near the bottom of the pot.
  3. As the wheel head turns you will be able to judge how centered it is. Stop the wheel and adjust accordingly.
  4. Once centered push down on the pot to help stabilize it.
I can usually center a pot on the foam board in about 30 seconds. I like using it so much for trimming that I only use the Giffin Grip when I have to.

Good luck and I hope this explanation has helped!

Thursday, May 27, 2010

New Tumblers

I've made a lot of mugs throughout the years but never tumblers. I've always liked tumblers, but never made the time to try throwing the form. Yesterday I decided it was time to make a few:

What do you think? I'm happy with them. Now I'm thinking about what glaze(s) to use. I might try the same glaze combination I use on mugs: a liner glaze that turns out a very light blue and a fake ash glaze on the outside that is applied thicket toward the top so there's a small amount of running.

Any suggestions?

Monday, May 24, 2010

Getting Ready to Fire

For months I have been promising myself that I would take a day to make a bunch of mugs. I always found that I had other things on the agenda and the mugs got pushed to the end of the list. This weekend I stopped procrastinating and Saturday was 'Mug Day'. I threw about three dozen of them.

I found that setting them out back on the kiln in full sunlight drastically cut down the time I had to wait until they were ready for handles. No more covering them overnight with plastic, checking every few hours, etc. About an hour or so in the Florida sun and they're ready to go...

It's much less time consuming for me to throw a few dozen mugs, set them outside, and start putting handles on them an hour or so later.

This coming weekend I will be bisquing a full load in the electric kiln. Finding the time to bisque fire is tough for me. I will not leave the electric kiln on while I'm away. Also, I like to monitor it just in case something goes wrong (see my earlier post). I'm paranoid about the possibility of a fire. I might be too paranoid, but I usually play it safe when it comes to having something at 2000 degrees that's pulling 40+ amps. Due to all of this, I have to be home during the firings. This mean I have to find a weekend where I will be at home during the entire firing. That's easier said that done. This weekend my band is playing Friday night and Sunday night...so it's Saturday or bust.

Next weekend I plan on doing a raku firing. Michael Nagy, someone I met at the Charlie and Linda Riggs Workshop, lives in Tampa. He is going to drive up and do the firing with me. He is considering purchasing a clamshell raku kiln (like I have) and wants to see how it performs. I plan to try out the one-step naked raku technique I learned at the Riggs Workshop.

That's all for now. Enjoy your day!

Thursday, May 20, 2010

Vases, Vases, and More Vases

I've been throwing a ton of vases lately. I have a commission (my first) to produce a vase. Here's the latest batch:

I plan on using the one-step raku process on these vases that I learned at the Riggs' Workshop earlier this month in Atlanta. Click HERE to see videos I took during the workshop.

Thursday, May 13, 2010

More Kiln Repair

Not only did my electric kiln require repair but I discovered that my Olympic Torchbearer gas kiln wasn't working properly either. They way the Torchbearers work is that you ignite the pilot ring located below the kiln. This keeps the four main burners firing should one go out. This is accomplished by holding down a red button on the baso-magnetic value. After 30 seconds or so a magnetic value causes the gas supply to the ring to be continuous. This also enables the firing of the main burners. After some troubleshoot I discovered the baso-magnetic valve was no longer functioning properly. Here's a picture of the baso-magnetic valve:

I called Olympic Kilns and the technician I spoke with was very helpful. He said, if not covered properly, water can get down into the valve through the button assembly. I had not been covering my kiln well enough and I'm positive this is what happened. I had to order a new bas0-magnetic valve ($105.00). It arrived within a few days and installation took about five minutes. The kiln is now working properly.

Since this event I cover the kiln much better than before to assure this problem doesn't occur in the future.

I have wrapped the baso-magnetic valve especially well:

I hope this information helps anyone with a Torchbearer kiln. Keep it covered well!

Wednesday, May 12, 2010

Kiln Repair

Last week I started a bisque firing in my electric kiln. I have an L&L Jupiter kiln and I've been very happy with it. I typically use the 'easy fire - slow bisque' program to cone 08. I checked on the kiln periodically and things seemed to be going normally. Then, after several hours, I noticed the temperature was rising too quickly. I turned the kiln off (using the switch on the control panel). I continued to hear the elements heating up even though the kiln was 'off'. I pulled the plug from the wall and heard the elements stop heating. Once the kiln cooled down I began the investigation.

First I unplugged the power cables to each element set from the controller. I immediately noticed a problem with the zone 1 outlet (that controls the top two levels of elements). This is what I found:

The cord to the controller was also damaged at the plug:

I replaced the outlet as well as the cable. L&L was great to work with. I phoned in the order and the items were delivered just a few days later. After replacing these items I plugged the kiln into the wall and immediately heard the elements start to heat up...even though the kiln was turned off at the controller. Therefore, I had replace the damaged items but the problem wasn't resolved. I determined the only other thing it could be was the relay. I called L&L and ordered a new relay:

I installed the new relay and then tested the kiln once more. Everything worked perfectly.

This was my first experience with kiln repair...other than replacing elements. It wasn't too bad. I've got lots of greenware to fire. Time to get busy!