Friday, December 23, 2011

Wax Chasing & Lessons learned

I worked on the first two wax castings of "Ascension". The folks at Art Castings were very helpful and Mac did some good work on the chasing. However, he was working blind, as he got her in pieces and had no real idea how she went together. Can't imagine doing that! So I learned that it's a good idea to provide a series of photos for them to work from.

Another issue was that there was some confusion over how the bronze was to be mounted onto the base. Since they didn't have a photo, they thought it was one way and realized that there wouldn't be enough metal to support the floating woman.  In reality, there was, mounted the way I had planned. So I had to go back and carve out all the wax that they had added.

Never worked with wax before so after a few hours at the foundry, I decided to pack her up and take back to my studio, since it was taking longer than I thought. You can see my desk with the various tools. The hot tool that is plugged in on my desk proved much too hot to use on the sculpt much. It vaporized the wax and melted much too aggressively to be much use to me. So I kept it on and placed my metal tools on the hot tool to heat the metal carving tools. That worked much better, overall.

It still took many hours, but that is mainly due to my inexperience and I'm sure it will go much faster next time. I may even chase the entire wax next time to gain even more understanding of the practice and to familiarize myself with what casts easily or harder to incorporate into my next sculpt. After finishing her up I took her back to Art Castings. Luckily for me, Jeanne too a look at the photoshopped image I had made explaining the mounting process - she didn't think it would work - that the stone would chip!

So I buzzed over to the Base Shop and spoke with Brian. Thanks to Brian and Jeanne, we were able to come up with a solution that will enable me to mount the sculpture as I had planned, with a bit of extra effort, and another lesson learned!

Friday, December 16, 2011

Finishing ceramic clay portrait of Harriet Tubman

 Harriet was very inspiring to sculpt. I took longer than I needed because I tried out different sculpting techniques from very impressionistic to fairly tight. I have to say that I really liked the looseness of the impressionistic version - so full of energy. However, as she neared completion the strength of her personality and her face competed with the strong strokes of the very loose version.

So I continued to refine until I felt that I struck a balance of free strokes and polish. The clay is a very heavy, firm, groggy clay called Chestnut that I got at Mile Hi Ceramics. It's an interesting clay to work with but the heavy grog can be a bit sandy to work with. I find that the grog (sandy, pebbly particles that add body and strength to a clay while reducing shrinkage rate when firing) comes to the surface when using sponging or brushing with water on the surface. However, if you push on the surface using wood or metal tools or pallets, the grog is pushed deeper into the clay and the surface is smooth - or at least smoother. I found this to be an interesting combination as I burnished a few areas where the skin would be most taught, giving a tighter, more light-reflective property to the clay and leaving the more textured, groggy clay for other areas. Very tacticile

This portrait bust of Harriet Tubman was very satisfying to sculpt. I plan on doing a 3/4 figure of her soon and the bust was a way of getting familiar with her face and features before expanding into more of the figure later.

She'll need to dry for a while before firing, so that won't take place until sometime in January.

Tuesday, December 13, 2011

Wax pour for "Ascension" Bronze casting

It was quite foggy this morning and I nearly postponed my drive down to Art Castings in Loveland. But, since I'd already filled my travel mug with hot tea and charged up my camera, I decided not to wait and I'm quite glad!

When Jeanne greeted me, she knew just where my work, "Ascension", was in the maze of other sculptor's molds and waxes. They had just poured the first two waxes and Mac was starting to chase them.

In the montage photo:

1) collection of rubber molds inside the mother-mold

2) the mother mold encasing the rubber like a clamshell

3) you can see that the rubber comes out of the shell

4) the mother mold seams together tightly

5) hole where the wax is poured in

Here are some photos of the hollow wax that was poured. Mac is working on taking out imperfections in the wax. He will also fix where the armture came through. When he reaches a certain point in the process, they will call me and I will head down to spend the day doing finish chasing and detailing until I am satisfied before preparing the wax for the bronzing process.

You can see the whole process of making a bronze at the Art Castings site

Thursday, December 1, 2011

Harriet Tubman Sculpture Portrait Demo

 Sorry so slow to post....this is from a week or more ago. I let the clay firm up some more and then cut off the top of Harriet Tubman's head to continue hollowing out more. The clay is quite heavy and thinner walls fire better taking some of the excessive weight out of the finished sculpture. As I sculpt and make changes, I can add on a lot of additional clay. When I feel the portrait getting heavy I know it's time to hollow again.

By lifting the sculpture up, I can feel not only the increased weight, but where the weight is. That allows me to target an area for additional hollowing, which keeps the piece centered. Something you'll want to keep in mind when the piece is fired and ready for professional mounting..

Here I am repairing the area that was sliced off to gain access to the interior for hollowing. After putting the piece back together, I carve out a section of the join, add more slip, then some fresh clay.