Tuesday, May 28, 2013

Pottery Compost Crocks - "Part Two - Lids"

Counter Top Compost Crock

I made three crocks. The one above is the smallest of the three.

My last post left off with me trying to figuring out how to make a vented lid that would accommodate a charcoal filter.  Here's what I decided on....

I threw a lid with a flange that was pulled inward to secure a commercially made charcoal filter disc.

For the large crock I decided to go with an over the rim covered lid.  I made a custom sleeve to fit a small filter.
Using my biscuit cutters, I cut a doughnut shape. 
I formed it onto one of my hump molds to get the shape I needed. I left it there until it got soft leather hard.
I carved the vent holes, scored, applied magic water and attached the custom piece to the underside of the lid.

For a nice finished look and to assure a strong attachment, I sealed the seam with clay.
This is the finished custom filter sleeve for the flat lid.
After I attached the strap handle, I applied wax resist on the top side of the custom sleeve, so it would dry slow and hopefully not crack.

So that's about it.  It was a fun project and I learned a lot.  I'll post a photo once they are glazed and fired.

Thanks for reading and happy clay days :)

©copyright Cindy Gilliland.

Saturday, May 25, 2013

Counter Top Compost Crock - "Part One"

Wheel Thrown Compost Crock
by DirtKicker Pottery

I took on the challenge to  make a wheel thrown Compost Crock because it sounded like a great way to stretch my throwing skills.   I didn't know much about composting crocks, so I did some research and found out they are not just a garbage can for banana peels.  A functional compost crock requires some features which turned out to be hurdles during the making process.

My goal was to make the crock with a fired size of 9-10" tall and 7-8" wide.  This would mean I would need to throw 11" tall and 8-9" wide.  Easy enough.... umm not really.  From the beginning I made a big mistake - I should not have used my soft porcelain blend clay.   Not only is porcelain expensive for this size piece, it's difficult to get the height needed. It would be best to use a clay with some grog to help make it easier to pull the crock walls taller and thinner.

I don't have much experience throwing larger pieces, so I thought I would start out with a 5lb lump which was too small. I only got about 8" high.   Then I moved on to 6lbs, which I got to 9" high.  Finally I threw 7.5lbs, which was the ticket for 11" tall and 8.5" wide. 
Most of my photos are with the 6lb lump.  By the time I got to the 7.5lb lump, I forgot about taking photos.
Centering 6-8lbs lumps wasn't bad.  I just started with centering the top portion of the clay and slowly cone centered the entire lump.
When opening I used the heel of my hand.

I left the bottom about 1/3" thick and compressed it well.

When pulling up the walls I kept the pulls as even as possible.  I left a good amount of clay at the rim for strength.  I kept the top fairly narrow until the final rib shaping.   As the walls got taller I slowed the speed of the wheel so I wouldn't lose center.

Final thrown crock
7.5lbs - 11" tall, 8.5" wide

I decided to design this crock to be used with a flanged lid on a straight rim.  Many people who use compost crocks use the biodegradable crock liners and it turns out that a lid gallery makes it really difficult to remove the full liners from the crock.

The lid is a whole other can of worms (pun intended).

Apparently the compost sweats inside the crock and condensation can form under the lid, so the lid needs ventilation holes and a sleeve to fit a carbon filter.  So that is the next hurdle that I will address.   

To be continued…

All designs, photos and content herein are owned by and ©copyright Cindy Gilliland.