Jump to content
Sign in to follow this  
mayaearth

Reclaiming clay scraps

Recommended Posts

mayaearth    0

I recently reclaimed a couple buckets of a variety of stoneware clays that I've been collecting over the years. All clay is the high fire, just difference sources and a small variety of colors, brown and grays. In the mixing process I did add dry fire clay to the mix (Hawthorne 35 mesh) to bring it up to a drier consistency, then wedged, and rolled into slabs. In working with the slabs, the clay was cracking as I was building, even as the clay was a workable wetness. I'm wondering if more wedging would be beneficial or if there is something else I could add during the mixing process to make the clay more workable. Thanks for any input!

Share this post


Link to post
Share on other sites
neilestrick    1,380

Ball clay would add plasticity, but here's the problem: By adding raw clay- fire clay, ball clay, whatever- you're changing the formula of the clay so that the proportion of clay to feldspar to silica gets out of whack and the clay may not fire as tight as it should. This is a bit less of an issue with cone 10 clays, but can be a big problem with cone 6 and low fire clays. When I worked as a tech for a clay supplier, I regularly received calls from teachers who suddenly had major problems with their glazes. They had been adding ball clay every time they recycled their low fire white clay, and after a few rounds the clay formula was all messed up and their glazes started shivering. No good way to fix that, either. The clay had to be replaced.

 

SO, if you're going to add raw clay to your mix, if it's a cone 10 stoneware clay I would also add about 5% feldspar and 5% flint. For cone 6 clay go with 10%. When working with one clay body, the best thing to do is either buy some dry mix of that same body, or even easier just keep a bucket of dry trimmings to mix in with the slop.

Share this post


Link to post
Share on other sites

Create an account or sign in to comment

You need to be a member in order to leave a comment

Create an account

Sign up for a new account in our community. It's easy!

Register a new account

Sign in

Already have an account? Sign in here.

Sign In Now
Sign in to follow this  

×