I'm experimenting with a number of ways to try to get better mocha diffusion. I just boiled up some nasty tobacco tea. I understand that it's best to let it all stand for a week. During that time a bacterial scum is supposed to form on the surface. My question is, does this bacteria chemically add something useful to the tobacco tea or is it just a random annoyance. I ask because putting a wine bubbler on the container with this nasty goop would likely inhibit the scum from forming.

Views: 1953

Reply to This

Replies to This Discussion

A ceramic "mocha diffusion" is merely a ceramic colorant mixed with an acid. The acid eats through the slip layer and carries the color with it in the patterns the acid eats.

http://ceramicartsdaily.org/pottery-making-techniques/ceramic-decor...

As this essay points out, any acid can be used "citric acid, lemon juice, urine, coffee or vinegar, particularly natural apple-cider vinegar." Just because a potter a long time ago began to use nicotinic acid from tobacco doesn't mean that's the best choice.

Google remains one of the best resources people working in ceramics have at their disposal.

Thanks, Norm. Your link leads to an excellent article and video excerpt from Robin Hopper that is detailed enough to get anyone started.

Note the caution about commercial clay bodies not having the right alkaline balance to strongly interact with the acid slip. I gather he is referring to making either the  base slip or the acid slip from the commercial body you might be working with. He gives a recipe for a suitable slip. He speaks of losing dendritic trails under glaze, so at cone 6, we might want to only spray on enough clear glaze to get a surface seal rather than a perceptible pane of clear glaze over the slips.

Hopefully, others with more experience, will chime in with more actual results and techniques.

Reply to Discussion

RSS

Videos

  • Add Videos
  • View All

Use These Links to Support Us

Low cost flat lapping disc can be used on you potters wheel if you, drill bat pin holes in it, and provide a trickle of water to cool it. At amazon.com, 120 grit for aggressive material removal. Click the image to purchase 

Members have had great things to say about John Britt's new book, Mid-Range Glazes. Click the image to buy from Amazon.com

Purchase Glazes Cone 6 by Michael Bailey, The Potters Book of Glaze Recipes by Emmanuel Cooper, or Making Marks by Robin Hopper, all available at amazon.comMastering Cone 6 Glazes by John Hesselberth & Ron Roy is now out of print.

Harbor Freight is a great place to find unbeatable prices for better HVLP spray guns with stainless steel parts and serviceable economy models, as well as detail guns, all tested by our members for spraying glazes, as well as compressors to power the guns. As yet no one has tested and commented on the remarkably inexpensive air brushes at harbor freight.

The critter siphon gun is a spray alternative that is well liked by some of our members, and is available at amazon.

Amazon is also a competitive source for photo light tents for shooting professional quality pictures of your work. They also have the EZ Cube brand favored by several of our members. You might also want to purchase the book Photographing Arts, Crafts and Collectibles . . .

If you are up to creating videos of your work or techniques you might want to invest in a flip video camera

Following are a few scales useful for potters. Ohaus Triple Pro Mechanical Triple Beam Balance, 2610g x 0.1g, with Tare $169.00

And finally a low cost clone of the OHaus. The Adam Equipment TBB2610T Triple Beam Mechanical Balance With Tare Beam $99.62

ebay is a great alternative for many tools and the equipment used in the ceramics studio - kilns, wheels, extruders, slab rollers are often listed there both new and used.

Tips for Members

If you just want to spout off, it is best accomplished as a blog posting. If you want to get more guidance and ideas from other members, ask a question as a new discussion topic. In the upper right corner of the lists for both types of posting, you will find an "+Add " button. Clicking it will open an editor where you create your posting. 4/16/2014

© 2024   Created by Andrea Wolf.   Powered by

Badges  |  Report an Issue  |  Terms of Service