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Member Since 31 Mar 2010
Offline Last Active Dec 18 2014 03:18 PM

Posts I've Made

In Topic: Grinding

05 December 2014 - 02:12 PM

Looking good! 17 thru 19 are my favorites, they would look really nice in my home!

In Topic: Manganese Dioxide

05 December 2014 - 02:07 PM

From Edouard Bastarache M.D.Occupational & Environmental Medicine:




As Colby said Bastarache's research also indicates the fumes from the kiln are the biggest hazard. 

"The inorganic compounds do not penetrate the body via skin like some organic compounds, such as certain
Inhalation of dust or fume is the major route of entry in occupational manganese poisonning. Also inhaled large particles are ingested after mucociliary clearance from the lungs. Gastrointestinal absorption is generally low (5%). Very few poisonings have occured after ingestion."


For fired wares testing in a lab is the only way to know how much is leeching. I wouldn't use a mug with a manganese wash on the rim.

In Topic: Proper Glaze Procedure?

03 December 2014 - 03:54 PM

The way I read your original post I thought you swapped boraq for GB. There is a fair amount of magnesium carb in the second glaze in particular, it likes to crawl. You could try talc instead, so the recipe would be the same except omit the magnesium carb and add 11.5 talc to replace it and decrease the silica to 23. This keeps everything balanced even though the new total is 96. Do you use a glaze calc program?


To measure glaze slurry, getting the right specific gravity for each glaze you use is a good idea until you get to know the glaze well enough to not measure it. Keep the bisque firing the same so it's the same porosity. Put a clear cup on your scale and add water to exactly 100 grams, if you have a graduated cylinder use it instead. Mark a line on the cup where the water comes to and dump it out and thoroughly dry the cup. Now add your glaze slurry up to the line and weigh it. Take this figure and move the decimal 2 positions to the left and that's your specific gravity. Each glaze will have it's own s.g. The idea is to get the s.g. right before each glazing session and dip for the same amount of time so you are laying down the correct amount of glaze thickness. Crawling you had might just be from having too thick a glaze layer. Hope this makes sense.

In Topic: Proper Glaze Procedure?

03 December 2014 - 02:17 PM

GB is very plastic so if your glaze has that plus a fair amount of (uncalcined) clay then it could be from glaze shrinkage. Do you have 3134 or 3124? Fritted forms of boron have less problems than GB.

I haven't found it necessary to glaze inside then dry overnight before glazing outside unless the pots are very thin. For dipped and poured glazes getting the second coat on as soon as you can handle the pot seems to work best, waiting for the base glaze to dry makes problems.

Was the glaze layer overly thick? Any cracking in the glaze before it went into the kiln? Was there any dust on the pots from sanding etc.Maybe post the recipes.

In Topic: How Do You Develop You Own Aesthetic?

01 December 2014 - 10:33 PM

I think there are potter's pots and potters' glazes  and pots fort he general public.

I use my potters' pots and buy potters'pots  but my best sellers are not to my taste.

I do "like" them at the level of, well they work and are well made, just do not feed my soul.

Schitzo here .



This is the thought I have every time I use a blue glaze or slip. Blue sells, I need to sell pots therefore I make pots with blue. I don't have a single blue pot for our use in the house.


I would much prefer to make carbon trap shino glazed ware, wood or soda fired but it also comes down to what firing methods are available to me. Living in the burbs I don't have the option of firing a gas kiln let alone a woodfired one.