1. Home
  2. Pottery Crafts
  3. fix glaze that isn't absorbed by bisque ware

fix glaze that isn't absorbed by bisque ware

Hi,

I usually make my own glazes for cone 6 but had some low fire clay I'd used for several bowls and purchased a low fire spectrum glaze. It's an odd consistency--sort of sticky and gooey like thick paint and the pots just don't absorb it well when I dip them and take way too long to dry. It's not the sort of pudding-like consistency of glazes with a lot of gherstly borate. In addition the glaze pinholes. My guess is that it's intended for brushing and not dipping.

Is there something I can add to fix this so I can dip my pots? I think if I could get a nice even coat of glaze of the proper thickness that the pinholing might disappear also.

Thanks,

Janet snipped-for-privacy@amherst.edu

Reply to
Janet Price
Loading thread data ...

Janet: This is from the

formatting link
website:

"Spectrum's Glaze Thinner is a solution of sodium hexametaphosphate in water. It is a very powerful thinning agent and should be added very sparingly. For example, 2 or 3 drops in a 4 oz. jar should have a significant effect. It is a useful product for thinning glazes, underglazes, etc. when you do not want to dilute the strength of the glaze by adding water. "

Therefore, one can use water to thin Spectrum glazes, but it may dilute the colors somewhat. I tried to find a reference to sodium hexametaphosphate (phew!) but didn't have any luck. I was kind of hoping you could find it in common household chemical...oh well. I would try a bit of water first.

Hope that helps, Wayne Seidl

Reply to
wayneinkeywest

Sodium hexametaphosphate is also known as Calgon (not to be confused with CalgonITE, which has a detergent added).

Funny, I just recommended this stuff the other day on another NG to someone looking to clean scale from inside water pipes. (That's actually what it was invented for in 1929.) Turns out there are tons of uses, including (according to one reference I have) soaking beans faster for cooking! (Haven't tried that myself).

Calgon should be readily available as an add-in softening agent for laundry. Look in the supermarket aisle with other laundry products.

Hmmm. I just checked the ingredients on a box and it says: Sodium Tripolyphosphate 34% Sodium Sesquicarbonate 66% No mention of Sodium Hexametaphosphate. Could they have changed the formula for the laundry product to no longer include the real McCoy? Or is the above somehow equivalent chemically?

I'll check into this and report back...

Bob Masta dqatechATdaqartaDOTcom D A Q A R T A Data AcQuisition And Real-Time Analysis

formatting link

Reply to
Bob Masta

After a lot of Web searches, it appears that the Calgon name is still used to refer to sodium hexametaphosphate in industrial or commercial applications, but the laundry product is no longer the same. This might have something to do with phosphate reduction (or maybe cost reduction!). Anyway, if the laundry product is easy to get, you could go ahead and give it a try. Please let us know how this all turns out!

Bob Masta dqatechATdaqartaDOTcom D A Q A R T A Data AcQuisition And Real-Time Analysis

formatting link

Reply to
Bob Masta

Bob,

When I went to look for Calgon in my local supermarket, I was directed to the bath products where it was a brand name for bath oils. I did not see it in the laundry area, where I looked first. I'll check the other supermarket in town.

I don't think adding water is the right way to go to fix this. And I've emailed Axner but had no response. I should look in the clayart archives too, but I'm not sure what to search for.

Thanks,

Janet

Bob Masta wrote:

Reply to
Janet Price

Hi Janet

The Calgon is a good idea. Did you say you had pinhole problems also? Maybe if you have time and are just experimenting with the earhtenware you could develop a low fire glaze to use in your studio. I'm sure you coud find a formula suited to your need that wouldn't have so many problems. Years ago I found myself in a similar situation and eventually found the perfect glaze for my situtiion after a little experimenation. I still use it 30 years later as my primary glaze, NJ

v
Reply to
Nancy Albin

InspirePoint website is not affiliated with any of the manufacturers or service providers discussed here. All logos and trade names are the property of their respective owners.