jrgpots Posted July 29, 2015 Report Share Posted July 29, 2015 My family used to make lots of "made from scratch" brownies. So we premixed a large batch of dry ingedients and stored the mix in small sealed bags. It made things easier in the long run. Using this as background information, when you make up a glaze, 1. do you make a large batch and store it premixed in its dry form or its wet form? 2. Or do you mix up each batch as needed from scratch? 3. If you have a glaze which uses a more volitile substance such as soda ash, do you make large amounts or smaller amounts? Jed Link to comment Share on other sites More sharing options...
Marcia Selsor Posted July 29, 2015 Report Share Posted July 29, 2015 I do both, I have some wet mid range glazes that are very old. 10 years+ . Moved from Montana.One in particular was a mistake batch that came out very nice. I have not worked with that range for a couple of years but it is still here and ready. Mixes well. I don't mix my raku glazes until the day I apply them. I have some mixed dry. So my answer is both. Marcia Link to comment Share on other sites More sharing options...
Mark C. Posted July 29, 2015 Report Share Posted July 29, 2015 I make them all as needed except for rutile blue which I have Laguna make by the ton for me dry in 50 # sacks with my recipe-then I use it as I need it as its one less to mix up. I only have one last 50# bag left than I'll be making that until my fall order of clay and materials . At which time I will order another ton. It lasts about 5-6 years.I mix glaze almost weekly most of the year. Mark Link to comment Share on other sites More sharing options...
oldlady Posted July 29, 2015 Report Share Posted July 29, 2015 i have both. because i like some of the base glazes with differing colors, i make sure i label the dry bucket with whether or not i have added any of the things not in the base itself. like bentonite. that way, i can take 20 grams of the base and try a new color just to see whether it will work. makes testing lots of colors easy enough for even me, i hate glazing and testing. but i do it. a recent purchase of a new stain, Lobster, resulted in several tests. so far, so good. some of my glazes are from the last century. they still work, i just don't like brown and have a hard time using them up. i use a lot of green, and have 2 buckets, one wet and one dry so i can refill the wet one while working. always, always with distilled water. Link to comment Share on other sites More sharing options...
jrgpots Posted July 29, 2015 Author Report Share Posted July 29, 2015 In an old thread John Brit showed pictures of "red flambe" glaze that came from an old glaze that had "changed" while sitting around. How do I know if my mixed glaze will be stable over time or be like "red flambe?" I have bad luck with glazes.. Jed Link to comment Share on other sites More sharing options...
Callie Beller Diesel Posted July 29, 2015 Report Share Posted July 29, 2015 Peach bloom copper reds actually require aging. (flambé red?) The specific changes in the bucket haven't been well documented, so I'm not sure of the exact mechanism that makes this work. Not exactly easy to replicate the results for production I guess. Because of my summer foray into cone six, I now possess 20kg of dry mixed clear gloss that I'm doing line blends with. Left to my own devices at cone ten, I keep things mixed wet, no pre-weighing. Link to comment Share on other sites More sharing options...
jrgpots Posted July 30, 2015 Author Report Share Posted July 30, 2015 Thanks all. I will be making up three large quantities this week. Jed Link to comment Share on other sites More sharing options...
Guest JBaymore Posted July 30, 2015 Report Share Posted July 30, 2015 Wet....30 gallon garbage cans. best, ..................john Link to comment Share on other sites More sharing options...
Celia UK Posted July 30, 2015 Report Share Posted July 30, 2015 Old Lady - "always with distilled water" . Can you explain for me please? Do the variations in tap water make a significant difference? Any examples? Thank you. Link to comment Share on other sites More sharing options...
oldlady Posted July 30, 2015 Report Share Posted July 30, 2015 the water from my tap is filled with calcium. since it is an ingredient in a glaze, the water changes the amount in the glaze. so i avoid it. this is the white stuff that sticks to the taps, sticks to the buckets for washing, sticks everywhere and is unsightly. it is found in coffee machines, showerheads, and any place water sits for a time. it is easy to shine up the metal by soaking it off with an acid, vinegar, lemon juice, or something from the supermarket. this isn't as bad as the rusty stuff my sister once had. ugh, i gave her white towels and after a month they were rust colored. some people use water softeners but i hate that "still covered with soap feeling" after a shower. Link to comment Share on other sites More sharing options...
High Bridge Pottery Posted July 30, 2015 Report Share Posted July 30, 2015 Never had the need for pre-mixed dry glaze sitting around, my bucket lasts around half a year with low to medium use. If I had others using my studio regularly I might pre-mix if there was a chance of them running out. Link to comment Share on other sites More sharing options...
Celia UK Posted July 30, 2015 Report Share Posted July 30, 2015 Thanks Old Lady. Our tap water is 'hard' - calcium I assume. We have a water softener which saves all the deposits on the sink, shower cubicle, kettle, central heating pipes etc. best investment we ever made! I've neve experienced the still covered in soap feeling myself. I'm thinking a glaze test using tap water, softened and unsoftened and distilled water, would be an interesting investigation. Link to comment Share on other sites More sharing options...
High Bridge Pottery Posted July 30, 2015 Report Share Posted July 30, 2015 I wouldn't have thought there is much difference. Wiki says hard water can have 0.18 grams of CaCO3 or what not per litre of water. So 1 litre equals about 1000 grams of dry glaze, I don't feel adding 0.18 gram of extra salts would really make much difference. Even if you were adding 1g or 0.1% extra Ca/Mg/Fe I wouldn't notice. Link to comment Share on other sites More sharing options...
Celia UK Posted July 31, 2015 Report Share Posted July 31, 2015 Thanks Joel. I can carry on with tap water then, but might do some tests next time I'm in glazing mode! Link to comment Share on other sites More sharing options...
jrgpots Posted July 31, 2015 Author Report Share Posted July 31, 2015 The water softener exchanges sodium for calcium. So soft water has extra fluxing power of sodium, albeit in very small amounts. Jed Link to comment Share on other sites More sharing options...
jrgpots Posted July 31, 2015 Author Report Share Posted July 31, 2015 Wet....30 gallon garbage cans. best, ..................john How many glazes do you use? 5 glazes=150 gallon of material, 10 glazes=300 gallons. WOW. you continue to inspire us slow polks. Jed Link to comment Share on other sites More sharing options...
Celia UK Posted July 31, 2015 Report Share Posted July 31, 2015 Thanks Jed - if I see any differences when I test it'll be Interesting to match them with the theory. Link to comment Share on other sites More sharing options...
Guest JBaymore Posted August 1, 2015 Report Share Posted August 1, 2015 Wet....30 gallon garbage cans. best, ..................john How many glazes do you use? 5 glazes=150 gallon of material, 10 glazes=300 gallons. WOW. you continue to inspire us slow polks. Jed In the large volume sizes.... 9. Couple of small 5 gallon types also for some limited use stuff. The 30 gal cans are not dead full.... maybe kept at between 22 and 26 gallons in each. I find nothing worse to freedom and spontaneity than trying to glaze with limited material or space. I want to be able to pour, dip, trail and so on without "worrying". best, .................john Link to comment Share on other sites More sharing options...
Hulk Posted September 11, 2018 Report Share Posted September 11, 2018 "The water softener exchanges sodium for calcium. So soft water has extra fluxing power of sodium, albeit in very small amounts." I'm curious if rather hard water, softened (hence more sodium) could/would have significant impact of COE - crazing? Water here ~11 grains/gallon, hence mg sodium added per 8 oz glass of water 11 * 1.89 = 20.79 mg sodium* per 8oz glass of water. My first ever glaze mix crazed mightily! I might have made a mistake measuring up small (400g) batch. The liner ("functional clear" from school's lab - no luck getting the formula, yet) on the test tumblers did not craze, at all. I'll add silica on the next trial, and remove a small amount to mix with my tap water to compare against RO (or distilled via evap) water. I don't want to mention the formula just yet, as all indications - the source, glazy.org analysis and chart, GlazeMaster analysis and COE, my reading and very limited experiences - are the glaze ought'o fit better. *From Pure Water Products LLC website: "...sodium you'll have added to the final product. Although this is actually a rather complicated math problem, it can be simplified to the following: Grains per gallon (GPG) of total hardness x 1.89 = mg. of sodium (NA) in an 8 oz glass of water." Link to comment Share on other sites More sharing options...
Mark C. Posted September 11, 2018 Report Share Posted September 11, 2018 I would mix your glazes with unsoftened water. How about a hose tap near the water main? Link to comment Share on other sites More sharing options...
Callie Beller Diesel Posted September 11, 2018 Report Share Posted September 11, 2018 It takes 1000 mg to make one gram. 8 oz of water is about 236 ml Assuming your 400g batch of glaze contains 1/2 it’s weight again in water (200g), you have added somewhat less than .00189 of a gram of sodium to your glaze batch via your water. That quantity isn’t enough to make your glaze craze. You leave more than that in residue on the container you weigh out into. Unless you have unusually high levels of something like iron or lead in your water, using distilled water shouldn’t be necessary, and at that point you’re probably having to filter it to make it drinkable. You do occasionally hear of someone using rainwater, but that tends to be someone with no running water in their studio and a rain barrel outside. Link to comment Share on other sites More sharing options...
Hulk Posted September 11, 2018 Report Share Posted September 11, 2018 Thanks Mark, thanks Callie! I'll move ahead with simple addition of more silica, double checking the measurements, and side by side testing... Link to comment Share on other sites More sharing options...
Mark C. Posted September 11, 2018 Report Share Posted September 11, 2018 With this small of a batch mistakes can be very easy (might have made a mistake measuring up small (400g) batch.) Link to comment Share on other sites More sharing options...
Min Posted September 11, 2018 Report Share Posted September 11, 2018 4 hours ago, Hulk said: My first ever glaze mix crazed mightily! 9 minutes ago, Hulk said: I'll move ahead with simple addition of more silica If the crazing is bad, ie the craze lines are close together, adding silica probably won't fix it. There is only so much silica a glaze can take in, if the glaze already has a decent amount then chances are adding too much will result in some free silica that won't be part of the glaze melt. When that happens crazing actually gets worse. Finding a glaze with lower expansion fluxes is sometimes the solution. Link to comment Share on other sites More sharing options...
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