Glaze base quantity to mix

[Marilyn T]

To potters who only work with a few base glazes but with several colors: 

• Do you mix BIG buckets of the base glazes,  and then take out only enough for a small  bucket and add colorants to that?
• If so, do you keep your large bucket SG at equal water and dry materials so you can easily calculate amount of colorants to add, or ? 

Notes:  

• My goal is to cut down the # of large buckets I have, and to also decrease the # of times I am mixing full recipes.
•  I use 3 base glazes and 15 colors.  Some get more use than others.   I presently have 8 large buckets which is too many for the studio space I have.  
• I dip, pour, and spray glazes on my tableware.  Dipping is my preferred method.  I like to layer glazes which explains why I have so many colors.  
• My large buckets are Home Depot sized, and small buckets are Rona sized (3000 grams or .8 gallon).  
• I am a hobby potter so only produce a small amount of product.    

Your input is appreciated.   

 

[Hulk]

Hi Marilyn!

I'm still working each colour is a unique recipe; perhaps someday I'll look to simplify...

I'm using 2 gallon buckets for glaze, which is working well for me (so far); they aren't terribly expensive, there are several options available, and come with good lids. I'm keeping notes on specific gravity, thixotropic behaviour/adjustment, and results.

I'm finding the notes very helpful, and the two gallon size a good alternative for me - between the five gallon and 2.5 quart sizes - which stack well on my storage shelving, and I can handle easily (err, easier).

[Dick White]

I have done this when testing a single base glaze with multiple colorant oxides. For example, I wish to have some moderate sized containers, each having 500g of the original dry ingredients to which I could add whatever percent of colorant oxide. I will mix a large 5000g batch of glaze in the usual bucket with the usual amount of water and adjust it to an appropriate specific gravity. It will now be about 2.5 gallons of liquid. Then I will set out 10 empty containers and divide the glaze among the containers until all 10 of them have an equal amount of liquid glaze in them. Since they are all equally filled with an equally mixed liquid base glaze that originally was 5000g of dry materials, each of the smaller containers now has 1/10 of the original 5000g of dry materials, or 500g. Compute your colorant oxide percentages from there. Note that you do not have to add colorant oxides to all 10 containers right away. You can put a tight lid on a container and put it away somewhere out of your usual line of work, and use it later knowing that it still has 500g of original dry materials. You can adjust the math here to suit your needs.

[Marilyn T]

Hulk:  Good suggestion on the 2 gallon buckets.  I'll look for one and measure the height to make sure it fits on my shelves.  I will give more thought to Dick's suggestion and calculate what bucket size would work best.   

Dick:  I like your suggestion about measuring 5000g of the base glaze and separating it for storage in separate buckets.  That will save me time when measuring materials.  

If I do mix up a batch of dry ingredients in a large container do you think that a drill mixer would mix the ingredients sufficiently to ensure there is equal parts when separated into small buckets, or would the heavier materials sink to the bottom?  If not, I'd probably have to add water before separating the glaze into small portions. My preference for dry ingredients only, would be the lighter weight which I could fit on an available above-my-head shelf.  I'd then add colorants and water later.

[Dick White]

Without industrial mixing machinery, you can't mix dry materials to a sufficient equal consistency that the divided portions would be uniform. Wet mix and sieve it, then divide.

[oldlady]

marilyn, for a long time, i have been doing what you plan to do.   i mix a single base glaze to a 6 or 8000 gram batch and mix the dry ingredients using a heavy duty drywall mud mixer.   i do not add water until i decide what colors i plan to use.   the 2 1/2 gallon buckets are from grocery store bakeries.   they have 2 sizes available free if you ask for them.  and ask for the lids, some folks use the buckets for washing cars and don't ask for lids.   the icing bucket size is my favorite for colors other than green.   nearly everything i make is green but the base recipe takes all the colors i have in mason stains.  

if the first supermarket says no, ask a different brand store.   the bakery managers i know are very happy to get the buckets out of their workspace without putting them in the trash.  one has even decided to put them outside the store so people can pick them up at the curb.   another one says they use the buckets in their deli section so i cannot have them.  why pay for what is free when there are so many things you would really like to have?   if i save money on buckets, i can buy another color stain.

i combine the ingredients in the bucket as i add them.  first two or three depending on the amount, add the lid and shake and roll the bucket.   add more, do the same.  once all of them are weighed, i mix all of them with a very large Jiffy mixer.  it has a half inch diameter shaft and   is about 2 feet long.  i have cut a hole in the center of  a large bucket lid and put the jiffy mixer shaft up through the hole that is just a little bigger than the shaft.  i take the bucket outside, use my respirator and mix the whole thing together.   rolling the bucket in the grass helps distribute the powders very well before i use  the mixer.  WITH THE LID TIGHTLY ON!

then it is just a matter of keeping track of how much you use out of the large bucket.  if you know you will need 3000 grams of blue and you are already down to 4000 grams, it might be time to mix some more.  i use distilled water because it is always constant.  you should see the color of the birdbath  that uses tap water!  it started out white and now, years later, i cannot get the red out.

[Marilyn T]

OldLady:   Thanks for your advice on mixing dry ingredients and where to source buckets.  I will keep my eyes open. Good advice to use a drywall mixer to mix the dry ingredients in a 6-8K gram batch, as I frequently find pockets of the same material when I try to mix it with a spatula.  

Dick:  I agree that getting a homogeneous mixture of a large amount of dry material (e.g. 1/2 garbage pail size) would be a concern, so I am leaning towards adding water to it to create a reservoir to top up my smaller coloured buckets (size yet undetermined).  Sieving it on a regular basis might cause me to rethink the reservoir size from 1/2 garbage can to 5 gal. Thanks.  Your input was very helpful.