Jump to content

Suspenders/binders In Speedball Glazes?


enbarro

Recommended Posts

Hi, off all the commercial glazes, I’ve tried speedball glazes are the ones that I like the best for brushing.

I remember a similar smell on the non-toxic glue sticks I used as a kid in the early 80’s. I bought several brands of glue sticks but smell different…

Anyone care to venture a guess as to what kind of suspenders/binders speedball uses?

If I could fine tune my low fire fritted glazes to brush like speedball’s I’d save a lot of money, plus I rather sell functional ware I know every single ingredient in the glazes used… I’ve tried cmc and bentonite but I don’t like the results. I like gerstley borate, but eliminating it would give me more freedom to formulate the glazes I’m looking for...

Any help/advice will be greatly appreciated.

Link to comment
Share on other sites

I've never used Speedball Earthenware (low-fire) or Stoneware (high-fire) glazes.

 

Neither MSDS gives even a hint at what they contain, except they're "safe". 

 

Stoneware Glaze:  www.speedballart.com/cms_wfc/uploads/53.pdf

Earthenware Glaze:  www.speedballart.com/cms_wfc/uploads/277.pdf

 

I'm not aware of any inorganic ceramic product which has a smell, so they either add a fragrance to their glaze, or some organic plastic binder which has a smell you've experienced in other products.

 

I have rarely seen MSDS sheets like this:  http://www.speedballart.com/msds.php

 

They tell you absolutely nothing.  Some chemical in their Brush Shaper "smells pleasant".  What-ever-it-is has vapor pressure less than Butyl Acetate - really? That's essentially useless information.

 

John Baymore and I have both added a little polyvinyl acetate as a brushing and hardening medium on occasion.  Most know this as Elmer's White Glue.

 

Hi, off all the commercial glazes, I’ve tried speedball glazes are the ones that I like the best for brushing.

I remember a similar smell on the non-toxic glue sticks I used as a kid in the early 80’s. I bought several brands of glue sticks but smell different…

Anyone care to venture a guess as to what kind of suspenders/binders speedball uses?

If I could fine tune my low fire fritted glazes to brush like speedball’s I’d save a lot of money, plus I rather sell functional ware I know every single ingredient in the glazes used… I’ve tried cmc and bentonite but I don’t like the results. I like gerstley borate, but eliminating it would give me more freedom to formulate the glazes I’m looking for...

Any help/advice will be greatly appreciated.

Link to comment
Share on other sites

Guest JBaymore

Norm,

 

I've seen tons of MSDSs that are basically useless smokescreens.

 

While the manufacturers / suppliers are supposed to fill out the forms completely (for obvious reasons), there is no regulatory body with "teeth" actually reviewing them.  So some are nigh on to useless.

 

Which is bad for the folks that dcan't look at the sheet and see that it is a whitewashing job.

 

My favorite is the "its safe" kind of thing on something that containes finely ground flint.  Yeah, it is safe........ when it is WET.  That is the kind of technicalities they often try to play. 

 

Years ago I had a health issue from using lusters (final working diagnosis... that was the source of the problem).  The carriers from the particular supplier were listed as something like "organic hydrocarbons".  Long story short, my doctors (and I) would have needed a bevy of lawyers to pry WHAT exact stuff those were.  We gave up.

 

The "stock" bevy of usual suspenders / binders / brushing consistency additives for water based are ball clays, CMC, bentonite, hectorite, macaloid, gum arabic, gum tragecanth, polyvinyl acetate, propelyne glycol, glycerine, green tea extract, and various Ph adjusters for the water chemistry.  And formaldehyde or other mold inhibitors to keep the organic additives from "growing". 

 

best,

 

.........................john

Link to comment
Share on other sites

The smell from brushing glazes is the biocide used to keep the gum solution in the glaze from getting eaten up by bacteria. In the old days it was formaldehyde, now there are numerous types of biocides on the market. I can't remember the name of the one we used when I was a tech for a clay/glaze supplier. The stuff is not necessarily 'safe' on its own (it's a biocide, after all), but there's a small enough amount in the glaze to allow for the 'Non Toxic' labeling.

 

To make your own glazes brush well, first add 2% Vee-Gum T to the mix. You need to blunge this well with water before adding it. A stick blender works well. Then substitute about 1/3 of the water with a gum solution. You'll need to tweak this till you get the brushability you want. To make the gum solution, add 2 tablespoons CMC gum to 1 gallon of water. Let it sit overnight and then blend well till it's smooth. Also add in 1/4 teaspoon copper carbonate to act as a preservative. I know you said you didn't like CMC gum, but with the Vee-Gum T it really does make a nice brushing mix. But like I said, you'll have to figure out just how much gum solution you like. The feel of the glaze will vary greatly depending on how much you use. If you've been using it in combination with Gerstley glazes, then the balance was probably out of whack.

 

Stop using Gerstley and start using a substitution frit like Gillespie Borate. It's far more consistent in formula and it won't run out like Gerstley. I have found that the Gillespie is a stronger flux than Gerstley, so some testing will be needed.

Link to comment
Share on other sites

I'd initially try adding 1% of Elmers Glue by weight to get used to the effect PVA has.  I'd suggest diluting the glue with water first as it takes some stirring to incorporate the water.  But too much much agitation can create foaming.

 

The Achilles heel of PVA is a glaze with too much free soluble boron cross-links the PVA and it becomes becomes lumpy and not useful.  So test mixing some white glue with a small amount of glaze and check back a while later and give it a stir to assure yourself that globs have not formed.

 

Unless you encounter this problem, a small amount of PVA definitely help keep the glaze where you put it. 

 

We use propylene glycol as a a brushing medium to provide a smoother application.

 

How much Elmer’s glue should I add per volume of glaze?

Link to comment
Share on other sites

Guest JBaymore

Remember that once you add Elmers.... the glaze will tend to "set up" in the containers if they are left open to the air. Meaning it will tend to "glue" itself to the sides where it gets splashed on there. Once dry, it does not go back into suspension like the plain vanilla dry powder did for that glaze. Brushes left out to dry w ill be harder to clean, etc.

 

So........ like most things....... there is a trade off.

 

best,

 

.......................john

Link to comment
Share on other sites

 

To make your own glazes brush well, first add 2% Vee-Gum T to the mix. You need to blunge this well with water before adding it.

One trick I have learned that helps get gums into suspension is to add alcohol at about three times the weight of the gum and let it sit a minute, then add water and stir. The alcohol helps the gum solublize much more quickly and without the clumping you usually get. It also might hold down the bacterial growtrh a little.

Link to comment
Share on other sites

Thanks! I’m going to try a few drops of Elmer’s in an ounce of glaze and see what happens. I’m ok with mixing in the glue just before glazing.

Does the Gillespie borate gel glazes like Gerstely? That’s the main reason I use Gerstley. The other is that I get a clean sgraffito line.

Neilestrick, why do you prefer Veegum t for brushing and bentonite just for suspending? I originally thought Veegum was a whiter type of bentonite…

Link to comment
Share on other sites

For brushing glazes I just like the Veegum better. There are differences in the way they feel when brushing. Veegum is pretty expensive to use for suspending. You won't be able to tell the difference between it and plain old bentonite in that application.

 

Veegum T is also wonderful in porcelain bodies.

Link to comment
Share on other sites

Gillespie Borate does not gel. It's simply a frit/blend formulated to the same chemistry as Gerstley. It does not necessarily work as a 100% perfect direct substitute to Gerstley for a couple of reasons. First, due to the extreme variation in the Gerstley mine over the years, there's not one formula for it. So the formula Gillespie settled on for their frit may or may not match the chemistry of the Gerstley you've been using. Second, Gerstley is not a single mineral. It is a conglomeration of minerals, so will therefore behave and melt a bit differently than any substitute. Gillespie tends to work well in most glaze recipes, however testing and possibly tweaking will of course be necessary.

Link to comment
Share on other sites

I

 

The smell from brushing glazes is the biocide used to keep the gum solution in the glaze from getting eaten up by bacteria. In the old days it was formaldehyde, now there are numerous types of biocides on the market. I can't remember the name of the one we used when I was a tech for a clay/glaze supplier. The stuff is not necessarily 'safe' on its own (it's a biocide, after all), but there's a small enough amount in the glaze to allow for the 'Non Toxic' labeling.

 

To make your own glazes brush well, first add 2% Vee-Gum T to the mix. You need to blunge this well with water before adding it. A stick blender works well. Then substitute about 1/3 of the water with a gum solution. You'll need to tweak this till you get the brushability you want. To make the gum solution, add 2 tablespoons CMC gum to 1 gallon of water. Let it sit overnight and then blend well till it's smooth. Also add in 1/4 teaspoon copper carbonate to act as a preservative. I know you said you didn't like CMC gum, but with the Vee-Gum T it really does make a nice brushing mix. But like I said, you'll have to figure out just how much gum solution you like. The feel of the glaze will vary greatly depending on how much you use. If you've been using it in combination with Gerstley glazes, then the balance was probably out of whack.

 

Stop using Gerstley and start using a substitution frit like Gillespie Borate. It's far more consistent in formula and it won't run out like Gerstley. I have found that the Gillespie is a stronger flux than Gerstley, so some testing will be needed.

Neil, I was told to cook the CMC mix prior to diluting and mixing with glaze/stain. Is there any need for this?

Link to comment
Share on other sites

When I am brush colors on unfired majolica glazes I often use a few drops of glycerin, which gives me a brush stroke more like ink on paper.  I don't know why it wouldn't work in glaze with some experimentation.

Prob. lots more expensive.

Link to comment
Share on other sites

I

 

The smell from brushing glazes is the biocide used to keep the gum solution in the glaze from getting eaten up by bacteria. In the old days it was formaldehyde, now there are numerous types of biocides on the market. I can't remember the name of the one we used when I was a tech for a clay/glaze supplier. The stuff is not necessarily 'safe' on its own (it's a biocide, after all), but there's a small enough amount in the glaze to allow for the 'Non Toxic' labeling.

 

To make your own glazes brush well, first add 2% Vee-Gum T to the mix. You need to blunge this well with water before adding it. A stick blender works well. Then substitute about 1/3 of the water with a gum solution. You'll need to tweak this till you get the brushability you want. To make the gum solution, add 2 tablespoons CMC gum to 1 gallon of water. Let it sit overnight and then blend well till it's smooth. Also add in 1/4 teaspoon copper carbonate to act as a preservative. I know you said you didn't like CMC gum, but with the Vee-Gum T it really does make a nice brushing mix. But like I said, you'll have to figure out just how much gum solution you like. The feel of the glaze will vary greatly depending on how much you use. If you've been using it in combination with Gerstley glazes, then the balance was probably out of whack.

 

Stop using Gerstley and start using a substitution frit like Gillespie Borate. It's far more consistent in formula and it won't run out like Gerstley. I have found that the Gillespie is a stronger flux than Gerstley, so some testing will be needed.

Neil, I was told to cook the CMC mix prior to diluting and mixing with glaze/stain. Is there any need for this?

 

Literally cook it with heat? Bake it dry or boil it? I could see how boiling it might make it go into solution faster, as hot water works faster than cold water. But if you just let it sit overnight then blend, it comes out fine.

 

I have heard of the alcohol trick Bob mentioned, but have never tried it.

Link to comment
Share on other sites

CMC (carboxymethylcellulose) like Bentonite hydrates much faster in hot water than cold - I use a microwave to heat the water.

 

 

Xanthan Gum hydrates readily in cold water and has 100-fold more powerful suspension ability, than CMC or Guar Gum.  As a consequence Xanthan Gum is far less costly to use.

 

But the most desirable quality is its loss of "syrupy factor" under pressure.  

 

When used in a sprayer, or when poured, Xanthan Gum instantly loses its viscosity - so no clogs or drips.  But the moment it's applied to bisque, whether sprayed, dipped, or hand-painted, no longer under pressure Xanthan gum instantly gels again.

 

Once fully hydrated, CMC and Xanthan Gum together cross-link creating a combination property.  Industry makes extensive use of mixed gums.  http://projekt.sik.se/nrs/Open_transactions/2008/Oral%20presentations/Rheology%20of%20Food%20Hydrocolloids/Tipvarakarnkoon.pdf

med_gallery_18533_676_12538.jpg

http://www.adm.com/en-US/products/Documents/ADM-Europe-What-is-Xanthan-Gum.pdf

 

I

 

Neil, I was told to cook the CMC mix prior to diluting and mixing with glaze/stain. Is there any need for this?

 
Link to comment
Share on other sites

As I have posted earlier, I have a bag of GB that is from maybe 15 years ago when I first could afford to put an inventory of materials in. After a year or so decided to base more in the frits and other materials. I find it interesting that a lot of glazes still list GB as a component even though it has proven inconsistent in results.

Link to comment
Share on other sites

Norm, you've just pointed out one of my other issues with many Gerstley glazes- they rely on it too heavily as a suspension agent. And when there's a problem with the Gerstley, or they find themselves running out in their studio one day because they forgot to buy more, they not only have to deal with replacing the boron, but also with keeping it in suspension. Relying on one ingredient so heavily in a glaze, for formula and for suspension, is not a smart way to formulate a glaze in my opinion. If EPK ever runs out I can easily find another clay to put in the formula to keep it in suspension.

 

I really don't think anyone on this forum cares who is selling the Gerstley. If my mom was selling it I still wouldn't use it. So again, how about backing off on the personal attacks? This is simply an exchange of ideas. And I think we're getting tons of great info out there for every one to read. Keep it civil.

 

Gillespie Borate is the same price as most frits, so I'm surprised you keep bringing up the cost as an issue since so many of glazes you've talked about on the forum have frits in them.

 

I'm done with this thread, too.

Link to comment
Share on other sites

Guest JBaymore

I am (unfortunately) locking this thread since it has deteriorated in non-productive manner and is no longer carrying the spirit of the helpful and courteous Ceramic Arts Daily atmosphere we wish to promote here. 

 

I can assure you that the Mods and Admins are looking into this matter, as to how we arrived at this place.

 

best,

 

.................john

 

CAD Forums Moderator

Link to comment
Share on other sites

Archived

This topic is now archived and is closed to further replies.

×
×
  • Create New...

Important Information

By using this site, you agree to our Terms of Use.