Thinning a Commercial Brush Glaze

[Benzine]

My Art Club students are glazing dozens of the same form, for one of our projects.  I was initially going to use one of our dip glazes, but don't think we have enough, nor do I think I have enough time to order more of it.  So I do have quite a bit of another color that will work, but it is a brush on glaze.  The instructions say that it can be thinned for dipping or pouring, but don't specify how much I would want to thin it.  For dip glazes I've always gone with the "Heavy Cream" consistency (What's a hydrometer?), but I wasn't sure if that's the consistency I would want for something that is normally brush on.  My concern arises from the fact that I know that commercially made, bottled glazes, that are meant for brushing, have additives that make them easier to brush, like gum. 

Anyone have any experience/ suggestions on this?

[Pres]

In the past, I have watered down brush on glazes with water. My final consistency was the same as a dip glaze that I would make up. I checked this by dipping my hand in the glaze and checking the layer. . . if cuticles were hidden it was too thick, thin a little more, when the layer was thin enough to cover the cuticles but show them then it was Ok. Then I would test tile it, dipping one coat, then a second coat on part of it tile. This allowed me to check the next firing and begin to use the glaze.

 

best,

Pres

[neilestrick]

Brushing glazes have a higher water content than dipping glazes. That is part of what makes them flow nicely with a brush, and why you need 3 coats. If you thin a brushing glaze down to where it is fluid enough to dip, you'll have a glaze that has a really high water content compared to a normal dipping glaze. So when you dip it, you won't get as much actual glaze material on the pot as a normal dipping glaze dipped for the same length of time. You can dip longer, but the pot will quickly become saturated by all the extra water. So you'll probably have to dip twice. Your best bet is to only thin is a much as is needed to get it to apply nicely, which may not be as thin as your normal dipping glaze.

[Benzine]

What if I added a deflocculant?  That way it would flow easier, but the water content would be the same.

[NancyAmores]

Thanks to a post here by Pres a couple of years ago I started dipping in commercial glazes and it worked great, with a few adjustments the glazes look better than when brushed. If you're using Coyote, Laguna, Georgies, they'll dry really quick like a dipping glaze would, they don't seem to have a lot of gum added. Amaco, Mayco, Duncan take longer to dry but work. With those ones I'll let the drips roll off and just as the top starts to dry turn it over and let the glaze head towards the top again. Mostly just need some water added until it flows nicely over the piece and into texture. I've been trying Darvan 7 in the last couple of batches after seeing John Britt's vid on flocc and deflocc, but after reading a post on the forums last week about it may have to re-think that decision and just stick to water. You might want to test dip a few small pieces before the larger ones to see how the glaze flows. Like a regular dipping glaze you'll have to dip the inside/outside separately or the piece gets waterlogged. I sometimes have to heat the pieces a bit, and keep the glaze at room temp or once again, they'll take forever to dry.

[oldlady]

one of our members, chris throws pots, has a video on his website showing how he uses a brush, a giffin grip and glaze to get a beautiful interior on large bowls.  maybe we can convince him to say more.

[Benzine]

Thanks for the suggestions all.  I'll mix up some different batches, and give them some testing, before using them, on the wares.

I also need to do my best, to make the glazing "Student Proof".  Not all my Art Club, have experience with clay and glaze work, as some haven't taken that class with me.  Even those, that have still struggled with the making of our wares.  I tried to initially do pulled handles, but there wasn't a lot of consistency.  Soooo, ended up making an extruder die, and life got easier...

[Pres]

Ben,

You have probably read how I pulled  ribbed ribbon handles for all of my pots. My mug handles have gotten poor definition of the ribs due to extreme arthritis of the rt thumb as it now has no cartilage between the end and next bone . At NCECA this year I picked up a hand extruder, and die set for handles. Using a dremel, I modified one of the handle dies to replicate the handles I used to pull. I have just finished up a grouping of 60 mugs using these new handles and find that there is little to be seen different between the pulled and the extruded. I do miss the taper that the pulled had from top to bottom, but find I can live without it. I really did not know what to do until this solution, and I have been having trouble training my Lt had to pull handles.

 

 

best,

Pres

[Benzine]

Dang lazy, non-dominant hands!

I too like the taper of pulled handles.  I will continue using them, for my own work.   I really do like the look of those that we extruded though.  I just made the die with a drill and scroll saw.

[Pres]

I am going to try "pulling" some of the extruded handles to see if they will hold to it. I still pull large handles for pitchers and other things where the wider furrow in the center or edges does not matter. However, these extruded ones look pretty good, I will post pics when I have them bisqued and later glazed.

 

best,

Pres

[Benzine]

I remember Mark stating, that he believed that extruded handles were actually stronger, as they are being compressed, while being made, as opposed to stretched out, with a pulled handle. 

I wonder if anyone has experimented with this, to determine the difference in strength?

[Benzine]

Thought I'd post an update.

The thinned glaze turned out great.  It actually looked better than it normally does, brushed on from the bottle, where it generally seems too thin even with the correct amount of coats applied.  I may have to keep a dipping bucket of it around, for when something similar comes up.

I am glad it did turn out well, as we used them on teacher/ staff mugs, in honor of Teacher Appreciation Day/ Week.  We made about 90 of them (You don't realize how many coworkers you actually have until you do something like this).  The Staff was very appreciative. 

[Pres]

Ben,

Great that the glazing worked out well, and that it was so much easier to dip glaze the #'s you were doing rather than painting on. I think in the long run the dipping works better all around. I especially like to do double dips with thinned dipping glaze.

On another note, I have just posted some pictures of the mugs with the extruded handles. Most around here, don't know the difference. I found them quicker in some ways, but have to be careful with the clay consistency. I finish by filling bottom gap as it attaches to the mug at the base, and also with knobs at the top attachment. They seem to be pretty sturdy and I will be using them from now on. Still pulling larger handles for pitchers and other large forms.

 

best,

Pres

[Rae Reich]

On 4/23/2018 at 6:29 AM, Benzine said:

I remember Mark stating, that he believed that extruded handles were actually stronger, as they are being compressed, while being made, as opposed to stretched out, with a pulled handle. 

I wonder if anyone has experimented with this, to determine the difference in strength?

Since the plate-shaped clay molecules are brought into alignment and more strength by the rotational nature of pug mills, wedging, centering, etc, then it would seem that pulled handles would be at least marginally stronger during the forming process (bend a freshly extruded handle and a pulled one to breaking point).

After firing - not so sure, handles are fragile anyway. I would think that compressed, extruded handles are stronger than slip-cast handles. 

[DirtRoads]

On 4/20/2018 at 4:58 PM, Pres said:

In the past, I have watered down brush on glazes with water. My final consistency was the same as a dip glaze that I would make up. I checked this by dipping my hand in the glaze and checking the layer. . . if cuticles were hidden it was too thick, thin a little more, when the layer was thin enough to cover the cuticles but show them then it was Ok. Then I would test tile it, dipping one coat, then a second coat on part of it tile. This allowed me to check the next firing and begin to use the glaze.

 

best,

Pres

I didn't know about the cuticle test.  We have been having problems with glazes this year because I have two new glazers.  They couldn't grip the "whole milk, etc. concept".    The cuticle test has been working really well.    Thank you.  (I've never gotten a hydrometer to work because we don't have large enough buckets of glaze and I haven't found a small one)