tomhumf Posted October 31, 2016 Report Share Posted October 31, 2016 I've recently been experimenting with layering glazes. I've been have trouble getting a nice glaze thickness and smoothness. When adding the second glaze it often has loads of tiny bubbles and goes on really thick. Should I be thinning the glazes out a lot more than if I'm doing single coats? They are currently around 40 specific gravity which has been about right for when just firing with one layer. I'm also not sure if the first coat should be bone dry before adding the second? I left it a day, but my garage is quite damp and cold. Thanks! Link to comment Share on other sites More sharing options...
High Bridge Pottery Posted October 31, 2016 Report Share Posted October 31, 2016 Try it straight away when the sheen has just gone from the first layer, it might work better instead of waiting for it to dry. Link to comment Share on other sites More sharing options...
neilestrick Posted November 1, 2016 Report Share Posted November 1, 2016 If you wait for the first layer to dry completely, the second layer will go on too thick. Dry glaze is much more porous than bisqued clay. Also, if the first layer is totally dry it will often lose its bond with the pot when it is rehydrated by the second layer. How dry the first layer needs to be depends on the glaze, but dry enough to handle is a good place to start. Link to comment Share on other sites More sharing options...
preeta Posted November 1, 2016 Report Share Posted November 1, 2016 AHA!!!!! that's why Warren MacKenzie does not wait to dip the second time in his documentary. thank you! thank you! THANK YOU to all 3 of you. you have helped me tremendously. Neil what you described is EXACTLY what happened to me this morning. I had to scrape off and start all over again. that takes care of the crazings that happen to some of my pots. yeah!!! Link to comment Share on other sites More sharing options...
Mark C. Posted November 1, 2016 Report Share Posted November 1, 2016 Put the second glaze on as soon as you can to the 1st one as noted above-if they both are wet they work better.I often use 4-5 glazes on the same pot as fast as I can get them on. Link to comment Share on other sites More sharing options...
tomhumf Posted November 1, 2016 Author Report Share Posted November 1, 2016 Oh wow, I'll try it later, never thought of doing it straight after. Thanks everyone Link to comment Share on other sites More sharing options...
tomhumf Posted November 1, 2016 Author Report Share Posted November 1, 2016 Oh, what about glaze thickness, do you use them more watery or just the same as single layer glazes? Link to comment Share on other sites More sharing options...
Mark C. Posted November 1, 2016 Report Share Posted November 1, 2016 all 15 of my glazes are the right thickness that is they are not watered down. One needs to know how they look with one another-a set of test tiles will aid you in this a lot. Glazes layered over one another or just a lip dip or next to one another-its all in a good set of test titles . Link to comment Share on other sites More sharing options...
neilestrick Posted November 1, 2016 Report Share Posted November 1, 2016 In my studio we do a 6 count for the first dip, 4 count for the second dip. Second dips must be at least an inch from the bottom to give the glazes room to run. For my work I use different rules so I can get the double dip all the way down to the bottom. I typically do a 4 count for the first dip, then just in and out for the second, staying 1/4 to 3/4 inch from the bottom, depending on the glaze combo and the size of the piece. As Mark said, make some test tiles that show how the glazes behave when layered. And remember that glaze A on glaze B will not look the same as glaze B on glaze A. I've got a board in my studio that shows the double dipping combos of all 14 class glazes, so 196 tiles. We're getting ready to redo it soon, as I've put 7 new glazes into use this week. It's a lot of work but well worth it. Link to comment Share on other sites More sharing options...
High Bridge Pottery Posted November 1, 2016 Report Share Posted November 1, 2016 Do you mean 140 (1.40) for surface gravity? I would say that is on the thin side already for dipping depending on ingredients in the glaze. Link to comment Share on other sites More sharing options...
tomhumf Posted November 1, 2016 Author Report Share Posted November 1, 2016 My hydrometer is labeled from 0 to 70. My glazes vary between 40 and 50 on my scale. 40 is about like skimmed milk so I guess it's just shorthand for 1.4 or 140 yes. I usually do about 3 or 4 second dip for one layer glazes, I bisque to ^06. I tried doing two layers tonight. The first trial was with the glazes my normal thickness. I thought this looked a bit thick so thinned them out a bit and did a second test. Looking at them now the first test looks better. I just waited until they were touch dry in both trials. I'm still seeing some little bubbling but not as bad as I've had previously. Link to comment Share on other sites More sharing options...
High Bridge Pottery Posted November 1, 2016 Report Share Posted November 1, 2016 I am always changing specific gravity for surface gravity I think that hydrometer is measuring in degrees baume but 40 does look to be 1.38 and 50 is 1.52 so close enough. Link to comment Share on other sites More sharing options...
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