Bam2015

Ain't that the truth Pres? I do the same thing, hurry up and get to the finish line. Gazal, I am not inferring that you were racing to the finish line, that was just a little self-reflection. But, it will be interesting to find out what the problem was. I hope you will keep us posted. Betty

Min, thank you for sharing the video link, great stuff! Flahbacks to being a student in Gen Chem! Callie, thank you for the comparison of the glaze mixing classes. I am also in the process of deciding which one to take, so good to have that info. Pyewackette, I hope you will let us know which class you decide to take, and let us know how it goes. Best, Betty

Min, thank you for your thoughtful response, great info to have. I am going to start mixing & testing my own clears and have Britt's book, so I will start there. I am just starting to understand the chemistry behind this. Over the past year I have spent my time focusing on throwing skills. I see that I need to expand my knowledge and learn about glaze fits. Betty

Hi All, I said I would share the clear glaze recipe when I got it. Here it is from the studio who mixed it for me. EP Kaolin 20.00 Ferro Frit 3134 20.00 G-200 Feldspar 20.00 Silica 19.00 Wollastonite 15.00 Talc 6.00 It's also on this website. https://glazy.org/recipes/6798 Any thoughts on how to adjust this recipe to reduce crazing is appreciated. Betty

Thank you for the suggestion Pres. I will let you know if I try that recipe. Right now I am waiting for the recipe for the clear that is crazing. I'll post it on Mon when I get it. Betty

Thank you Min. I will heed your advice and appreciate you taking the time to thoughtfully respond to my post. I asked the studio if they would share their recipe and if they do, I'll post it, otherwise I will start from scratch with some of John Britt's recipes. Betty

Min, I am going to ask them for the recipe and if they provide it, I'll share. I doubt it's a recipe that they developed on their own. Although I pulled out some pieces that I previously fired which crazed, I also have several pieces from when I first bought the glaze that did not craze. So maybe it just needed to be thinned? I'll do some testing now that I have thinned it a bit.

Callie, I pulled out some pieces that I made a few months ago, same clay bodies & same clear glaze. I now see crazing on those as well. I guess it just didn't happen initially. I guess it's time for me to take another glazing workshop and start making my own glazes with testing, testing and more testing. Thank you for the input.

Min & Dick, thank you for your responses. Yes,Orton witness cones on each shelf. The cones indicated proper firing. Dick, I just measured the SG using the method you indicated. I read a number of articles against using a hydrometer. The SG was a bit high, so I added water. I'll see if that helped. Oh well, what a bummer! Was hoping for an easy fix and maybe thinning it will help. I guess I should I just start mixing my own glaze(s)? I just want a clear glaze, I use a lot of underglazes and mason stains. Just when you think you finally have things figure out.

Morning All! I know that crazing has been covered in a number of threads, but not sure the questions I am about to ask have been addressed. I have been using the same clear glaze with success for several kiln loads on both Laguna #15 cone 6 porcelain and Laguna #65 stoneware clay with success (no crazing), but this last load crazed, both the porcelain and stoneware. I did not mix the glaze, I purchased it from a pottery studio where I used to be a member, they mixed up a batch for me. I'm wondering if the following can help to reduce the risk of crazing: 1) Thin the glaze a little with water? I don't have any glaze making chemicals to add to fix this problem nor do I own a hydrometer, but I could buy one. 2) Does glazing the inside of the pot and not glazing the outside reduce risk of glazing? 3) Does bisque temp/cone make a difference? I think I had one more thought, but it's left my brain. Thank you in advance. To those forum members in Ian's path I hope you're ok. I just edited my post because I first said that I don't want to mix my own clear glaze, but if that's the answer then why not? Betty

Quite impressive!

In the past I tolerated poor customer service from a local supplier because they are nearby. Thankfully they have gotten better over the past couple of years.

Hi All, As I was painting underglaze on greenware pots today, I started thinking about how underglaze affects pottery seams like mug handles. So here is my question, does underglaze have a negative, positive, or no affect on greenware pottery seams/joints? In other words, does added moisture from the underglaze affect drying and potentially cause the seam to open up? Or does it help to seal a seam? Or maybe the affect is neutral. I know that one or more of you know the answer. Thank you, Betty

Neil, I already tossed them. But thank you for offering to take a look at them. Betty

Thanks Neil. That's what I assumed but last time I did a glaze fire, most of my little porcelain bowls cracked on the bottom and I had shut my kiln switch off after the firing was complete. So I was wondering if I made the kiln cool too quickly and that caused the cracks. I've used porcelain in the past without this problem. This time I dried them pretty quickly, I treated them like stoneware, so maybe that was the problem. Betty

I feel a bit stupid asking this question, but here goes. Does a kiln go through a cooling down program after firing or does it just switch off? Betty

Lee, that's a beautiful piece! I hope you will share the final results with us. I listen to audiobooks, I'm addicted! I renewed my library card during the pandemic and stopped buy ebooks and audiobooks. Extra $$ to spend on clay. Betty

GLR, what do you have the roller set on with your first pass through and then how much do you change the setting? I'm asking because I find that if I don't make multiple pass throughs and only change the setting slightly then the clay then it sometimes buckles on itself and cracks. I hope that made sense. I also change the orientation of the clay each time I pass it through the rollers. Betty

Min, I brushed the outside of the pots in underglaze (no CMC mixed in). I then added designs using stencils. In the stenciled areas I used Mason stains mixed with CMC. I used the CMC thicken the Mason stain mix so it would be less likely to seep under the edges of the stencils. I hope that made sense. Sorry if I confused anyone. Betty

Bill, I used the 'slow glaze' program and fired to cone 6 in my L & L kiln. I like to keep things simple. Betty

Hi All, I said that I would report back after I single fired pots with CMC in the mason stain mix. The glaze seemed to resist some areas where I used the CMC/Mason stain mix. If I am using underglazes or mason stains with CMC added, then I won't be single firing. Sorry, no pics to share, busy working at my paying job. Betty

Neil, thank you for chiming in. Your responses are always spot on. Old Lady, I will share results.

Here's a thought, if the styrofoam isn't smooth then the roughness might show up in the mold. But I've only made a few plaster molds, so I'm just guessing. Betty

Ok, gotcha Dick. I'll just fire away and see what happens to the single fire with the CMC. Betty

Dick, thank you for your response. My concern is the CMC in my underglaze with the single firing. Doesn't CMC burn out? And if so, how will that affect the clear glossy glaze that I put over it? Maybe I just have to start my kiln and see what happens. What do you mean when you say it is the clay body that I have to worry about? Betty