Always used the finger method. Glad I'm not alone in this. Start adding too many sciencey gadget bits I drift off to la la land. Like to keep it simple ☺
Do yourself a favor and buy a graduated cylinder, weigh out 100ml of your glaze and then divide by 100 ( the weight of 100ml of water ). A specific gravity between 1.4 to 1.5 is a good place to start. Then test, test, test. This is such a quick, easy and cheap way to ensure you have a very reliable glaze.
Jonthepotter no problem! I know you mentioned these were non scientific ways of testing glazes, but I’ve been amazed at how much a few ounces of water can drastically change the outcome of a glaze.
Jon, I bought a couple of plastic veterinary 💉 syringes at my local farm store. They are 60 ml. So i weigh that thing and write down the weight. So after I stir my glaze well, I suck up glaze past 50 ml, then squirt out until it’s right at 50 ml. Weigh it again. Take the heavy weight and subtract the empty weight, then divide by 50. I agree with previous reply-I shoot for 1.4 or so. If it’s too heavy, I squirt it back in, add some water and stir and do it again. If you have an electronic kitchen scale from your local big box store and a simple calculator , it’s fast and easy. If I’m doing glaze testing and only mix up a small amount, sometimes I waste a lot when I use the graduated cylinder. And the plastic syringe is easy to clean. Love your videos!
Thanks for the video! I timed how long the matt white (which you said was the correct consistency) took to stop swirling and it was 2 seconds maybe 3. 8-10 seconds seems impossible.
Oh my gosh! FINALLY! Started working with out own glazes recently, and really was lost ..regarding thickness and consistency! Sooo happy you posted this video...and will have to look for your other glaze. Videos. What about jarred (premixed pints, etc) glazes? Same rules apply? I realize it varies on manufacturer, again, thanks again!
Hey @jonthepotter - this was geared towards dipping glazes, right?? if glazes are going to be used for painting on, then is there a rule of thumb about maybe a certain percentage thicker?? I know my Chun Plum is ALWAYS too thick - it usually looks about like mayo when I open the jar.
Hi, I have Q ! If I burn the pottery with glaze but under temperature that is need so it is safe to use for food?? I mean I use glaze need 1180 but I burn just 1000 that is ok!?
Hey Jon, I make my own black, matte white and floating blue, and I noticed that the blue and black tend to be thicker ( like chun plum) and don’t run, but my metallic green and butter cream which seem to be the more flowing glazes, tend to separate more and I’m able to use the methods for testing that you showed us. I think if a glaze has more clay in its recipe then it will be on the thicker side. I wish I had the recipes for the metallic green and buttercream! I would love to make those my self. I tested so many green recipes before just giving up and buying metallic green! I’m so in love with it! Thanks for all the tips!
Thanks Atalie! Those are great observations! I have made glazes in the past but for ease, convenience, and consistency I like to just but most of them!
Funny how you're wearing a mask in the thumbnail image and then stick your finger in the glaze 😆 there are a lot of dangerous ingredients in different glazes. Who cares about fertility issues, child deformity and SVHC's hahaha
I find the SG v useful but only after I’ve tested the glaze by checking thickness using a needle dragged through drying glaze. If the test is fine I check the SG so that I know optimum water content. An easy way is to use a small screw lid bottle half filled with nuts and bolts (cheaper than anything shop bought) float the bottle and draw a permanent marker line where it floats and mark the glaze number
hydrometer is my best most consistent way to test glaze thickness... Most of my glazes work perfectly at a reading of 1300 to 1600,,, each glaze is a bit different. I write the hydrometer reading on the glaze bucket. usually start with 8 oz. of water to each pound of dry glaze... add water as needed....Thanks for the videos! .
Appreciate the wealth of knowledge you are sharing. I am always learning how to work on getting the results I hope for in my pottery process. Keep it up!
Wow I love these tips so much. Thank you! I didn’t continue the ceramic class after my beginner level classes. So now I. Need to learn from you. Thanks!
Part II Great tutorial for all to consider.......your results speak volumes for your scientific methods. Is science not based on trial and research using the tools at hand? This is basic science to me. That being said I use brush on glazes at present and I am going to be doing my first SINGLE FIRE glaze firing with my next load(Cone 6 Stoneware Electric). Dipping glazes may be down the road, but with only 150 sq.ft. it would be a bit tight. Thanks again Jon......good video.
I've started playing with brushing on glaze vs dipping. It quickly has become apparent that judging thickness is an issue, especially with layering colors. I'm at a studio, so messing up the kiln shelves or ruining others' work is a huge no-no!
Thank you! I remember learning the dip way as well and couldn’t remember exactly. As I was doing research everyone is saying to use a DuPont viscosity cup... I knew that wasn’t the only way!
This might sound really amateur but I’m only just getting into pottery so, when you do multiple glaze layers of different colours like you do and as you say it’s too think and drips a lot, how do you know which glaze was the too thick one? Won’t it all drip together into each other? :)
i just stumbled on your channel and it's such a great change from all the uber technical approaches to glazing. I came to pottery late and terms like "specific gravity" freak me out lol. But i've been making art of various kinds my whole life...so just love your relaxed and experienced based way of explaining this. Like its art and actually NOT rocket science lol. So thanks for taking the stress out of this question for me.
Awesome video, thanks! You showed me a couple of new ways to test my glaze thickness. Thanks for doing a glazing series! I'd love to see you mixing your dry glaze with the water. Would love to hear your thoughts on if it's ok to use a glaze that you let sit for 6 months (does it need to be re-sieved?). How many times should a glaze be sieved before using it? And I'm sure much more. I've been a potter for 8 years. I've quite confident in glazing at the local studio and figuring out thickness (using their glazes that they've mixed up and they take care of). I've always fired at the local studio even though I have a full studio at home, with my own kiln. I'm soooooo afraid to do my first glaze load. I've done bisque. I've even bought and mixed up my glazes. Then let them sit for the past 6 months. EEEEEEK.
Really enjoyed this video, I've had a few issues, with the type of clay I'm glazing, like if the clay is more gritty like raku clay, is doesn't dry very fast, as it would if I was glazing stoneware, or college buff, seems I even need to triple or even quadruple the amount of dips into the glaze with the raku clay, smashing stuff as usual 👍
I find it endearing that your finger was glazed for the whole video! Ha ha! Also I really like the soft music in the background and your editing is spot on with removing any dead time while you are talking. I don’t do pottery but I love to watch you make it! Ha ha! But really I’m learning so much about video making from watching you! Thanks so much and keep on being awesome!
Thank you for this video! I just mixed my first dipping glaze. It's way too thick. When it dries it seems ok-ish. It's Celestial Blue from MN Co. I'm putting big cookie underneath and I'm just gonna send it. Have you used that glaze before? I can't wait to see it.
I had a feeling my glaze was too thick even though the specific gravity was right. I tried the drip test and got zero drips. I dipped two pieces at that thickness and will fire them, but I’m also going to add water until I get four to five drips, measure the specific gravity and try a few pieces at that thickness. I love your tips and hints. They are great for a new potter like me. Thanks for your videos!!
Excellent video, can't wait for the rest in this series. As a relatively new potter, I have found that the world of glazing is what confusing and secretive, not many openly give away tips and recipes. #earthnationceramics #simonleachpottery do. Do you use ready made or make up your own glazes?
Why not get glaze on your hand? At least the food-safe glazes and the like I've used I have been encouraged to stick my hand in to feel the consistency.
Even a glaze, that is considered "food safe", once fired, doesn't mean there isn't anything in it, that could potentially hurt you prior to that. Generally speaking, the base glaze recipe is pretty harmless, it's the colorants that can pose the problem. Some are heavy metals, which can lead to long term health problems. A little caution, like wearing latex gloves, never hurts (Unless you are allergic to latex). Though, I will say unless you have any open cuts or something of the like, on your hands, getting some glaze on them is not much of a concern.
Hi Jon this was very helpful, my glazes came out just a little too thin and I didn’t know what to do with them. So I will take the lids off and let them thicken up a bit. 👍🏽
Jonthepotter just realize that some of the glaze chemicals are soluble in the water (think about salt or sodium chloride) and even though the liquid is “clear” there will be some materials that you are removing with the liquid. You might consider finding a way to boil off the water from the part you pour off. Then see how much dry material remains in the pan and return that to the glaze bucket. If there’s enough to scrape out and return, it’s probably enough to affect the properties of the glaze. Probably best to not use your kitchen pans to do this. 😳
Hi Starcrossing, I am the same. The pottery is going really well and I am stoked with that part. Glazing is a whole different ball game. Just watched Jonthepotter's video and am going to the shed now to do all 5 tests! Wish me luck.🤞
this is awesome! as someone who is very interested in all things glazes - thank you. also, I am aware that you need a dust mask when mixing glazes but dry clay???? We need to wear a mask when its dry clay? humm? thanks in advance
Silica dust from the clay builds up in the lungs, as the body is unable to remove it. It can cause silicosis (hardening of the tissue of the lungs) and a large amount of other related issues, including tuberculosis, and possible auto immune diseases.
The first video of your that I watched was that really popular glazing video and I actually found it on my Pinterest feed. I don't know if you put that on Pinterest or who did, but I pin a lot of pottery stuff on there and it came up in my recommended feed. I clicked on it, it took me to RU-vid, I loved it, and I subscribed. :)