Mastering Glaze Consistency
What if glazing felt like the most satisfying part of making pottery?
When you understand your glazes, the guessing stops. You know what you're doing at every step, and opening the kiln stops feeling unpredictable.
MGC gives you the step-by-step process to get there.
You're not alone if any of these sound familiar...
These things happen to every potter, including myself.
- Unexpected running onto the kiln shelves
- Cracking and peeling before the firing
- A crawling glaze that left patches of bare clay
- A cloudy clear glaze
- A glaze that turned out the wrong colour (floating blues, anyone?)
- A glaze that's rough on rims but fine everywhere else
- A glaze that takes forever to dry, making layering and handling difficult
- A glaze that's too powdery and comes off on your fingers
- Drips and tong marks that don't blend in
An example of a glaze crawling
What did you do to try to solve these issues?
Did you just want to sit on the floor, give up, blame the kiln gods and wonder why you're even still doing this?
Maybe you went to a Facebook group or Reddit or some other forum, hoping someone has already asked the question because you feel like you are too experienced and embarrassed to be asking these kinds of questions. You might feel nervous to talk about it because you don't have the correct vocabulary and might say something inaccurate. What if other potters judge you? You hate that you haven't been able to figure it out.
Perhaps you've asked your trusted potter friends or a local teacher and it feels like you've gotten a mishmash of advice - some helpful, some giving you more questions than answers. This can leave you feeling more confused and nervous about making a big mistake.
You might be thinking:
"Why can't I get it right?"
"What am I doing wrong?"
"Am I the only one going through this?"
"Will it always be this hard and frustrating?"
If any of this feels familiar...
Then you are just like the rest of us!
Every potter I have talked to experiences glaze issues, even those who have been doing it for decades.
You put so much effort into making pots and you think you've finally got your glazing process down, just to have another disappointing kiln opening.
You put your heart and soul into your pottery, only for it to be ruined in the glaze firing. Even though you focus on glazing consistently, your results are anything but consistent.
Here's the truth
There's no one answer to any glaze problem. Context matters. There are many factors that determine the next right step to solving a glaze problem.
If you're asking glaze advice from someone and they haven't asked you a series of important questions about:
- your glazing process
- your glaze recipe
- the water content of your glaze
- your clay body
- your firing schedule
- your witness cones
- the size of your kiln
- your cooling cycle
Then they might not have enough information to give you accurate advice. They are likely giving you advice based on their experience with their glazes. Unless you're creating identical pieces, or they're a glaze teacher who has helped countless potters with countless glazes, their well-intentioned advice might not be relevant to your situation.
That's a lot of factors. And when something goes wrong, it can feel impossible to know where to start.
You just need a process
When we can be systematic about all of the important factors that are contributing to our glaze results and ensure consistency with each step, we will improve our results and become capable of repeating our most exciting glaze results, firing after firing.
I have a step-by-step process that will ensure you're paying attention to all the right things and not leaving anything out.
You don't even need a background in science to do this.
It's just going to take a bit of testing, experimenting and note taking to create a glazing system that works for you and your glazes. Putting in this initial work is going to help you with every glaze you use for the rest of your pottery career.
Achieve consistently stunning glaze results every time you fire AND know exactly what to do to control undesired outcomes like colour and surface flaws.
Introducing:
A step-by-step program for potters who are ready to stop guessing and start understanding their glazes.
You'll go through every factor that affects your glaze results, learn why things go wrong, and build a testing system you can use with your own glazes, in your own studio, at any temperature.
No chemistry background required. Just curiosity, some test tiles, and a willingness to pay attention to things you might not have paid attention to before.
This course is for you if:
- You're a professional potter and glaze inconsistencies are costing you time, materials, and pieces you can't sell
- You're a dedicated hobbyist with your own studio and glazes you want to get under control
- You're a pottery teacher who wants a deeper understanding of the glazes your students are using
- You're running a community studio or the one responsible for keeping glazes in good shape
- You're a guild or co-op member who wants to help improve the studio's glaze buckets
- You're tired of inconsistent results and ready to actually do something about it
Not sure if this is the right fit for you? Send me an email at support@suemcleodceramics.com and I'm happy to help you figure out the best next step.
This course is probably not for you if:
- You work exclusively in a community studio where you can't bring your own glazes and you can't add water or make any adjustments to the studio glazes
- You have little to no experience with glazing
By the end of Mastering Glaze Consistency, you'll:
- Understand why your glazes are behaving the way they are, and know what to do about it
- Have a repeatable process for testing and adjusting your glazes so you're not starting from scratch every time something goes wrong
- Be able to troubleshoot glaze problems systematically instead of searching the internet and getting conflicting advice
- Feel confident glazing your pieces instead of dreading it or putting it off
- Stop wasting time, materials, and pieces you've worked hard to make
- Have the knowledge and tools to troubleshoot your own glazes independently, without having to rely on advice from others that may not apply to your situation
Real results from MGC students...
"Since taking your glaze consistency class in the spring, I have slowly been improving my glazing skills. I just had the best kiln unloading of my life! The main fixes were from witness cones on all the shelves (top and bottom was under firing) and using an electric mixer. I was using a toilet bowl brush and I don’t think it was doing the job. I would never have guessed I was under mixing. Or that my kiln was so uneven. Seems obvious now.
Also, I have an engineering and physics degree, and your explanations of the chemistry and physics of ceramics were the best I’ve ever heard. Everything finally clicked in place."
Lindsey's results before taking MGC on the left and after taking MGC on the right of each photo
Before:
“I reached into a bucket of Selsor Temmoku. The hard panning was immovable, even with quite a bit of flocculating with Epsom salt solution. Are there some glazes that just hard pan after a certain point, and are irreversible, or should I keep trying somehow?”
After:
“I just wanted to thank Sue for her patience in talking me through my burning question about finding that place where SG and viscosity align.
Over the weekend I was able to adjust my formerly hard panning Temmoku to a beautiful non-hard panning glaze and even better yet, discovered the place where my basalt, by alternating additions of bentonite and Epsom salt solution only, made a beautiful (to my eyes) glaze.
I really never could have figured these out without this class. Thank you, Sue!”
"Mastery means no more guessing. Issues can be recognized immediately, and intelligent, science-based steps can be taken to remedy them. I'm more capable, and less a slave to ignorance. 'Knowledge is power,' my dad used to say. I feel powerful, over glaze anyway."
Hi, I'm Sue McLeod
I've been a studio potter since 2010 and spent six years as a ceramics studio technician at a community studio, where I helped potters troubleshoot their glaze problems day in and day out.
That experience taught me something important: glaze issues are almost never random. There's always a reason. And once you understand the reason, you can fix it.
I'm now teaching online full time, and to date more than 540 potters have taken Mastering Glaze Consistency.
I wasn't always the person with the answers though. I remember the frustration of not knowing why things weren't working, and feeling like everyone else had figured something out that I hadn't.
That's exactly why I created this course, and why I teach the way I do. Complex concepts, explained simply. No chemistry degree required.
If you’re ready to take control of your glaze results without sacrificing your body of work to the kiln gods, here’s the path that will get you there:
Curriculum
The course is broken up into 7 MODULES and each module contains several short, easy to digest video lessons.
Module 1 is a preparation module.
The rest of the course is broken into two Phases: The Learning Phase and the Implementation Phase.
Modules 2-4 are the Learning Phase where you’ll learn all the WHATs and WHYs and science behind achieving consistent glaze results. This is where you build your foundation of knowledge.
Modules 5-7 are the Implementation Phase where you’re going to learn HOW to implement your new knowledge through a series of step-by-step tests and experiments to help you fine-tune your glazes and get them working the way you want them to.
Here's an intro video to the course:
Click on each module to read a description.
Module 1 - Setting Yourself Up For Success
Module 1: Setting Yourself Up for Success
The first module will help you get prepared to take this course. You’ll get a detailed description and checklist of all the tools and supplies you’ll need to implement what you learn in the program.
Highlights:
- Start a glaze journal to keep track of your glazing process and connect your process with your results coming out of the kiln.
- Learn all the useful details you can pay attention to while glazing and firing
- Make test tiles and test pots that will give you the most relevant information about your glazes so you don’t have to sacrifice your body of work for the sake of learning.
- Gather the supplies you’ll need for measuring specific gravity, flocculating and deflocculating your glazes.
Module 2 - Why Are Glazes So Inconsistent?
Module 2: Why Are Glazes So Inconsistent?
In this module we’ll go over all the reasons why glaze results are so inconsistent.
Learn the 7 factors that affect glaze results and how to control them – including temperature, cooling cycle, glaze application thickness, bisque porosity, mixing, application method, specific gravity and viscosity.
Highlights:
- Learn about the importance of using Witness Cones for understanding your glaze results.
- Understand the difference between “heat work” and “temperature”
- Understand how the temperature you bisque fire to is affecting your glaze application.
- Learn why insufficient mixing can lead to disappointing glaze results
- Learn ways to improve the consistency of your glaze application whether you’re dipping, brushing or spraying your glazes.
Module 3 - Water Content and Specific Gravity
Module 3: Water Content and Specific Gravity
How does the amount of water in your glaze affect your application and results? How do you know how much water to add to your glazes?
This is where we discuss the concept of specific gravity, why it’s important, how it’s measured and how it’s going to help you control and improve your glaze results.
Highlights:
- Learn how to calculate the amount of water in any glaze, regardless of batch size or whether you mixed it yourself.
- Understand why using a hydrometer is NOT a good way to measure specific gravity and what to do instead.
Module 4 - Viscosity and Flocculation
Module 4: Viscosity and Flocculation
In this module, you’ll learn why water isn’t the only way to change the thickness of a glaze and how the materials our glazes are made of affect glaze application and fired results.
Understand when to use flocculation and deflocculation to adjust your glaze viscosity, instead of only adjusting the water content.
Highlights:
- Learn about the role of clay particles in a glaze recipe and how they play an important part in glaze viscosity.
- Finally understand the concepts of “flocculation” and “deflocculation”, the difference between them, how they affect a glaze on a particle level, and when you should use them to improve your glaze application.
- By the end of this module, your technical ceramics vocabulary will have expanded a great deal. Celebrate by using the word “flocculate” at the dinner table!
- This is also the end of the Learning Phase and you’re now ready to move into the Implementation Phase.
Module 5 - Measuring and Adjusting Specific Gravity
Module 5: Measuring and Adjusting Specific Gravity
Now that you’ve learned all the reasons for measuring specific gravity, let’s go over the steps! We’ll start by going over all the times and situations when I recommend taking a specific gravity reading of your glazes.
You’ll analyze your glazes as they are now and as you’ve been using them. Then you’ll get into adjusting the specific gravity to see how changes in water content affect your fired results.
Highlights:
- Dig out your test tiles and put all your new technical knowledge to practice with some glaze testing.
- Learn my simple, 2-Step Glaze Tuning System that you can use as a guide for all future glaze adjustments
- Learn how to use specific gravity to make sure your glaze results are always consistent and how to adjust specific gravity to suit different glaze application needs.
- I’ll share the trends I’ve seen with specific gravity values for different types of glazes, like matte glazes and clear glazes.
- View my own specific gravity tests with full explanations of my results.
Module 6 - Assessing and Adjusting Viscosity
Module 6: Assessing and Adjusting Viscosity
How do you know when your glaze needs to be flocculated or deflocculated? In this module, you’ll learn a couple of methods for assessing the viscosity of your glaze in order to decide if it needs adjusting.
Highlights:
- Understand when a glaze needs a water adjustment vs a flocculation adjustment
- I’ll share my experiences with different flocculants and deflocculants and explain why I choose the ones I recommend.
- Learn what happens when you add too much flocculant or deflocculant
- Perform my Multi-Viscosity Experiment by testing each of your glazes to find the sweet spot for where they work the best for you.
- View my own Multi-Viscosity Experiments with full explanations of the results.
Module 7 - Improving Glaze Results
Module 7: Improving Your Glaze Results
Now that you’ve learned all the steps for adjusting your glazes and you’ve done some testing of your own, let’s talk about all the ways you can improve our glaze results by implementing what you’ve learned in this course to solve common glaze issues and inconsistencies.
Highlights:
- Gain a full understanding of how to use this course to improve your glaze results and solve common problems that you’re having now or may encounter down the road.
- Learn how to deal with unexpected running, cloudy clear glazes, very thin wares, titanium glazes, cracking/crawling glazes, glaze drying issues and hard-panning.
- Celebrate all you’ve learned by glazing some pots and sharing how your results have improved with others.
Course Schedule
Modules are released on Sundays.
Module 1 is available right away when you register so you can get started gathering supplies and making test tiles.
The course officially starts with the release of Modules 2-4.
All glaze testing assignments are in Modules 5 & 6.
You have lifetime access to all of the Modules.
Zoom Q&A Sessions
The Zoom Q&A sessions will be on Thursdays at 10am Pacific time / 1pm Eastern. They will be recorded and the replay will be added to the course within 24 hours. You'll have the opportunity to pre-submit questions if you can't make it live.
Course Bonuses
Your enrollment also includes:
Bonus: Glaze Resource Library
An extensive collection of articles and videos covering all aspects of glazing and running a ceramics studio. When a question comes up that goes beyond the course content, this is your first place to look.
Bonus: Brongniart's Formula
A short training on how to use specific gravity to calculate the dry weight of your wet glaze. Handy for when you need to add a percentage of a material like a colourant or bentonite to your glaze bucket but don't know the dry weight.
Bonus: Behind-the-Scenes Flocculation/Deflocculation Research Videos
While developing this course I did extensive testing with different flocculants and deflocculants across four different glaze types. I pushed them to their limits so you don't have to. These videos are for the ultra-curious and will solidify your understanding when you're troubleshooting tricky glaze behaviour.
Worksheets, Action Plans, Slides and Transcripts
Every lesson comes with downloadable support materials so you can follow along, take notes and refer back whenever you need to.
What happens when the course ends?
When your four weeks are up, you'll be invited to join The Glaze Lab, my private monthly membership for students who have completed one of my courses. It's not open to the general public.
Inside The Glaze Lab you'll find:
- Two live Zoom calls every month: one with me, and one with me and Ronald Boersen, a glaze chemistry teacher, researcher, and studio potter based in New Zealand, with experience working with ceramic materials from around the world
- An active community where every question gets a thorough, considered answer from Ronald or myself
- Nearly four years of monthly trainings to explore at your own pace, covering glaze chemistry, clay bodies, studio management and more
The Glaze Lab is where you take everything you learned in MGC and keep building on it, with ongoing support and a community of potters who are just as serious about their glazes as you are.
Ready to Get Started?
Enroll in Mastering Glaze Consistency
This is knowledge you'll use for the rest of your pottery career.
Here's everything that's included:
- 7 modules of video lessons with lifetime access
- A step-by-step glaze testing system to find the best application conditions for each of your glazes
- 4 weekly Q&A sessions with Sue on Zoom
- All Zoom recordings added to the course within 24 hours and fully searchable
- A private student community for asking questions throughout the course
- Worksheets, action plans, presentation slides and transcripts for every lesson
- Glaze Resource Library
- Bonus: Brongniart's Formula training
- Bonus: Behind-the-scenes flocculation/deflocculation research videos
Pricing
Pay in Full
$397 USD / $495 CAD
3 monthly payments available at checkout
Pay by PayPal or credit card.
All course videos include closed captions and downloadable transcripts, and can be sped up or slowed down to suit your learning style.
Refund Policy
I want you to be satisfied with the purchase of this program so I offer a money back guarantee. To claim a refund, send an e-mail to support@suemcleodceramics.com by Sat, Jul 25, 2026. This date is after the first Zoom call so you can experience the first four modules of the course and a Q&A session before deciding if the course is right for you. The refund will be processed within 5 business days and may take a little longer to appear on your statement.
MGC Registration is open for:
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Curriculum
View a description of each module of the course
Schedule
View module release and Zoom schedule
Bonuses
See the extra bonuses that are included with the program
FAQs
View frequently asked questions about Mastering Glaze Consistency
Here's what MGC students have to say...
Video Testimonials from past students
(Click to play)
"I've always felt like glazing was my least favourite part of making pottery. I just wanted to get through it ASAP and results were always a surprise. I got tired of spending time making something only to feel overwhelmed by all the stuff I couldn't understand or control during the glazing process. By taking this course, so many of my glazing issues have been addressed. I am looking forward to troubleshooting any problems that come up."
“I will confess I had never measured specific gravity before, so my glaze mixing was really just guess-work. I'm so much more confident now.”
"I've got the know how to make intelligent decisions about my glaze issues or at least, ask intelligent questions."
"I'm a senior and don't have a chemistry background. Sue made it all less intimidating. It's easy to follow, informative and worth every penny."
FAQs
Will this course help me with commercial glazes?
Yes! This course is specifically designed for glazes made from scratch, dry commercial powdered glazes and commercial dipping glazes. I don't personally have experience with commercial brushing glazes but I have had students who only use brushing glazes take the course and say it was immensely helpful.
Do I need a hydrometer to take this class?
No. I'll be teaching you why NOT to use a hydrometer to measure specific gravity and why to weigh your glazes instead. Please DON'T buy a hydrometer to take this class.
Does this course focus on a certain temperature? Cone 04? Cone 6? Cone 10?
No, this course isn't temperature specific. It focuses on helping you achieve consistent glaze application for consistent results at any temperature.
Do I need to mix my own glazes to take this course?
No. Mastering Glaze Consistency is about glaze application, not glaze recipes. You don't need to know what's in your glaze or have mixed it yourself in order to observe how it's applying and make adjustments.
Whether you're dipping, spraying or brushing, you will learn how to be consistent in your process and improve your application technique.
If you only use brushing glazes, there are a few steps that won't be as relevant, but they are still good to learn in case you find yourself using dipping glazes in the future.
I'm not a science person. Will I be able to keep up?
Yes. The only math involved is dividing grams by millilitres. Beyond that, I explain the science through analogies and comparisons that make it easy to understand without needing a chemistry background. You don't even need to remember the science to follow the steps, but it's there for those who like to understand the why.
I've been glazing for years. Will I learn anything new?
Yes, there's a good chance! Many potters go decades without using the processes taught in this course and do just fine.
Some have tried measuring specific gravity or adjusting their glazes and decided it wasn't necessary. But often that's because they didn't learn how to use these tools systematically as part of their process. If you've tried measuring specific gravity with a hydrometer, for example, you haven't learned the method I teach, and that could be exactly why it didn't seem useful.
Regardless of how long you've been glazing, if you're still getting inconsistent results, there's something in this course that can help. Many of my most experienced students tell me they wished they'd learned this years ago.
I'm worried I won't have time to complete the course.
If life is particularly busy right now, that's okay. You have lifetime access to everything in the course, so you can start now and come back to it whenever you're ready. There's no deadline and no pressure.
If you're a working potter who feels like there's never enough time to invest in learning new skills, it's worth thinking about how much time you're currently spending troubleshooting inconsistent results, redoing work, or simply avoiding glazing because you don't feel confident in your process. The time you put into this course now is time you'll save for the rest of your pottery career.
What if I can't access my studio right now?
Even though the course includes assignments to do in your studio, there is also a lot that you can learn just by watching all the course videos. You can do the course now, and then when you get back into your studio you can go back and do all the assignments. You have lifetime access to the course so whenever you're ready to get back into the studio, the course will be there for review.
What does lifetime access mean?
When you purchase this course, you have lifetime access to everything inside your course Hub. This means that as long as Sue McLeod Ceramics is selling this product, you will have access - for the lifetime of the course.
You will receive any updated versions of the product without additional charge.
If the product is ever going to be discontinued (which Sue does not plan or anticipate), she will give you 30 days' notice to download all materials in the program.
Stop sacrificing your body of work to the “kiln gods”.
Stop crossing your fingers and hoping for the best.
Stop worrying about ruining your pieces by glazing them.
Start loving the glazing process because you finally understand how it works.
Your next kiln opening could be the one where everything finally makes sense.
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Questions?
All questions about the course can be sent to support@suemcleodceramics.com. I'd love to hear from you!