Understanding Pottery Chapter 19 Glaze Defects

Поделиться
HTML-код
  • Опубликовано: 4 ноя 2024

Комментарии • 81

  • @mjcomiskey8340
    @mjcomiskey8340 3 года назад +16

    This is by far the best tutorial I have ever seen on glaze defects. My thanks! I am very sorry to learn that Mr. Berneburg has passed away. What a great loss for the pottery community. I am hoping that someone in his circle could help me. I am wondering a substitution of Frit 3134 for Gerstley Borate is a 1:1 substitution. Thanks in advance.

    • @WashingtonStreetStudios
      @WashingtonStreetStudios  3 года назад

      MJ Comiskey, Thank you for the question. I will do my best to respond the way Phil responded to me. Frit 3134 is not a 1:1 substitution for Gerstley Borate, at least not in all cases. It depends on what the glaze needed from the gerstley borate. There is lots of data if you search this on the internet, and you will find some say it works and others say it doesn't.
      Phil always told me to create a small test batch of the glaze, then create line blends to figure out how to get the results you are looking for. You may not be able to create the same glaze, and you may find a new recipe that you like.
      These videos may help: Making Test Blends for Glazes and Clay Bodies (ruclips.net/video/zantVEjfLmY/видео.html), An Introduction to Glaze Testing Part 1 (ruclips.net/video/bZRJAVwifwA/видео.html) and Part 2 (ruclips.net/video/PqQl8mN6nI0/видео.html).
      Best of luck and I hope this helps.
      Please share the channel with your freinds and fellow potters to help us grow our community.

  • @octaviaengres
    @octaviaengres 10 месяцев назад

    I really love his sense of humor and teaching skills. God bless you, Mr. Phil.

  • @fntkm97
    @fntkm97 5 месяцев назад +1

    Thank you so much Mr. Berneberg!

  • @ACUPOINTKAT
    @ACUPOINTKAT 3 года назад +1

    I am still in deep dark forest but I lern a lot here. Thank you. Sending love, Kat.

    • @WashingtonStreetStudios
      @WashingtonStreetStudios  3 года назад

      Thank you Kat, enjoy the rest of the videos and tread lightly in the deep dark forest!

  • @kadensmike8190
    @kadensmike8190 3 года назад +5

    A treasure box of useful advice! Thanks.

    • @WashingtonStreetStudios
      @WashingtonStreetStudios  3 года назад +1

      Thanks Kaden, let us know if there is a topic you would like explored and be sure to share the channel with your friends and fellow potters!

  • @christinecook5547
    @christinecook5547 Год назад +1

    such a thorough, brilliant tutorial. Thank you so much!

  • @wendythompson2629
    @wendythompson2629 4 года назад +4

    Thanks very much Phil for sharing all of your years of knowledge. You explain things so clearly.

    • @WashingtonStreetStudios
      @WashingtonStreetStudios  4 года назад

      We hope you enjoy the videos and find them helpful! Please share with your friends and fellow potters!

  • @ryangreene3288
    @ryangreene3288 2 года назад +1

    Fantastic content. First time watching. You’ve got yourself an avid fan instantly.

    • @WashingtonStreetStudios
      @WashingtonStreetStudios  2 года назад

      Awesome, there are lots of videos, I hope you enjoy them all! And share the channel with your friends and fellow potters to help us grow our online community.
      Thanks for watching.

  • @pollyannwhite5343
    @pollyannwhite5343 3 года назад +1

    Thank you so much. You answered at least three of my queries regarding glaze problems. Hope all is well over there. Very best wishes from the East Riding of Yorkshire, England.

    • @WashingtonStreetStudios
      @WashingtonStreetStudios  3 года назад

      Polly Ann, Life is good here, we are getting vaccinated and hopefully can start returning to 'the new normal' soon! Thanks for the encouragement and for keeping us on the international scene!

  • @raineboots
    @raineboots 3 года назад +1

    I watched this after picking up my failed glaze fired pieces. Thank you so much for sharing this information. I’ve learned so much!

  • @creepycuteceramic
    @creepycuteceramic 2 года назад

    I don't understand why there are not so many likes but many views. Mr Phill deserves all the love♥️

    • @WashingtonStreetStudios
      @WashingtonStreetStudios  2 года назад +2

      Thank you Петр Полежайкин, Mr Phil Berneburg passed away in July and left this video series as his legacy. He was very pleased that thousands have seen his videos when he passed. Keep watching and share with your friends and fellow potters, help us grow his legacy!

  • @AmyPalatnick
    @AmyPalatnick 5 месяцев назад +1

    this is brilliant. thank you!!!

  • @plantspresents7111
    @plantspresents7111 2 года назад +1

    Best resource I found 🙌🏻 thank you! 🙏🏻

    • @WashingtonStreetStudios
      @WashingtonStreetStudios  2 года назад

      We are so fortunate to have completed these videos before Phil passed away! Thanks for the encouragement!

  • @eucalyptustrees
    @eucalyptustrees 3 года назад +1

    This series is really helpful. Thank you to all involved in making these videos!

    • @WashingtonStreetStudios
      @WashingtonStreetStudios  3 года назад

      Thank you for your encouragement, I hope you enjoy all the videos! Please share the channel with your friends and fellow potters to help grow our community!

  • @miniarora1477
    @miniarora1477 Год назад +1

    Very new to ceramics and finding this so useful. Sad to know Mr Berneburg is no longer with you us. If anyone can help me understand why one of my items with clear glaze crazed and yet others in the same firing with same clay didn’t. It was a large flat piece so bit different in shape.

    • @WashingtonStreetStudios
      @WashingtonStreetStudios  11 месяцев назад +1

      There are so many possible variables. The most likely is dust on the surface. Could also be placement in the kiln, or uneven glaze application. I tend to spray larger pieces to get the glaze applied evenly.

  • @michellestarnes4228
    @michellestarnes4228 3 года назад +1

    Thank you for taking time to explain everything! I'm a newbie that kinda just jumped in lol. I'm loving your videos!

  • @cindyrodger4867
    @cindyrodger4867 3 года назад +1

    Excellent talk! Thanks

  • @TheMarnaiz
    @TheMarnaiz 3 года назад +1

    Fantastic video. Thank you so much.

    • @WashingtonStreetStudios
      @WashingtonStreetStudios  3 года назад

      Thanks MaZ, Phil does a great job explaining glazes, resolving problems and he develops some good recipes at the studio too! Thanks for watching and being part of our community!

  • @JulianaSilvaCamargo
    @JulianaSilvaCamargo 2 года назад +1

    This video is so good, i na from brazil and it helps me a lot, thank you

    • @WashingtonStreetStudios
      @WashingtonStreetStudios  2 года назад

      Juliana Camargo, Great! Please share the channel with your friends and fellow potters to help us grow our online ceramics community. Thanks for watching and for the encouragement.

  • @stuhaysman135
    @stuhaysman135 3 года назад +1

    Brilliant and hugely helpful - having just tested a new clear glaze recipe and ended up with a milky bubbly mess!

    • @WashingtonStreetStudios
      @WashingtonStreetStudios  3 года назад +1

      Stu, It's great that you found the video useful! Anyone who has searched for a clear glaze recipe has probably experienced a milky mess or bubbly mess or both! Please share the channel with your friends and fellow potters to help us grow the community!

  • @sachinpnsachu1587
    @sachinpnsachu1587 3 года назад +1

    Thank you sir. Thank you so much.

  • @weedayna
    @weedayna 3 года назад +1

    I am a polymer clay artist who is considering switching to ceramic. The amount of challenges with ceramics is so daunting. I make detailed sculptures and I cannot imagine even one of them getting ruined beyond repair. I would be so heartbroken. It makes me not want to bother with ceramics at all. Thanks for the informative video. I got a lot to consider

    • @WashingtonStreetStudios
      @WashingtonStreetStudios  3 года назад +1

      Although a lecture like this makes it seem as though there are only pitfalls, there are a multitude of successes! the defect lectures are presented to help you deal or avoid issues in ceramics. If you have local ceramic artists you can work with you will be able to achieve great results! The results make the journey worthwhile!

    • @weedayna
      @weedayna 3 года назад +1

      @@WashingtonStreetStudios I appreciate the advice. My sister is a successful ceramic artist and she recently had defects in about $3,000 worth of merchandise. Unfortunately she hasnt been able to figure out what went wrong. Thats the part that freaks me out so much. The fact that the pitfalls are out of your hands sometimes and you dont necessarily know how to fix it.

    • @WashingtonStreetStudios
      @WashingtonStreetStudios  3 года назад +1

      I totally understand. We would be happy to see if we can provide some clarity. Can you send more information to washingtonstreetstudiosinc@gmail.com and we'll take a look? please send the following:
      Clay Body (manufacturer and identifier, or recipe if it's a custom clay)
      Glaze (manufacturer and identifier, or recipe if it's a custom glaze)
      Pictures of the defects or issues
      Without knowing this information, it's hard to diagnose the issues. And if she uses her own custom recipes, rest assured we will not share or use the glaze recipe without expressed written consent.

  • @sofiabernardo7966
    @sofiabernardo7966 Год назад +1

    very useful video so well explain! the best to be aware of every thing so defects can be reduce but i wish there was another with how to fix the defects after they ocurred😂. like if there was a overfired is it possible to refire and remend the default?

    • @WashingtonStreetStudios
      @WashingtonStreetStudios  Год назад

      Possible? Maybe, I’m not sure I would trust that it’s food safe, or safe from shards. It’s not worth the risk in my opinion.

  • @piipottery8837
    @piipottery8837 3 года назад +1

    Excellent video!!! Phil, What possible solutions do you find for delayed crazing? I work with earthenware clay

    • @WashingtonStreetStudios
      @WashingtonStreetStudios  3 года назад

      Pii Pottery, I have forwarded your question to Phil and I will post his response when I receive it!

  • @deepashtray5605
    @deepashtray5605 3 года назад +1

    In my limited experience crazing is a great deal more prevalent in clear glazes. I'm hypothesizing that this is due to the glaze shrinking as its ingredients are cooked off. In my last firing one glaze did fine totally opaque at cone 6, but as the temp increased (I have a very hot bottom shelf) to the point where it becomes clear glossy glaze it crazes... a lot. Did this on 2 separate glaze recipes in this same firing.

  • @ionelima9637
    @ionelima9637 2 года назад +1

    thanks you

  • @lorrainecliftonceramics
    @lorrainecliftonceramics 3 года назад +1

    Hi a really interesting and helpful talk. I’m getting pinholes, only on flat platters. Very slow bisque to 1060 degrees C and glaze firing to 1220 degrees C (04 and 6). Same glaze on verticals pots is not pinholing. Any advice, gratefully received or solutions to some beautiful platters. Thank you

    • @WashingtonStreetStudios
      @WashingtonStreetStudios  3 года назад

      Lorraine, I've forwarded your question to Phil and I will post his response when I receive it.

    • @WashingtonStreetStudios
      @WashingtonStreetStudios  3 года назад +1

      Hi Lorraine,
      My guess would be that the platters are not getting hot enough, long enough in either firing because they are lying flat on the kiln shelves, especially if they do not have “feet” or foot-rings. Because of their thickness and mass, and their orientation with respect to the electric kiln elements, most kiln shelves heat up slower than the pots sitting on them. You could test this by raising the platters up off the shelves using short kiln posts, such as one inch, or other supports. Also, try firing to a lower cone and adding a “hold” at the end to achieve the same final cone rating (for example, fire to cone 5 and then add a 20 to 25 minute hold). Check using cones.
      Good luck,
      Phil

    • @lorrainecliftonceramics
      @lorrainecliftonceramics 3 года назад

      @@WashingtonStreetStudios Hi Phil - thank you so much for your help - I will try and see what happens. Will let you know .....

  • @caitlinrathburn7133
    @caitlinrathburn7133 3 года назад +1

    I love all your videos! Thanks for helping me understand more of the science around ceramics! I was wondering if I could ask your advice. I have an old kiln with a simple kiln computer that can do two ramps, a hold and a controlled cool. I bisque to cone 03 and glaze fire to cone 7. My thermacouple isn't completely accurate but I use cones so I know despite the temperature reading I get, that my programs successfully fire to these cones. 100C per hour until to 1085 C and then 25 per hour to 1185, 20 min hold, and then cooling 100 C/hr to 1085 C. I'm getting A LOT on the inside bottom of my bowls and I think it's pinholes that I am getting on the outside (I can see down to the clay and the edges are soft). Do you have any recommendations on how I can change my program to avoid this? The clay's top range is 1280 C and the glaze is for 1260 C according to labeling. Do you have any suggestions as to how I can get rid of bubbles on pieces if I fire them a second time? I've tried simply refing. That didn't work. I recently tried scraping the tops of the bubbles off with a broken pieces of kiln furniture, rinsing and then applying glaze over those spots and refiring. The bubble was gone! but I need to test that more... Thanks!

    • @WashingtonStreetStudios
      @WashingtonStreetStudios  3 года назад +1

      Caitlin, Thank you for your encouragement and question. I've forwarded the question to Phil and I will post his response when I receive it. Keep watching!

    • @WashingtonStreetStudios
      @WashingtonStreetStudios  3 года назад +1

      Caitlin, can you send pics to washingtonstreetstudiosinc@gmail.com for Phil to look at?

    • @WashingtonStreetStudios
      @WashingtonStreetStudios  3 года назад

      Hi Caitlin,
      Thanks for your email! Without actually seeing the piece, it’s difficult to come up with a specific explanation. The fact that refiring didn’t help, yet adding glaze and refiring did is a little confusing. I don’t believe that the bubbles could be actual pinholes because of your relatively high bisque firing temperature and your slow firing schedule, unless your clay is particularly “dirty” with a lot of impurities, such as a very dark stoneware. My guess would be that the bubbles are either the result of underfiring (especially if the bottoms of the bowls are thick), or less likely, overfiring (however, your firing temperature seems to be well within the quoted range for the glazes), but placement within a kiln can have a large effect on temperature.
      Phil

    • @caitlinrathburn7133
      @caitlinrathburn7133 3 года назад

      @@WashingtonStreetStudios Hi! Sorry! I did't see your response! Thank you! I guess I don't get notifications from RUclips. I have some pictures for you now and some more info! I'll email you if that is still okay! Tacks! Caitlin

  • @kaylagil1441
    @kaylagil1441 3 года назад +1

    i made about 4 plates and 2 of them completely cracked in half! They were perfectly fine after the bisque firing but when it came to the glaze firing, they didn’t make it. This happened two times and I am wondering why it is only happening to two or three of them? I am using cone 5/6 stoneware clay and glaze

    • @WashingtonStreetStudios
      @WashingtonStreetStudios  3 года назад

      Kayla, the likely culprits are a lack of compression to the main structure of the plate and the rims of the plates drying before the base. To help control the drying, check out this video: ruclips.net/video/wER6OozWjhQ/видео.html
      For more details on what is happening check out this video: ruclips.net/video/Fviy1p9dNqs/видео.html
      If you are hand-building the pots, compress the clay in three or more different directions with a rib, turn the slab over, and compress again in three or more different directions before you make the final plate form.
      If you are throwing the plates on the wheel, compress the plate multiple times with a sturdy rib to align the clay platelets into the same orientation.
      Then control the drying by covering the plates with plastic overnight, uncover for a few hours, then cover again, repeat to allow the plates and rims to dry evenly without causing undue stress to the main structure of the plate.
      I hope this helps, let us know if it works! Also, send pictures if you have more failures to washingtonstreetstudiosinc@gmail.com.

  • @JohnSmith-fw2et
    @JohnSmith-fw2et 3 года назад +1

    If I use a commercially prepared glaze and it crazes, how do I fix the crazing problem to make the glaze food safe

    • @WashingtonStreetStudios
      @WashingtonStreetStudios  3 года назад

      John, great question but without a good answer! The problem in addressing crazing in a commercial glazes is that without the actual recipe it is difficult to know what is causing the crazing. Can you let us know which commercial glaze you are using? It is a longshot, but we may have some experience with the glaze.

  • @tszkwan1996
    @tszkwan1996 4 года назад +1

    Hi sir, is that crazing happended when clay and glaze went to fire and underwent in ununiform expansion and contraction rate? Was that the fired bisque clay got glazed, then went to the second firing and have different expansion rate?

    • @WashingtonStreetStudios
      @WashingtonStreetStudios  4 года назад

      Rita, Thank you for the question. I sent it to Phil and he will respond soon.

    • @WashingtonStreetStudios
      @WashingtonStreetStudios  4 года назад +1

      Hi Rita,
      Thank you for your email. Crazing happens at the end of a firing as the fired clay and solidified glaze are cooling down because the clay and the glaze are contracting different amounts. If the glaze tries to contract more than the clay, then it will crack and break apart into small areas - this is the crazing. As you are probably aware, most materials expand as they are heated and then contract as they cool back down, but different materials (different chemical compositions and crystalline forms) expand and contract at different rates (the CTE - coefficients of thermal expansion). So, if the glaze has a higher CTE (more expansion and contraction) than the clay, it is likely that crazing will occur.
      Phil

  • @ClownWhisper
    @ClownWhisper 3 года назад

    I know a lot of people including myself that are firing primarily a cone 6 and our plagued with pinholes I can't figure it out I'm actually spending $1,000 on Monday to buy a wall mounted skutt kiln controller. I have tried different bisque temperatures and I can't get rid of these pin holes and they're showing up in most of my glazes where the same buckets of glaze didn't do this before I changed out elements. To most people this would indicate perhaps too high of a temperature but my witness cones claim that it's right on the money. I am very perplexed I have been working with John Britt to try and solve this

    • @WashingtonStreetStudios
      @WashingtonStreetStudios  3 года назад

      Unfortunately Phil passed away in July and he could have helped solve the problem. He did help me solve the problem when I had pinholes on many of my pots. Since the pinholes were surfacing on multiple glazes, we focused our attention on the clay itself. I raised the bisque temperature under the assumption the organics in the clay were not burning out during the bisque and were surfacing during the glaze firing. I ended up bisque firing to ^05-04 for that batch of clay. I have since gone back to ^06 for bisque since I no longer experience the issue.
      Do you use plaster in your studio? If you do, plaster dust settling on the clay or glaze can cause pinholes or craters if they absorb water from humidity and don't release it until higher temperatures.
      If John Britt can't solve it, I surely won't be much help! Good luck solving this one!
      At least you're getting a kiln controller out of this ordeal, do you fire manually now?

    • @rheahalona
      @rheahalona 3 года назад +1

      @@WashingtonStreetStudios I’m so very sorry to hear of his passing. I just found this video this morning and it has been hugely helpful in assisting me in figuring out a blistering problem. I’m going to try to refire and see what happens. Is it possible to email you all with additional questions? I don’t know if there are additional people on your team who can provide technical assistance.

    • @WashingtonStreetStudios
      @WashingtonStreetStudios  3 года назад +1

      @@rheahalona you can certainly email me, I knew Phil for 15 years and learned a bit!

    • @rheahalona
      @rheahalona 3 года назад

      @@WashingtonStreetStudios will do! Thank you!

  • @shukrieh
    @shukrieh 2 года назад +1

    Can grazed ceramic dishes be repaired?

    • @WashingtonStreetStudios
      @WashingtonStreetStudios  2 года назад

      Do you mean crazed?
      If you have crazing on a pot, where the glaze has separated and left areas without glaze, you can try to apply more glaze and refire the pot. Spray the crazed area with hairspray to help the glaze stay in place, since the pot is no longer pourus. I've tried this several times with limited success. These days I just send the pot to the shard pile or use it for decoration in the garden!
      Good luck.

  • @ahmedbilal6148
    @ahmedbilal6148 4 года назад +2

    ❤️❤️❤️❤️❤️❤️

    • @WashingtonStreetStudios
      @WashingtonStreetStudios  4 года назад

      We are pleased that you enjoyed the video, there are many more. If you haven't subscribed, please do, you will be notified when new videos are posted.

  • @1christian1sonne1
    @1christian1sonne1 Год назад

    🙂