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Rebekah Krieger

Uneven Glaze..

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I did my first non commercial glaze ... I plugged in a public recipe to Glaze mixer.  I am having difficulty with the glaze going on evenly. When I dip it, it's too thick. But when I brush it its all strange and gathers where it wants to and doesn't apply evenly. I have always used brush on commercial glaze before this.  The inside of the bowl is obviously not even, and the outside doesn't appear to have much glaze at all.  Not sure how to overcome this. 

 

 

 

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Here is another non commercial glaze I had mixed at Glaze mixer. This one is a Matte.  It shows how uneven it is because the clay body is dark.  I have watched videos on applying glaze but they all seem to dip and have a beautiful Medium layer. 

post-19612-0-38310000-1381237723_thumb.jpg

post-19612-0-38310000-1381237723_thumb.jpg

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ok and this is the most embarrassing... uugh this one has brush marks, I vertical and horizontal.  This is after I dipped the glaze and it was soo thick that i worried about my kiln wearing a thick layer when it was finished so I washed it off and re applied with the brush.   --- I think this wins the award for the ugliest shino glazed Item I have ever seen! 

post-19612-0-62443800-1381238288_thumb.jpg

post-19612-0-62443800-1381238288_thumb.jpg

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Marcia Selsor    1,301

Are you wetting the pot a little before you dip?

This will cut the absorption down. Or you could thin the glaze a little to avoid the excessive thickness. Are you using a hydrometer. I never have. I use the knuckle test. Put a dry finger into the glaze and pull it out. If the lines in your knuckle are showing, it is good. If not, too thick.

Marcia

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neilestrick    1,381

I have never wet my pots before dipping. It limits how much glaze the pot can accept. Glazes that are mixed for dipping will not brush well at all. Additives are necessary to make them brushable. Every glaze goes on differently. Some show drips more than others. I mix my glazes to a thick chocolate milk consistency and dip for a 6 count.

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Marcia Selsor    1,301

I either do a fast rinse in a bucket, or use damp sponge. I always clean my pots before glazing. They are usually ready to go by the time I get the glazes stirred up.My glazes are mixed for dipping according to my practice of dampening the pots. If I don't dampen the pots, the glaze goes on too thick.

Neil's advice is also true for the way the glaze is mixed for application. We have all developed our personal methods.I dip and count to 10....but my pots are slower to absorb the glaze because of previous dampness...not wet and not soaked.

 

Marcia

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bciskepottery    925

On your mug, think about using a liner glaze on the inside and the matte glaze on the outside.  A matte finish is often obtained when the glaze materials are not fully melted and you get a neat crystal that makes the surface matte.  But that could lead to some issues with leeching on surfaces that are in contact with food or beverages.  Is the matte glaze copper based?  Nice handle. 

 

On your wine cooler, a truly bad shino is a carbon-trap shino that comes out snot green.  Did you allow the pot time (a few hours or overnight, preferably) to dry after you washed the first glaze off and before applying the second coat?  If you did not allow time for the wash water to evaporate, the difficulty in glazing may have been because the pot was too water logged from the washing and the bisque could not absorb the water out of the second coat.  Basically, you just moved the second glaze coat around resulting in uneven application and brush marks.

 

Like with most things pottery related, you get better with practice.  Don't worry; make another pot. 

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This is where I got the Matte Recipe  http://cone6pots.ning.com/profiles/blogs/vals-turquoise    Except my recipe does not have epsom salts as an additive.  That glaze turned out more true to color on another pot I made.. same issues with uneven glaze, that chocolate clay body is tricky to match up.   I think I will consider a liner glaze.  I never washed off glaze before - so I didn't know to allow it more time to dry. I was anxious to load the kiln and just needed that last item.. and here I pay the price! HA

 

 

Absolutely - I need the practice!! 

 

Thanks about the handle compliment. It's nice to know something is sort of working ;)  

post-19612-0-38424900-1381325737_thumb.jpg

post-19612-0-38424900-1381325737_thumb.jpg

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By the way- if any of you see a common flaw I am doing in my pots, I would love the feedback. I have been doing this (on my own between advice here and youtube) since May of '12 so I am sure I am making lots of rookie mistakes. I need more hands on help with experienced potters, youtube is not quite the apprenticeship one needs LOL!! 

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Marcia Selsor    1,301

Matt glazes that are intended to be matt glazes mature at the firing temperature and can run even it they are matt. It is dependent on the Alumina :Silica ratio in the base.

 

The uneven application is the problem. Brushing on a matt glaze isn't working for you. The application is thin in spots. You need more glaze on the piece.

 

Marcia

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You are trying new glaze applications/new glazes, so you are a beginner in that regard. You are experiencing what I used to tell (before I retired) my beginning pottery students, a "What you do is what you get" result. Then I'd explain why certain glazing problems occur and how to prevent them. You have been given some good advice here already. You are trying to get more even coverage.

 

Here's my addition:

 

I wax first so wax dries faster (on a dry pot). I then always very quickly rinse my pots and very quickly dry off with a clean, dry towel, to both remove dust and prevent the glazes from going on too thick (especially if overlapping/double dipping). I then wait a few minutes before glazing... (Other potters do it differently yet we are all making pots, so, whatever you like's okay as long as it's working.)

 

Brushing? Are you using a good, "fully charged" (full of glaze) "Mop" style brush? Google it to see. Use a mop brush and apply with pot either on a real good, heavy, long-spinning banding wheel, or place and center the pot on your potters wheel and turn slowly. Fewer brush strokes will show. I have applied glazes this way before (without adding fillers, since I like glazes to be a brush-able and dip/pourable), to fine result.

 

Better still, dip or pour or both.

 

Mix enough glaze to pour the inside. Fill to about half way, pour back out while turning pot to coat inside. Allow to dry. (Practice application on bisque ware/any suitable container half filled with water until you get the technique down.) Have enough glaze so you can dip the outside, holding the inside with both hands with fingers pointed outward if possible, keeping pot right-side up and horizontal. I dip in and out. I do not "count." That's because I have mixed my glazed to a thickness I desire, no "counting" is needed. Keeping the pot level, I dip in and out at a reasonable speed but not so fast as to splash or so slow as to saturate the pot with water.

 

Allow to dry. Touch-up the rim by scraping off (use a blade of some kind) uneven areas and painting/banding on - with a "fully-charged" brush (meaning one that holds enough glaze to make it around the rim) (use poters-wheel or banding wheel) about 3 med-thin coats to equal same thickness as poured/dipped glaze on pot.

 

If you don't have enough glaze to dip the outside, after glazing the inside as described above, place pot - upside-down - on a couple of dowels/small sticks over a container, and pour glaze over quickly, starting on one side. Best if you make it all the way around before the glaze "start" side dries.

 

Allow to dry. Clean foot completely (so you won't have to handle it much after finishing lip/rim), and scrap uneven areas off this blade where pot and dowels/sticks met to create even appearance. Or, use a scraper/blade to remove all glaze from rim/lip and apply fresh, even rim glaze with brush on banding wheel/potters-wheel.

 

These techniques make it easy to apply different glazes on inside than outside. 

 

I suggest always finishing all glaze coats on the inside before glazing the outside, unless you are using dipping tongs. (Glossy glazes are desirable for the inside of functional ware.)

 

Dipping tongs are another story... "In and out and upside down" quickly enough that glaze is still flowing as the pot is removed thus evening out... Have sponge ready to dab glaze off bottom. Keep upside down until it dries enough to not drip when you turn it right-side up. I won't get into tongs any further for now. Decent tong glazing (sans "snake-bite" tong marks, etc.,) is a whole, long explanation.

 

Advice on your pots? When looking at people's pottery, look as closely at the foot and bottom as you do the rest of the pot. How did the potter complete the bottom? The shape and size of the foot in regards to the overall pot? Are there feet you like? Try them out on your pots. Footless? Fine, just remember the bottom of your pots is where one's name usually is, so be tidy. Good pottery designers have a 360 degree involvement with their pottery.

 

Also, Make lots of pots. The more clay that passes through your hands, the better you'll get. 

 

Best of luck!

 

Lena

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You are trying new glaze applications/new glazes, so you are a beginner in that regard. You are experiencing what I used to tell (before I retired) my beginning pottery students, a "What you do is what you get" result. Then I'd explain why certain glazing problems occur and how to prevent them. You have been given some good advice here already. You are trying to get more even coverage.

 

Here's my addition:

 

I wax first so wax dries faster (on a dry pot). I then always very quickly rinse my pots and very quickly dry off with a clean, dry towel, to both remove dust and prevent the glazes from going on too thick (especially if overlapping/double dipping). I then wait a few minutes before glazing... (Other potters do it differently yet we are all making pots, so, whatever you like's okay as long as it's working.)

 

Brushing? Are you using a good, "fully charged" (full of glaze) "Mop" style brush? Google it to see. Use a mop brush and apply with pot either on a real good, heavy, long-spinning banding wheel, or place and center the pot on your potters wheel and turn slowly. Fewer brush strokes will show. I have applied glazes this way before (without adding fillers, since I like glazes to be a brush-able and dip/pourable), to fine result.

 

Better still, dip or pour or both.

 

Mix enough glaze to pour the inside. Fill to about half way, pour back out while turning pot to coat inside. Allow to dry. (Practice application on bisque ware/any suitable container half filled with water until you get the technique down.) Have enough glaze so you can dip the outside, holding the inside with both hands with fingers pointed outward if possible, keeping pot right-side up and horizontal. I dip in and out. I do not "count." That's because I have mixed my glazed to a thickness I desire, no "counting" is needed. Keeping the pot level, I dip in and out at a reasonable speed but not so fast as to splash or so slow as to saturate the pot with water.

 

Allow to dry. Touch-up the rim by scraping off (use a blade of some kind) uneven areas and painting/banding on - with a "fully-charged" brush (meaning one that holds enough glaze to make it around the rim) (use poters-wheel or banding wheel) about 3 med-thin coats to equal same thickness as poured/dipped glaze on pot.

 

If you don't have enough glaze to dip the outside, after glazing the inside as described above, place pot - upside-down - on a couple of dowels/small sticks over a container, and pour glaze over quickly, starting on one side. Best if you make it all the way around before the glaze "start" side dries.

 

Allow to dry. Clean foot completely (so you won't have to handle it much after finishing lip/rim), and scrap uneven areas off this blade where pot and dowels/sticks met to create even appearance. Or, use a scraper/blade to remove all glaze from rim/lip and apply fresh, even rim glaze with brush on banding wheel/potters-wheel.

 

These techniques make it easy to apply different glazes on inside than outside. 

 

I suggest always finishing all glaze coats on the inside before glazing the outside, unless you are using dipping tongs. (Glossy glazes are desirable for the inside of functional ware.)

 

Dipping tongs are another story... "In and out and upside down" quickly enough that glaze is still flowing as the pot is removed thus evening out... Have sponge ready to dab glaze off bottom. Keep upside down until it dries enough to not drip when you turn it right-side up. I won't get into tongs any further for now. Decent tong glazing (sans "snake-bite" tong marks, etc.,) is a whole, long explanation.

 

Advice on your pots? When looking at people's pottery, look as closely at the foot and bottom as you do the rest of the pot. How did the potter complete the bottom? The shape and size of the foot in regards to the overall pot? Are there feet you like? Try them out on your pots. Footless? Fine, just remember the bottom of your pots is where one's name usually is, so be tidy. Good pottery designers have a 360 degree involvement with their pottery.

 

Also, Make lots of pots. The more clay that passes through your hands, the better you'll get. 

 

Best of luck!

 

Lena

Thanks!  I wish there was a photo to go along with your descriptions. But I think I understand.  As for the foot, yes, I struggle a lot with them, they are rough and groggy.  They annoy me the most out of my pots. I purchased 2 bowls at a local pottery that had beautiful bottoms.  After that I got depressed. LOL!  I have tried to ask here how to make the bottoms smoother, I have so far experimented with the rubber rib to see if that helps... it only does slightly. Thank you for the advice!! 

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More suggestions (trimming this time) following your comment to my posting to you above:

 

After trimming a groggy clay body pot, you can take a damp sponge and as pot spins med. speed, apply sponge to trimmed parts of pot to raise a bit of slip. Don't over do it or you'll just wash away fine clay and leave a groggier pot than you started.

 

You can often dampen fingers and treat foot like you would a rim-compression, depending on wetness level. sometimes that is enough.

 

Or you can take the burnishing end of the modeling stick (the curved rounded end of stick some use to trim away support clay ay bottom, etc.), and while the wheel still turns, burnish in the grog. This "packs it back" into the surface.

 

Don't leave the part of the pot you intend to glaze "burnished" though (the glaze could be more likely to crawl there). Go over that part again, as wheel spins, to quickly raise a slip surface that will now resemble the untrimmed surface, thus the glaze will behave closer to the same way on all surfaces. Finish with a final burnishing with the modeling stick, and you may use finger "foot compression" move again too, to make a nice smooth foot that will not be as likely to scratch furniture. 

 

Have fun learning! 

 

Lena

 

P.S. Here are some trimming demo photos (start there and click forward). https://www.facebook.com/photo.php?fbid=10201698754417846&set=a.10201698722737054.1073741831.1449636499&type=3&theater

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Biglou13    202

More info on shino it looks yummy on inside of pot.

Pottery forms look good hard to tell without holding.

I'm not a big fan of that wide foot on small pot first picture........ Unless your developing that "style" for more of your works.....

Matte lookedd good if u didn't tell me it was a flaw I wouldn't have known.

Most of your glazes look thin in application.(but you've already heard that). If worried about kiln make catch trays or trivets for pieces to sit on. Then glaze heavy......

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Lena and Biglou

 thank you for the insight and tips. That little pot was supposed to get a handle and become a small mug but I let it dry too much so it has an  odd shape. ;) I Purposely leave a wider foot on some bowls fr avoiding tipping/ top heaviness such as in a yarn bowl or utensil holder.  I like the look of my smaller trimmed feet.  I have here 2 pictures... one of recent bowls  that I trimmed, and one pic of 2 beautiful bowls that I did not make. I am green with envy when I see the underneath of a bowl look this perfect.  

post-19612-0-73953300-1381381209_thumb.jpg

post-19612-0-10314500-1381381258_thumb.jpg

post-19612-0-73953300-1381381209_thumb.jpg

post-19612-0-10314500-1381381258_thumb.jpg

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Mark C.    1,798

Good feet are something to work towards. I spent the better part of a year working with a Mentee on her feet.She had been throwing 10 years.

You can have a great looking form but if the foots not good ita all for not.

You already have a great tool and thats looking at others feet.

Find your own style and refine that foot.

Mark

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Min    778

I have found that with grogged clay that the feet will always be a little rougher when taken from the glaze firing than non grogged bodies. I think this is because grog is made from prefired ground clay and so has already shrunk somewhat. When the clay is fired the grog shrinks less than the rest of the clay and therefore protrudes very slightly where there is no glaze to smooth over it. (like on bottoms and feet)  A flexible diamond sanding pad will make the clay as smooth as non grogged (like in the pot in your last photo). For flat bottomed pieces a lapidary diamond disc attached to your wheel with a pancake of clay makes glass smooth bottoms. These run about $40, the flexible pads around $15

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For those who do not put it on their wheel, what kind of sander do you use? can you take a pic? My husband works in a machine shop and he has a few choices. Once we figure it out, I will just be going there with each batch to get them done. 

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Mart    23

Here is another non commercial glaze I had mixed at Glaze mixer. This one is a Matte.  It shows how uneven it is because the clay body is dark.  I have watched videos on applying glaze but they all seem to dip and have a beautiful Medium layer. 

 

????

This look really nice as it is.

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