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High Bridge Pottery

Member Since 19 Feb 2013
Online Last Active Today, 06:18 PM

#96418 Could Someone Help A Mama?

Posted by High Bridge Pottery on 26 November 2015 - 02:12 PM

If it is the only Dan I know of pottery wise on youtube he has two hands :D although his dad/relation has lost a hand and throws. I bet his wheel is old, it only has three speeds. Not sure of the make.


Try and get some help to move the wheel, I have been moving mine around solo and it gets tough. Easy for two.

#96415 What Is This? Is This Mold?

Posted by High Bridge Pottery on 26 November 2015 - 01:46 PM

I have seen this before on other kins, I think it changes colour because of the different temperatures the bricks see. Never been that dark though.

#96108 What Kind Of Sponge Do You Use When You Are Throwing?

Posted by High Bridge Pottery on 20 November 2015 - 08:52 PM

I like to use a Victorian sponge with jam and butter icing to keep me going while throwing.

#95417 Bubble Bubble Toil And Trouble

Posted by High Bridge Pottery on 07 November 2015 - 06:59 AM

Yes first line is the frit and second is the silica in all three series. Oxidation fired and the tiles are 2-3 inch or about the size of half a credit card.


I had a few rules I wanted to hit when making up these glazes. Have a few different values of alumina so I can see it's effect with viscosity, not contain magnesium oxide or zinc oxide and have no added silica or alumina. I wanted no zinc so it would happily go in reduction and I have been reading about chrome-tin pink needing no magnesium to work well. That's a colour I would like to go for with this glaze.


Glaze A I wanted a good mix of sodium an potassium and they both seem to have the same alumina in each so I added both along with wollastonite and frit till I had a chemisty that looked ok. 

Glaze B was me trying to duplicate the chemistry but get more alumina and silica in from the feldspar so used cornish stone instead.

Glaze C was a slight wild card with really high calcium and frit to keep the silica and alumina real low.


Glaze C on it's own is the most fluid but has visible bubbles where glaze A, less fluid, lost all visible bubbles.


As I was adding silica anyway I thought it was ok to have mismatching silica values. Don't know if it is an epiphanie but interesting that A has more silica and alumina but less bubbles, making me wonder if there is a sweet spot for the silica/alumina melt to saturate with or desaturate quickest.


I notice that too, around the 8-16 silica for A there are many more bubbles but that is where limit formulas tell me the minimum silica should be. Looking at the frit if I also added 16 frit it could counteract the silica. It would also give me a bit too much boron. I think I will have to run some kind of durability test and see how it holds up to acids/bases and such.

I think the crazing is controlled with the lithium and high calcium, be good to do boil,freeze tests too. So many tests....


I agree that glaze B has far more bubbles than A16 silica. I think this is part down to silica but also the alumina. Down at the C tiles adding silica matts out the glaze but doesn't add to many bubbles.

When I was working with the cornwall stone it was obvious it is made up with some clay to achieve the old chemistry. Glaze A was by far the hardest to work with as I had to ram press it into pills, the others I could ball up after 5 seconds on a plaster batt.

Might try this run again but with a few more alumina values and all my feldspars.


Interesting your thoughts about the potash feldspar, I hadn't even noticed glaze A was highest in potassium. Could that be helping the bubbles or is it the Al/Si values. Probably both :D


Be good to try the run again with single feldspars and mixes to see if the cornish stone is causing bubbles or not. I think it probably isn't the material itself but it is in the chemistry that it brings to the glass.


I hope this makes sense as I am not great with explaining myself and writing it down succinctly first go. Really happy with these results, I think with a bit more work on the firing cycle a lot more of these could have been bubble free. Some were so close, I think a longer drop to 1200 would do it or maybe drop to 1220 and an hour hold. I say bubble free, glaze A still has bubbles under the microscope but there is no way you can see them with mk1 eyeball.

#95394 Bubble Bubble Toil And Trouble

Posted by High Bridge Pottery on 06 November 2015 - 06:39 PM

I then added, 2, 4, 8, 16 and 32% extra of silica or frit to each glaze. Increasing silica increases the bubble count which seems to match up with what has been said. Adding the frit increased fluidity and also helped the bubbles escape. I think maybe a slower fall to 1200 or a smaller fall with longer hold could get the last few bubbles out. These were all about 3g balls of glaze. Need to run the tests again but don't want to make all these tiles again  -_- 
First shot is a little out of focus, my bad.

#95361 Bubble Bubble Toil And Trouble

Posted by High Bridge Pottery on 06 November 2015 - 05:29 AM

Thank you for sharing your research Tim :D Seems like you are in the same area as me, started with the obvious removing LOI and trying a few different firing curves with no avail. Interesting that the same is happening be it low fire or high fire. I will be interested to know what happens using a finer mesh silica.
Here are a few more of my tests. I made up these glazes to try and have a few different alumina values with similar(ish) flux and not have any added silica or kaolin.
Glaze A is actually bubble free to the eye, you can't see any, glaze B has many bubbles and glaze C has the odd one or two. C is the most runny with A pretty close and B far away from the two but it does have much more alumina and silica.
I fired 150c/hour to 1140 then 60c/hour to 1260 with 15 hold. From there I did a fall, 60c/hour to 1200 with a 30 min hold.

#95261 The Great Pottery Throw Down

Posted by High Bridge Pottery on 04 November 2015 - 08:01 AM

Watched the first episode this morning, had some weird sexual tone throughout. Maybe just me who doesn't get it.

#95260 Nilserik Stool From Ikea

Posted by High Bridge Pottery on 04 November 2015 - 07:45 AM

I thought neilestrick had a stool named after him in IKEA  :unsure:

#95128 Community Challenge #4

Posted by High Bridge Pottery on 02 November 2015 - 10:08 AM



Welcome to the community challenge #4

This is a place where we can challenge ourselves alongside other community members to create ceramic works within the constraints set out in each challenge.
The Challenge
This challenge is to make a hydria.
The Rules

  • Everybody can enter the challenge, all you need is a registered account on the forum.
  • Work in progress (WIP) images are encouraged. It can help to talk through your research and ideas but please don't spam the topic. Keep the updates informative and succinct.
  • One final entry per community member, images no larger than 1024 pixels wide/high.
  • Attach images to your final entry post along with the text Final Entry - Forum Name
  • This will make sure you are not missed out of the results thread. Also make sure you post your final entry in this thread to be entered into the challenge.
  • The challenge will run quarterly and will be
    • 1st February to 29th April, 
    • 1st May to 30st July, 
    • 1st August to 30st October, 
    • 1st November to 30st January.
  • The results thread will be posted on the last day of the ending month. It will be a collection of all the entries into one post for condensed viewing and some post challenge discussion.

The Rest
Remember you are entering for your own enjoyment and there could be a risk that your work develops into something new and exciting.
Be considerate of others and don't post opinions without good reasons to back them up. We are all here to improve and progress with our ceramics.
Some dates may vary slightly as this is a community run project and it will depend on members having access to the forum.
Have any ideas for a challenge? Post them in the ideas thread http://community.cer...hallenge-ideas/

#95071 Community Challenge #3 - Results

Posted by High Bridge Pottery on 01 November 2015 - 09:08 AM



















#95070 Community Challenge #3 - Results

Posted by High Bridge Pottery on 01 November 2015 - 09:07 AM

This challenge was to make "anything but round". Here are the results  :D


Diesel Clay





High Bridge Pottery










Evelyne Schoenmann











#94927 Qotw: Are You Living Your Dream, Or Dreaming Your Life?

Posted by High Bridge Pottery on 28 October 2015 - 04:58 PM

My dream is to exist and my existence is a dream. It's a strange paradox that I won't understand till I am dead.

#94666 Community Challenge #3

Posted by High Bridge Pottery on 22 October 2015 - 06:42 PM

Final Entry - High Bridge Pottery


These are a continuous idea I have been working with since college. Love them every time I make them and they are anything but round. These are the reason for my gas kiln conversion :D



#94659 Crank Clay Body Formula

Posted by High Bridge Pottery on 22 October 2015 - 04:25 PM

You seem to have missed the formula Neil gave and dwelling too much on it being called 'crank'


A stoneware clay plus grog IS 'crank clay'

#94597 Glaze Test City

Posted by High Bridge Pottery on 21 October 2015 - 08:13 AM

I am sure you were not making light of it :D There is no black or white with how you use the brain. Just a pet hate of mine how OCD gets used to explain cleaning the house or enjoying things in their 'right' place.


I have always loved chemistry but never knew their was so much in ceramics when I started. Ceramics is a great area of study as you say, many different skills and techniques required so lots to keep you stimulated and explore.


I am yet to find anywhere near as much beauty in the arts as I find in science but ceramics is a good mix of creating and creation(science/universe) Glaze testing makes me feel like the earth. Reading up on geology and how magma/lava crystallise into rocks and then making these rocks my own lava flows on rocky pots!  :D Love it