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High Bridge Pottery

Member Since 19 Feb 2013
Offline Last Active Yesterday, 08:10 PM

Posts I've Made

In Topic: Newbie - Why Wouldn't A Glaze Dry On Bisque?

21 October 2016 - 02:40 PM

Did you mix your glaze with porcelain slip before using it as a glaze? Lots of clay in a glaze makes it dry slowly.

In Topic: Homemade Gas Updraft Kiln, Not Enough Temperature Any Help :)

21 October 2016 - 02:38 PM

BTU per cubic foot.


9" hard brick

Cone 10 - 10,000 to 16,000

Cone 6 - 8,000 to 13,000


The 9" means a 9" thick wall if I remember correctly so if we can hopefully estimate double that for the 4.5" then you only need 25-30,000 btu. The problem is you can put that much gas into the kiln but you can't burn it to get heat out of it. Not enough space or air. Two smaller forced air burners could do it. I have always wanted to try a kiln this small and thought Bunsen burners that you use in science labs could be a good start.

In Topic: Stumped By Ftl Code

19 October 2016 - 02:33 PM

So it spits this code out when it is 4 hours over the segment time? I had a relay that would overheat and stop working because it had fancy safety features. Could be that along with some lost insulation in the repair job getting your electrics extra hot. Only some thoughts.

In Topic: Glaze For Satin/matte Dinnerware Safe Porcelain Black Clay

19 October 2016 - 02:09 PM

I am not even sure that black pot has been glazed. Any glaze I have seen that's close is 40-50% clay and on the border between glaze and slip. It is always going to be abrasive on cutlery and probably unhygienic because that's part of the lovely surface.


Blacks generally mean there is a higher percentage of colouring oxides so more to leach out into your food. How much actually makes it into your body I don't know, never seen any experiments. If you are not using any toxic metals then it can be classed as food safe in that area even if the surface is not exactly hygienic.

In Topic: Epic Fail Making Slabs

18 October 2016 - 01:22 PM

There is a lot to be said for how you recycle the clay. I think most of the shortness is to do with not getting the water in between every clay particle. Excess water over bone dry clay (a good 3 inch of water above the clay line) and multiple mixing over a week or so then another few weeks to let the water evaporate so it was an acceptable consistency to dry out on a plaster batt. It takes time and space, not something everybody can do. I guess I am ageing in excess water instead of mixing and then ageing at the right consistency.


I also try and add all the throwing slop back in to keep as many of the tiny particles or anything else in the water.


I don't like rolling slabs and will get to the right thickness by cheesewiring with a harp or thickness guides and then rolling if I have to. Even if your surface is plaster and not making the clay stick it always sticks to my rolling pin. Finally I can't even roll something the same thickness and get a more even slab with a wire.