PeterH

To leak slowly. A quick test is to fill the teapot and leave it on a paper towel overnight. The towel should remain dry.

@oldlady In case it's of any use I've reformulated your problem as an exercise in form-filling. I hope that it breaks things down so that each step seems like a logical progression. The idea is to look at what you have done so far and calculate a NewRecipe which is a scaled copy of the original recipe which is: - large enough to accept all the ingredients already in your bucket - and at least the size of the original recipe ... and then calculate the AdditionsNeeded to the bucket to match the NewRecipe. As you didn't list your full recipe I've tried to reconstruct it (as a 10,000 gram batch with a 2% addition of bentonite). So check I've got things right. Here is the form. which is filled in column by column. Note that BatchSize is the largest number in the MinBatchSize column (or 1, whichever is greater). PS This seems to give the same results that Min has already posted.

Just for the record a cone 6 controlled cooling cycle for glaze development is given in https://ceramicartsnetwork.org/daily/article/Super-Cool-Slow-Cooling-in-an-Electric-Kiln Natural cooling down to 1900 F(the poster seemed to get 500F/hr but programmed 9999F/hr) 125-175F/hr down to 1450F (tweak based on glaze results) Natural cooling down to room temperature

You will need to PM them, they last visited here on Jan 10.

I wonder if a more water resistant/repellent material would help. (Like both of Min's suggestions.) Materials used in stenciling might also work, and translucency/transparency could help when cutting out the patterns. But that would probably mean art-shop prices. https://ceramicartsnetwork.org/pottery-making-illustrated/pottery-making-illustrated-article/Stenciling-on-Clay# Stenciling on Clay PS A recent article on stencils which are very finely cut. Shows just how far people can push things. https://ceramicartsnetwork.org/daily/article/how-to-use-vinyl-stencils-and-underglaze-for-beautiful-surfaces How to Use Vinyl Stencils and Underglaze for Beautiful Surfaces

Idle thoughts. This may be the best way of avoiding the maths! (Besides asking your very willing friends to help.) The problem seems to be restarting the mixing after an interruption (a phone call in this case). Maybe after an interruption it's worth taking the time to: - Write the recipe down on a scrap sheet of paper - Tick off the ingredients you have already added - Add the extra ingredients, ticking as you go.

@Kelly in AK +1 Maybe even start experimenting with a DIY pizza stone. PS If you use baking paper it makes it easier to move the risen bread mix onto the baking surface and reduces any potential problems with surface porosity/sticking. Probably reduces the thermal shock just a little as well.

Pre-heating from cold seems to be recommended practice. Don't know how severe the thermal shock is when you place the bread into the cloche. https://delbuonosbakery.com/mastering-bread-baking-with-a-cloche-a-comprehensive-guide/ Cloche Preparation: Begin by placing your bread baking cloche, both the base and the lid, in a cold oven. It’s essential to allow the cloche to heat gradually with the oven to prevent thermal shock, which can damage the stoneware or earthenware. ... obviously only put the hot cloche down on an insulating surface, such as wood. Interesting to see how nicely rounded the the transition from base to wall is. Probably because the resultant alignment of the clay particles minimizes the chances of type H cracks when it's thermally shocked. https://ceramicsfieldguide.org/pdf/materials-handouts/ClayCracks.pdf PS The subject of pizza stones comes up from time to time. Kiln shelves are often recommended - as a body less subject to thermal shock. So should you ever need a flat baking stone ...

A google search for site:community.ceramicartsdaily.org ovenware identifies several threads you may find interesting. A lot seems to depends on how carefully the pot is going to be used. ... added because it emphasizes the edge between wall and floor

A couple of threads that discuss deflocculating slip to get both the moisture content and the "thickness" right for the task in hand. PS Thanks to Min for the reminder in a different thread.

Interesting, I tried reloading and it still works for me. http://masteringglazes.com/mastering-cone-6-glazes/frequently-asked-questions.html PS Happy to send you the pdf if you pm me your email address.

I just used my very old analogue ammeter to read the mains voltage in my UK house. I got 245V +/- 5%. My equally old digital meter (accuracy unknown) oscillated between readings of 239V & 240V. @davelea As Neil said measure your voltage. If your house is really receiving 240ish volts then I think there may be valid concerns running a kiln with elements designed for a 230v supply. But the experts are much better judges of that than I am. BTW if your supply is 240V changing the elements to ones designed for 240V looks like a complete fix. The question then is does this need to be ASAP, or can you just wait until the elements need changing? I'm leaving that to the experts. The fact that you will be running hotter once the controller lets you may be significant. PS For the record I think that the "nominally 230v" was a good idea technically. It helped create a unified market for (most) electrical goods in Europe (not just mainland Europe). The downside was that it introduced a certain amount of bureaucratic double-speak, whose impact seems to have worsened over the years. At the stroke of a pen the nominal 220v European supply became nominally 230v, and the UK nominally 240v supply became nominally 230v. While as intended the actual voltages supplied didn't change at all. (Although there could have been longer term changes in these voltages as the electricity grids changed over time). Looking at wiki https://en.wikipedia.org/wiki/Mains_electricity_by_country France and Germany are listed at an unqualified 230V, although the legislation said 230V -10% +6% (i.e. 207.0 V-243.8 V). The UK is also listed as 230V, although a footnote leads to an article that states that the range is really 230V +10% - 6% (i.e. 216-253v or 234.5V +/- 18.5V).

A couple more references on slow-cooling (which only has an effect if there is crystal growth during cooling). https://ceramicartsnetwork.org/daily/article/Super-Cool-Slow-Cooling-in-an-Electric-Kiln https://cone6pots.ning.com/forum/topics/slow-cooling

You might find this page of interest. http://masteringglazes.com/mastering-cone-6-glazes/frequently-asked-questions.html It examines the effect of cooling one of the mastering cone 6 glazes at different speeds. http://masteringglazes.com/_Media/slowcoolingseries_med.jpeg

Well not quite -- as the UK supply is nominally 240V not 230V. Since WW2 most of continental Europe has used a 220V supply, while the UK used 240V. Come European “harmonised voltage limits” they showed "neither fear nor favour of the two sides" and defined things in terms of 230V. https://leadsdirect.co.uk/knowledge-base/what-is-the-difference-between-uk-voltage-and-european-voltage/ So: - The UK's nominal 240V became the range 230V -6% +10% (i.e. 216.2 V – 253.0 V) - Europe's nominal 220V became the range 230V -10% +6% (i.e. 207.0 V-243.8 V) - This effectively means there is no real change of supply voltage, only a change in the “label”, with no incentive for electricity supply companies to actually change the supply voltage. So the UK supply voltage remains nominally 240V. ... and the same kiln draws about 4.3% more current and about 8.9% more power than it would from a nominally 230V supply. PS Equipment designed to operate correctly of a voltage range 230V +/- 10% can operate on either of there standards, and most goods on the market are moving towards this. BUT this isn't possible for simple heating devices. - Europeans don't want their fan heaters to run 9% cooler than UK ones! - A 9% hotter incandescent bulb runs brighter, but has a significantly short lifespan. (I found out the hard way). - Kilns!