PeterH

A search for "pizza stone" or something similar will throw up a lot of hits.
As you will want to include archived threads in your search, best to use a  browser search something like
site:community.ceramicartsdaily.org baking stone
... which found the following threads, with a fairly common theme - buy a kiln shelf, if only because you cannot get a suitable clay.
Starting with an eerily similar question to your own.
 
 

 

A search for "pizza stone" or something similar will throw up a lot of hits.
As you will want to include archived threads in your search, best to use a  browser search something like
site:community.ceramicartsdaily.org baking stone
... which found the following threads, with a fairly common theme - buy a kiln shelf, if only because you cannot get a suitable clay.
Starting with an eerily similar question to your own.
 
 

 

May I suggest that you make a few more birds, a little practice/experimentation goes a long way.
Then maybe try for a hollow bird
How to make a hollow bird form using thumb pots
... Make a small through hole with a skewer to let any steam generated during firing escape.
You can make some bowl-ish items by draping thin class clay slabs over a balloon.
e.g. clay over a balloon https://www.pinterest.co.uk/jazzdd76/clay-over-a-balloon/
... which also mentions a few projects, such as

More balloon ideas at Pottery Ballon Technique https://www.pinterest.ca/black3200/pottery-ballon-technique/

Article on Turner's white with some examples
It Slices, It Dices! Some Simple Glaze Tests Reveal a Ceramic Glaze That Can Do it All (well, almost)
https://ceramicartsnetwork.org/daily/article/It-Slices-It-Dices-Some-Simple-Glaze-Tests-Reveal-a-Ceramic-Glaze-That-Can-Do-it-All-well-almost
.. I notice it says under Colour Development
The second part of our project was to use Turner's White as a base, but just exclude the Zircopax (an opacifier).

I agree with Pres: the biggest thing you can do to reclaim clay in a timely manner is to have a smaller reclaim bucket that obliges you to do it more often.
Also, if space is a problem, you can build stacking frames to do reclaim on, similar to the principle Tom describes. This article (there’s a paywall, but you can access 3 free articles a month) describes how to build a gravity filter press. All you need are some 2x4’s, hardware cloth/chicken wire and a thrift store bedsheet. You can use this method to build stacking frames that have a smaller footprint, and even have separate trays for the different clay types.
I do my reclaim on a similar setup, and I find as long as your slurry isn’t super fluid, you don’t need the plastic to catch the runoff. I aim for a pudding consistency. 

Article on Turner's white with some examples
It Slices, It Dices! Some Simple Glaze Tests Reveal a Ceramic Glaze That Can Do it All (well, almost)
https://ceramicartsnetwork.org/daily/article/It-Slices-It-Dices-Some-Simple-Glaze-Tests-Reveal-a-Ceramic-Glaze-That-Can-Do-it-All-well-almost
.. I notice it says under Colour Development
The second part of our project was to use Turner's White as a base, but just exclude the Zircopax (an opacifier).

May I suggest that you make a few more birds, a little practice/experimentation goes a long way.
Then maybe try for a hollow bird
How to make a hollow bird form using thumb pots
... Make a small through hole with a skewer to let any steam generated during firing escape.
You can make some bowl-ish items by draping thin class clay slabs over a balloon.
e.g. clay over a balloon https://www.pinterest.co.uk/jazzdd76/clay-over-a-balloon/
... which also mentions a few projects, such as

More balloon ideas at Pottery Ballon Technique https://www.pinterest.ca/black3200/pottery-ballon-technique/

Hi Maria and welcome to the forum!
Is this the Turner's White recipe you used? If it is did you include the zirconium opacifier both in the past and with this current batch?

Re wax resist, the type you use overtop of another glaze makes a big difference in how it behaves.
Both oil based and water based wax resist will work but the water based one is much more time and moisture sensitive than the oil based one. If you use a water based wax resist overtop of glaze it can curl up and loosen it's hold on the base glaze. The longer you leave it before glazing over the worse it is.
With wax based resist this issue is avoided.
Some resist labels don't tell you if they are oil based or not though, you can tell by how the resist washes out of brushes. If the brushes stay a bit gummy when washed with hot water then it's oil based. If the brushes easily wash clean then it's water based.

Depending on how one's wax resist behaves, try brushing on wax resist after the stenciled material has dried some, afore pulling the tape, voilà!
...in the case one doesn't want the next layer to cover the pattern.

I also found this forum  because general searches found some very interesting postings on it.
When I want to use a general browser (mine is google) I default to using site:community.ceramicartsdaily.org
PS Just for interest I tried three google searches
"red clay" and community.ceramicartsdaily
"red clay" community.ceramicartsdaily
"red clay" site:community.ceramicartsdaily.org
Which returned 12,700, 15,000 & 594 results respectively. (The order, and possibly the number,  of results may/will-be influenced by my previous search history.)
Repeating the searches a few minutes later I got 13,400, 15,400 &  757 results.
Just reporting the number of results, not judging their quality.

Sometimes I combine mold parts to test out new design ideas.  Sometimes the mold parts do not fit well together. I find filling the small holes/gaps with slip, FROM THE OUTSIDE, to be  a simple remedy. Let the slip set up for a few minutes and you have a "sealed" mold.  THEN fill the mold cavity with slip.
You can also fill the gaps from the inside but I find it hard to get my hands inside smaller molds.
 
 

I agree with you on the jabs and removed them as this place is not for that -sorry as I degressed .I thank you for that reminder as well. Its all about clay nothing else .
Now on point Laguna has a 3 year supply at current consumption rates of Gretsly Borate. The mine is played out and this supply is all that will be ever.
In terms of The EPK shortage-yes it real and Laguna says it a weather supply mine/ chain issue. Its also happening to red clay and other materials this year due to  wacky weather issues they said. Storms and rain he said are so bad its really affected many products they use (we use in clay). One can assume as weather is a changing in many spots  on the planet this will only get worse.
The best policy is to stock up when you can.
 

I also found this forum  because general searches found some very interesting postings on it.
When I want to use a general browser (mine is google) I default to using site:community.ceramicartsdaily.org
PS Just for interest I tried three google searches
"red clay" and community.ceramicartsdaily
"red clay" community.ceramicartsdaily
"red clay" site:community.ceramicartsdaily.org
Which returned 12,700, 15,000 & 594 results respectively. (The order, and possibly the number,  of results may/will-be influenced by my previous search history.)
Repeating the searches a few minutes later I got 13,400, 15,400 &  757 results.
Just reporting the number of results, not judging their quality.

I also found this forum  because general searches found some very interesting postings on it.
When I want to use a general browser (mine is google) I default to using site:community.ceramicartsdaily.org
PS Just for interest I tried three google searches
"red clay" and community.ceramicartsdaily
"red clay" community.ceramicartsdaily
"red clay" site:community.ceramicartsdaily.org
Which returned 12,700, 15,000 & 594 results respectively. (The order, and possibly the number,  of results may/will-be influenced by my previous search history.)
Repeating the searches a few minutes later I got 13,400, 15,400 &  757 results.
Just reporting the number of results, not judging their quality.

I also found this forum  because general searches found some very interesting postings on it.
When I want to use a general browser (mine is google) I default to using site:community.ceramicartsdaily.org
PS Just for interest I tried three google searches
"red clay" and community.ceramicartsdaily
"red clay" community.ceramicartsdaily
"red clay" site:community.ceramicartsdaily.org
Which returned 12,700, 15,000 & 594 results respectively. (The order, and possibly the number,  of results may/will-be influenced by my previous search history.)
Repeating the searches a few minutes later I got 13,400, 15,400 &  757 results.
Just reporting the number of results, not judging their quality.

Tony Hansen strikes again.
in https://digitalfire.com/picture/2463
The incredible utility of 3D printing master handle molds
As a parting-agent I use Murphy's Oil Soap on the 3D-printed PLA mold, this makes it fairly easy to extract the freshly-cast plaster molds (the sidewalls have a draft of about 5 degrees).

I was reminded of a different approach to the same 3D printing idea. It used sacrificial 3D prints, and produced moulds with minimal  excess plaster.

3D Printing a Mold for a Slipcasting Mold
https://www.instructables.com/3D-Printing-a-Mold-for-a-Mold/

Obviously horses for courses, but maybe something for your notebook.

For non-brits, the UK 13A ring main is described in
http://wiki.diyfaq.org.uk/index.php/Ring_circuit
The ring circuit and BS 1363 plug and socket system were developed in Britiain during 1942-1947.(ref 1) They are commonly used in the United Kingdom, and to a lesser extent in the Republic of Ireland.
The ring circuit came about because Britain had to embark on a massive rebuilding programme following World War II.(ref 2). There was an acute shortage of copper, and it was necessary to come up with a scheme that used less copper than would normally be the case. The scheme was specified to use socket outlets with 13 Amp fused plugs.
...
The ring circuit was devised during a time of copper shortage to allow two 3kW heaters to be used in any two locations and to allow some power to small appliances, and to keep total copper use low.

I still am Interested in the whole kiln measurement it could give us an idea what condition ALL the connections are in. Having said that, it appears the kiln at 2.5 kw has trouble making cone 6.  So, measure both elements, then measure where the power comes in at - for total kiln resistance (No Power applied)  to assess just how good all those connections are. My sense is the connections may be removing some available power but in the end the elements were changed to get this to go to cone 6 and even at their current worn state wattage, they are not really able to power effectively anymore.
Which leaves you with what wattage works? Sometimes it’s easy to look at similar models and note what wattages are offered to achieve a temperature / cone. My sense is this thing was upgraded to 3000w and now has dropped to 2500 w. due to wear and tear and has trouble making cone 6.
I would rule out the bad connections first though, just in case we find out they were decreasing the potential power by a few hundred watts. Finally to know the actual firing wattage measure the amperage if possible, and yes knowing this we can derive the heated resistance.

I've  been thinking along similar lines, but wondering if they are 220v elements run at 240v.
As power is proportional to V^2, this would give (240/220)^2*2000  ~2380w at 240v.
... probably not good for element life, so your series comment seems even more appropriate.
PS
220v would give 2000w with a resistance of 220^2/2000 = 24.6 ohms. So if the current resistance is 26 ohms that's about 100*(26/24.6-1) ~ 5.6% gain over time.

You can run up to 3kw through a 13 amp fuse no problem. 
 
Those elements are wired in parallel so you need to use 1/RTotal = 1/R1 + 1/R2 
If I assume the bottom element has the same ohms as the top 52 ohms you measured it comes out to 26 ohms (2.2kw) for RTotal so it seems like they may have upgraded the elements to draw 2.5kw.
 
You will be better off switching from parallel to series elements as then they can use thicker wire and the elements should last longer. I do agree if you order a 2kw set they will probably be worse than what you have now.

The diagram below may help. Your 2 kw kiln ought to measure: 240^2/2000w = 28.8 ohms.  So we dont know if these are series (additive) or parallels which would generally half the measurement but what we can say is if the resistance measured at the cord end (where it plugs into the wall) should be about 28.8 ohms to produce 2000 watts of load. Higher measurement, means wear and less heating watts. So measured in total or at the cord end that plugs into the wall or where power is applied. if you are approx. 10% or more above 28.8 ohms (28.8 + 2.88  = 31.68) then they are worn. Just make sure all measurements are done safely, (no power) and both elements do glow when they are powered. Sounds likely they are worn.
You may find formula circle below handy

A couple of minor points if you are still trying to increase the crazing.

1) Always ink-up (part of) your test-tiles. It can sometimes be hard to see the true extent of the crazing. It also gives you a better idea of the number of cracks which occur after the initial inking.
an example from Digitalfire
 
2) I understand that glaze programs are not too accurate at estimating the absolute COE of a glaze, but  they are quite good at estimating the change to the COE that small change to the recipe/chemistry will make. So maybe you are reaching the point where they might be useful.

See Using Calculation to Fit a Glaze in https://digitalfire.com/article/understanding+thermal+expansion+in+ceramic+glazes

It might be interesting to try a crazing test on your test-tiles, such as

IWCT - 300F:Ice Water Crazing Test
https://digitalfire.com/test/iwct

If only to judge the effect of any changes you make to the recipe/firing.