Bill Kielb

It’s a wheel, at 2.2 amps you are free to use most any three wire extension cord. So 3 wire 16/3, maybe 15 ft is rated well beyond your wheel. I would change the receptacle it is plugged into to a gfi receptacle  with appropriate cover from weather. You can buy a cord with the gfi built in, but they are fairly pricey.  I would not use this outdoors unless protected by a GFI though. A GFI can only protect you if the cord has all three prongs and the wheel has a three prong plug.

I think all thats been mentioned above are great. I would add from an expectation standpoint If you are constructing a fuel fired kiln especially for a first time, there will likely be a decent learning and testing curve. Great fun and usually very educational for those that persevere and succeed.

Don’t fire on drywall it will smolder and burn once calcined. Used to be type X 5/8” - approx. 60 minutes, 120 minutes to sustain a flame. I like the shelf idea and unless once firing, you can grog / silica the shelf after bisque. Many of our large format sculptors would build on a very straight shelf on top of a four wheeled cart.

I do not have a preferred store purchased overglaze. I spent a whole summer trying to resolve this for our cone 6 glazes so our artists could paint freely with most underglazes. The solution was to modify a clear with a bit more boron to more completely melt. If this is your issue then testing other commercial. over glazes  as well as lighter coats of underglaze  are probably your best bet.
I have never noticed a difference between clays but only anecdotally tested on the variety of studio clays used at the time. Color, thickness applied and even underglaze supplier had the greatest effect - all reasonably resolved with a slightly lower melting temperature of the modified clear. Not all under glazes will go to cone 10 as well with significant color change often being the effect of higher temperature. All our artists, especially sculpture test their underglazed for color. It was not uncommon for a sculpture artist to say, I need to stop at cone 2 - no higher as the perfect color of a full sized human bust that took them a month to make might change from what they wanted. A bit tedious, but an example of all tested in advance.

Pictures for sure for ideas. One experience  - Not all clear glazes melt well over underglazes so the underglazed decorated area can be locally refractory. The end result for this defect, bumps, orange peel, glaze that does not cover and melt well to a smooth finish. Often mistaken as over fired and bubbling. Additionally if heavily underglazed, when applying glaze over the top the underglazed area is far less absorbent than naked bisque so it can be hard to apply glaze over the top evenly. Spray applying overglaze and drying is one way to get a pretty even coat over the entire ware.
Pictures for sure here as there can be other reasons for sure. Most underglazes need to be tested with their overglazes in the manner they will be used to be reasonably sure the combination works as intended.

Hard to know the formulas for sure of commercial glazes but there are many sources for glaze recipes. Glazy.org is one web resource. Making glazes for many potters is a thing though, often to save on the high cost of commercial glazes but also often to design glazes that are very durable, to their coloring and finish preferences. You can browse glazy (and others) for something that might be similar.

Pack the middle the tightest.
Have you tried just using the cone 08 preprogrammed firing schedule?

Is there any US charity you can turn to for advice. (In the UK Citizens Advice might be worth trying.)

Copper is interesting and there are limits but most often found in an industrial setting when testing for heavy metals.. Sounds like you need a real environmental air test and lab analysis to figure this out ……… then figure out the source. Clay may or may not be a concern here so a real test with real quantities of constituents likely is the best way to know with reasonable certainty. For now, no exposure or very limited exposure until you can correct seems important. Adding cleaning chemicals, moisture etc… can amplify effects. I suggest get  a real test and lab analysis ……. on paper by an industrial hygienist or equivalent.

Copper is interesting and there are limits but most often found in an industrial setting when testing for heavy metals.. Sounds like you need a real environmental air test and lab analysis to figure this out ……… then figure out the source. Clay may or may not be a concern here so a real test with real quantities of constituents likely is the best way to know with reasonable certainty. For now, no exposure or very limited exposure until you can correct seems important. Adding cleaning chemicals, moisture etc… can amplify effects. I suggest get  a real test and lab analysis ……. on paper by an industrial hygienist or equivalent.

Didn't see anything in the news a few weeks ago; I'd missed this, "The EPA says the smells near the Reilly Tar & Chemical Co. Superfund site matched benzene, pyridines and ammonia." from Neighbors concerned over years of bad smell prompts action from EPA (wrtv.com)
The article includes a photo of Tibbs Ave/Minnesota St intersection, which is... 105 miles away, perhaps not related.
Best wishes for identifying the problem(s) asap.

Copper is interesting and there are limits but most often found in an industrial setting when testing for heavy metals.. Sounds like you need a real environmental air test and lab analysis to figure this out ……… then figure out the source. Clay may or may not be a concern here so a real test with real quantities of constituents likely is the best way to know with reasonable certainty. For now, no exposure or very limited exposure until you can correct seems important. Adding cleaning chemicals, moisture etc… can amplify effects. I suggest get  a real test and lab analysis ……. on paper by an industrial hygienist or equivalent.

I'm seeing Evenheat model 1210 described thus (where the volts, amps, and watts values line up):
"The RM II 1210 is the ultimate personal ceramic studio design. The RM II 1210 is designed to fire china paints and clay materials up to 1800°F (982°C), cone 07 on a daily basis."
Note, the 2280 value stamped on the depicted plate is labelled "watts"...
...looks like the low fire model there SierraRed18!
The 1210B  Evenheat model, however, is 240v, 3120 watts, rated cone 10, 2350°F ("High Fire")
 

The Sentry FTH error is similar to the Bartlett E1, in that both are in response to the controller detecting the temperature not rising as expected according to the program. The difference is that the Sentry continues to fire, albeit slowly, until the target temperature is finally reached, whereas the Bartlett error will terminate the firing.

If it's the manual Bill mentions an "F-1" message doesn't seem to conform to the format of the other alarm messages (none of which have a hyphen). Can you confirm exactly what you see?
PS
BTW it looks to me like a message containing "F 1"  would be generated while setting the safety temperature.

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Hi and welcome to the forum.
From Standard's website and their  Lowfire Slip page there is a link with glaze recommendations. Duncan IN1001 "slightly yellow, may blur crisp underglaze lines". There are four other Mayco glaze result descriptions there also. It seems the least yellowing recommendation is Spectrum 700. Standard recommends doing both bisque and glaze to cone 04.
Link here: https://cdn.shopify.com/s/files/1/0039/8177/0841/files/105-LFW_Glaze_Rec.pdf?v=1674848426

Many years ago I made a birdbath.  The pedestal is a shaped open cylinder with the bowl sitting on top.  I soon discovered that the local raccoons liked  to get up to the water and tipped the bowl over and cracked or broke it a couple of times.  The last bowl I made had a deep - 5 - 6 inch foot on it to fit inside the cylinder so the raccoons couldn't tip it off the top anymore.  Lin

A few years ago and older gentleman (bowling buddy) asked me to make him one to fit on his base as he had left the old bowl out in the winter. I have a plaster form that fits on the wheel that is a low dome about 20" across. I used a SC 630 at the time, and it did take me a few days to figure out how to make it right. I ended up throwing the bottom on the dome using a 2 inch thick slab that I pulled out to about 1/2 "  with a foot ring pulled that was wide enough to fit over the base with allowance for shrinkage. I then made walls on a separate bat that were thrown cylinder raised 2 " and same thickness as the base. I attached the two pieces when leather hard and waited until bone dry before bisque firing. The first one I fired on the foot ring. . . .It cracked. The second I fired upside down no problem, and then fired the glaze on the base with glaze sponge cleared foot ring.  He is still using this today as I have talked to him often, and he is very happy with the result.
 
best,
Pres

One thing that comes to my mind for large pieces,  is it will shrink and grab on the shelf. The rim and likely the grid if flush at the bottom will tend to drag on the kiln shelf. The grid itself if not reasonably even could also cause this to warp and bend depending on variance in thickness and construction.  A waster slab and thin even silica beneath and between comes to mind to keep it smoothly moving and from grabbing. Same for glaze firing, although predicting distortion I think is tough without having tested a few shapes and if glazing only one side could deform the shape. Sounds like you can glaze both to a large extent. Quartz inversion (IMO)  is almost not a thing as every piece in every firing goes through it twice each firing the world around (probably millions of pieces). Having said that a reasonable slow speed helps with the rate it shrinks and there is no reason to go to cone 04 so neither of those suggestions sounds silly. We do multiple bisques with layer applications of underglaze but always bisque to lesser temps just to set each layer of underglaze.  There is no reason to waster the energy or stress the piece.

Hi Alex,
Welcome to the Forum!
Good questions.
Moisture:
Water is driven off (as vapor/steam) during the firing process, true, however, the majority of the wet clay's water is lost via evaporation whilst waiting on the kiln.
In addition to drying raw ware in the Studio, add evaporation from clay trimmings; open throwing, cleanup, mopping buckets; just glazed wares; damp - just cleaned - surfaces; any other open containers of wet stuff.
Fumes:
Several gasses (besides water vapor) are produced when clays and glazes are fired.
Kiln fumes (digitalfire.com)
The typical powered kiln vent (that pulls a stream of superheated kiln atmosphere from a small hole in the bottom of the kiln and expels it outside via a duct) gets most, but not all the fumes. With provision for adequate make-up air*, a kiln vent may be adequate.
Better, imo, would be to open up doors and windows whilst firing and run a powered kiln vent.
Even better, a powered kiln vent and an overhead hood with a powerful fan**.
Dust:
Working with clay, some dust will be generated, however, dust can be minimized via consistent housekeeping and "low dust" practices.
Number one culprit, typically, is dry clay on the floor.
Next might be the wedging station.
A wet mop for floors and a bucket and sponge for work surfaces can make a big difference.
There are several archived threads on fumes and dust here!
*air coming in to replace what is being pushed out by the fan.
**an overhead system can help with accumulated heat - firing a kiln indoors will heat the space, a lot!

FTL message usually indicates not enough power to get to temp. Worn element(s), bad relay - some mechanical or electrical reason it cannot maintain a reasonable rate of heating at the end. On the test tile side, Orton says most of the important (flux) heat work work will be done in the last 200-250f degrees given a reasonable rate of rise during this period. If your kiln stops well short of that last 200-250 degrees then generally things can be restarted as if nothing significant happened. 
In your case, you are sort of close so restarting likely fine if you can make temp at a reasonable rate. If it stalls again though you are going to need to diagnose the problem and those tiles are likely half baked and depending on the stall temp can end up looking any number of ways. If you have witness cones in place then plus one - you will have an idea of how much heatwork you achieved. If virtually none, then repair the kiln and refine.
My guess is it stalled for a reason and It will stall again. My rule of thumb is if it stops 250f or more before it’s final temp it usually can be cooled and refired after repairs with it likely ending up looking / firing as normal. In effect no heatwork was done during the most important phase.

While Fast glazing may / may not be a problem, fast bisque generally not the greatest practice unless you know your clay has burned everything out in that timeframe. To slow things down modify your turn up schedule leave it on low for longer or turn it up less. Duncan provides calibration instructions for the switch. It may be too old to calibrate but following the analysis part should reveal if it is just too worn and needs to be replaced.
For now, just as a test, I would slow down the bisque simply by firing slower, more in the 8-12 hour range for sure to see the effect on your clay and glaze. If you leave it at the 10:00 position and do not turn it up, how long to 04? If that extends the firing, then calibrated or not calibrated you have an option to slow things down to test with.

Yes it will
Yes  I do, but it is complex so testing may have helped here. My guess is it would help. Total guess though.
 
Pres used grog, I think I said silica, alumina is great too. Pres had the super excellent idea of applying thin and  evenly with a salt shaker though. All can work, all require care not to spread around the kiln. Grog is probably neatest, then silica, then alumina.

Just perhaps an easy thing to remember - Flat plates with a hole in them start off with a pretty distinctive stress concentration. Have seen many a clock face crack just like in the pictures above. Reinforcing around a hole can help with clay, just like many other materials, this pattern and fix are similar to help many materials survive this typical stress concentration around a hole - pictured below. We reinforce all holes in flat plates with some added uniform thickness or washer if you will. Since, along with good practices no longitudinal cracks in these clock face figures.

OK so my current plan for the second bisque will be to fire it face up/grid down to 022 on slow, atop a very even layer of alumina (the L&L manual said not to use silica which is why I switched), possibly also on a waster slab on its own layer of alumina.
I may also use alumina and a bisqued waster slab for the eventual firing to 6.
Thanks all.