Rockhopper

Are you lifting the shut-off weight, and holding it in place while you put the cone on the sitter, or are you placing the cone first, then lifting the weight ? (Placing cone first would require forcing the outer end of the rod upward to get the weight behind it - which might put enough stress on the cone to cause a small crack before the firing even starts.)

I strongly recommend that you not use that plug - whether you twist it back, or not. There's a good chance that, in twisting it to its current shape, the connection between the blade of the plug, and the wires has been damaged or weakened - which could lead to arcing and overheating.

@Bill Kielb Thanks for doing the math, and sharing it! I don't see it mentioned - but I assume your tables are based on copper wire, since that's what is used in most situations - but, especially with larger wires and long runs (ie sub-feed from house to garage or other out-building), aluminum is still used for cost savings. A common example might be #2 aluminum SEU, running from house to garage. Could you give us a comparison of the #2 aluminum vs #2 copper for a 100ft run ?

I definitely understand that... I managed the electrical department of a local home-center for several years in the 90's... I still shake my head when I think about how many people would come in asking for a 30 amp fuse, because "the 20 that's in the box keeps blowing every time I turn the microwave on while the window air-conditioner is running". In my case, I already have a 40-amp circuit, and was trying to figure out whether if/when I buy a new kiln, I would need to install a 50A outlet on that circuit, to match the kiln plug - or maybe change the plug on the kiln to match the outlet. (If I were installing a new circuit, I would definitely use #6 wire - or maybe #4, depending on length - with a 50 amp outlet.) I've done a fair amount of residential wiring over the years, but most of it 15- and 20-amp 120v circuits, so less familiar with the 240v requirements. After thinking it through a little more, it looks like Paragon & others use a 50A plug in this situation because a 30A plug would not meet the requirement (somewhere in the code book) that the connector be rated higher than the actual load. And, since there are no 40A plugs or receptacles (at-least not in the NEMA standards), the next size up would be 50A ... (They spec #6 wire because that's the minimum for a 50-amp circuit.)

So... If I buy a TNF823, and already have a 30amp outlet, wired with #8 wire and a 40amp breaker - would I install a 50amp outlet, to match the plug on the kiln, even though the circuit is only wired for 40amps - or change the plug to match the outlet ? (Or, more importantly, if I change the plug to match the existing outlet, does that affect the warranty on the kiln ?)

Whether you use a disconnect, as Neil suggested, or an actual sub-panel, you're still going to be 50ft from the main panel - so the wire to get from there to the kiln will be the same. Only reason to put in a sub-panel, instead of a disconnect, would be if you want/need to add a separate circuit (i.e. for a kiln vent) in addition to the one for the kiln itself. In that case, it might make sense to put in a 4-space sub panel, instead of running both circuits from the main panel (especially if you don't have a lot of space in the main). Just make sure the wire feeding the sub, and the breaker that it connects to in the main, are sized to handle the total load that's going to be connected to the sub.

So... probably best not to re-use a cone with a new (un-fired) batch of pots - but I'm wondering: If one is re-firing an entire load because it didn't reach target cone... would re-using the original cones from that firing be a more accurate reflection of the total heat-work the pots in that particular kiln-load actually received ?

A plywood cart ? A kiln should never be in direct contact with anything flammable while it's in use. That said - some of the kiln makers sell wheeled metal stands, so there's nothing wrong with having it on wheels - as long as it's an all metal stand that's going to properly support the floor of the kiln. I have mine on wheels - so that I can move it out away from walls, etc. while it's firing, then tuck it away in the corner when it's not - but I'm just rolling it around within the garage. Moving it in & out of the garage might be a little iffy, depending on how flat the transition from garage floor to driveway is. Also keep in mind, it needs to be as level as possible while firing to minimize risk of pots (or shelve) falling over during firing. Depending on situation, moving it outside to fire could increase risk of a curious person or animal getting too close while it's hot... and, unless it's under a patio-cover or carport, you won't be able to fire if it's raining/snowing, or expected to be doing either, during the time it takes to fire.

You may want to try a multi-step process: Start by using alginate to make a mould from your original. Then, using the alginate mould, make a replica with either plaster or silicone (depending on what your final mould will be made with). Last, make your final mould with whichever material you chose, from the replica you cast with the alginate mould. It's a little more work, and time, but you greatly reduce the risk of damaging your original.

Have you double-checked that the hole(s) in the floor of the kiln is un-obstructed, so that your vent can actually pull air out of the kiln ? If it can't pull air out, you're not going to see any getting pulled in.

Polycrylic is a great product. So is the comparable water-based product from Varethane. But be sure to do some testing before you apply it to your finished piece. The flatter the finish, the more it will tend to dull your colors a bit. This becomes especially noticeable with multiple coats and/or over larger areas of black or other dark colors. I would suggest trying the satin first. Then, if it's still too much gloss, you could switch to the matte.

So does isopropyl (rubbing) alcohol.

It's a little hard to tell from the pic, but it doesn't really look like what I would call a "matte" finish - at-least not on the gold. To me, it looks like it's a shiny finish that's not on a perfectly smooth surface. Looks to me like the whole piece has a bit of an orange-peel texture to it, and looks like there may be some bubbles in the clear around the base of the raised area with the lustre on it. I think the lustre is just amplifying the underlying surface texture.

A piston-type air compressor is very much like a car engine, except backwards. With a compressor, instead of burning fuel to push the pistons and turn engine, an electric motor turns the 'engine' and the pistons push air into the tank. In a car, if oil seeps past the rings that seal pistons, it gets burned along with the gas & air coming in from the fuel injector (or carburetor). In a compressor, if oil gets past those rings, it gets pushed into the tank with the air, and can eventually find its way into the paint or glaze you're spraying.

Thanks for the clarification Bill. Guess that's what I get for trusting the store clerk's explanation of what the 'S' in SCFM stands for. So for a given PSI, a higher SCFM rating will provide more air than a lower one, but still not necessarily the volume that I am expecting it to provide .... and, when the label on a portable compressor says "2.6 SCFM delivered at 90 PSI", it is probably only going to give me that 2.6 CFM for relatively short bursts ? Guess it's a good thing I'm only using mine for nail guns, and adding air to a tire now & then.