neilestrick

Hi Llama,
Welcome to the Forum!
I'm curious if the Artista has a brushed motor, and if so, are the commutator and brushes clean and in good condition?
...I like Neil's idea better tho'.

I've never seen that before. My gut says it's probably a bad potentiometer (speed control).

All very good reasons to work with low fire clay!

If the recipe call for volume, then do it that way.
Measuring by weight will generally give you a more accurate, repeatable mix. Because powders can be fluffy or compacted, you can get different amounts each time you measure by volume. Measuring by weight eliminates that variable. This is why so many baking recipes call for 'sifted' flour (sifting gives the flour a more consistent density for measuring by volume), and why professional bakers measure everything in grams.

Thank both of you for responding - looking to make highfire claybody.  I full understand the accuracy of weight over volume, but with the recipe as listed it would be a wildly different formula on weight versus volume, that is why I questioned it.  I was just not sure when I see recipes listed as "parts" if it was weight or volume in general unless otherwise specified.  Again - thanks for the responses.  New to the art and trying to learn.

Keep in mind that Pinnell's test was just one of several different types of tests that could be done to determine the strength of clay, and that most clay bodies are plenty strong for what we do with them. If strength was really an issue then we'd all be using low fire red clay, yet it's one of the least used bodies there is among ceramic artists. And although grog weakens bodies, it's still used in a large percentage of stoneware bodies because it has other benefits and doesn't weaken it enough to matter. Pinnell's tests are incredibly interesting and the results surprised most of us, but they're more academic than practical for the typical potter. The far bigger issues when determining the strength of a piece are the form, thickness, and construction technique. Little fingers on a figurative sculpture are going to be easy to break off regardless of what type of clay body you use. We select clay bodies based on firing temp, texture, and color, not MOR test results.

If it's an indoor sculpture, any clay body is strong enough regardless off the firing temp. How you pack it is much more important. In terms of deciding how hot to fire, that will depend on what types of surfaces you're after, and what materials are needed to achieve that. You'll also need to consider the shape of the piece and how the clay will respond to different firing temps. Porcelain is more likely to warp and sag when fired to maturity, low fire temps won't have that problem.

Hi @Lilya, welcome to the forum!
To make a glaze brushable:
Mix 2 tbsp CMC and 1/4 tsp copper carbonate with 1 gallon of water. Let it sit overnight, then mix well with a submersion blender. When mixing your glaze, substitute the gum syrup for about 1/3 of the water.
I would probably toss the current glaze. Sounds like you've messed with it enough that you can't save it.
The classic 80/20 raku white crackle glaze is just a clear glaze. It was popular because Gerstley was cheap and it suspended very well. The reason it crackles is because of the thermal shock. You can get the same effect from a low fire clear glaze like a simple 90 Frit 3124 and 10 EPK. Just like the original 80/20, you need to apply it somewhat thick to get good crackle. Having some clay in the recipe will make it suspend and brush better than a frit /neph sye blend.

HERE is a possible solution. Or HERE.  Definitely try the Frit 1254 you mentioned, but it's closer to Ferro 3134 than 3124, so it may not work as well.

What you've got there is crawling, not crazing. Crazing is when the glaze crackles. The problem is likely from the underglaze being applied to thickly as Min said.

The Shimpo Whisper and Pacifica GT wheels all are within your budget, and are good wheels that will work for what 99% of potters make.
IMO, Brent wheels last forever, but so do most wheels, and most wheels have better control than Brent. I own 9 Skutt wheels and they all have far better pedal control than Brent. And Brent replacement parts are pricey.

I'm with Bill. Making people calculate volume is a big pain for everyone involved. Asking most people to do that sort of math is not a good idea. Weight is a much easier way to do it, and you can easily have different pricing categories for big wide pieces like serving bowls that take up a lot of volume without much mass, and cups and such that are more compact. Or better yet, just include glazing and firing costs in the price of the clay. It keeps students from feeling like they're getting nickel-and-dimed to death, takes away a cumbersome step in the process, and makes it easier for people to  track and budget their pottery class spending.  I've done it by weight from day one, and it works fine. It's easy enough to figure out the approximate weight of clay in a typical load and calculate all the associated costs of firing and come up with a price. Plus it motivates people to throw thinner with less trimming, and makes them think more about the technical aspects of clay work like avoiding cracks and warping and whatnot that may keep the piece from getting fired.

We charge by weight at the centre.  Plus a little extra for some glazes, or a little less if only once fired.  

I'm with Bill. Making people calculate volume is a big pain for everyone involved. Asking most people to do that sort of math is not a good idea. Weight is a much easier way to do it, and you can easily have different pricing categories for big wide pieces like serving bowls that take up a lot of volume without much mass, and cups and such that are more compact. Or better yet, just include glazing and firing costs in the price of the clay. It keeps students from feeling like they're getting nickel-and-dimed to death, takes away a cumbersome step in the process, and makes it easier for people to  track and budget their pottery class spending.  I've done it by weight from day one, and it works fine. It's easy enough to figure out the approximate weight of clay in a typical load and calculate all the associated costs of firing and come up with a price. Plus it motivates people to throw thinner with less trimming, and makes them think more about the technical aspects of clay work like avoiding cracks and warping and whatnot that may keep the piece from getting fired.

I'm with Bill. Making people calculate volume is a big pain for everyone involved. Asking most people to do that sort of math is not a good idea. Weight is a much easier way to do it, and you can easily have different pricing categories for big wide pieces like serving bowls that take up a lot of volume without much mass, and cups and such that are more compact. Or better yet, just include glazing and firing costs in the price of the clay. It keeps students from feeling like they're getting nickel-and-dimed to death, takes away a cumbersome step in the process, and makes it easier for people to  track and budget their pottery class spending.  I've done it by weight from day one, and it works fine. It's easy enough to figure out the approximate weight of clay in a typical load and calculate all the associated costs of firing and come up with a price. Plus it motivates people to throw thinner with less trimming, and makes them think more about the technical aspects of clay work like avoiding cracks and warping and whatnot that may keep the piece from getting fired.

I tried to order some Skutt/TS wheel pedal potentiometers and was informed that they have redesigned the pedal and are no longer selling the old potentiometers. I did a little digging on the internet and found that the old potentiometers are no longer made, and there is not a direct replacement ( they were not made by Skutt). Seems they were forced to redesign the pedal to use a different potentiometer. A new pedal assembly costs $375 list. Luckily, the old potentiometers last forever. I've got 11 Skutt/TS wheels and have only ever had to replace 1 potentiometer in 20 years. But if you're worried, you might want to try to find  one somewhere to have in stock should it die.

I'd be mad. They should have installed the outlet to match your kiln, not modify your kiln without asking you. It's pure laziness, and because they modified it, they may have voided the warranty and/or UL listing. Make them replace the outlet with a 6-50 and make them buy and install a new power cord.

This is where it can get confusing. The Pacifica, Speedball, and Shimpo ratings are for how much clay can be centered on the wheel, which is when it's under the greatest load and torque really matters. The Brent B rating is how much clay the wheel can handle with it just sitting on there spinning, not under a lot of pressure. For some reason Brent stopped advertising their centering capacity and started using what they call 'continuous' load a few years back, probably just because '150 pounds continuously' sounds more impressive than '25 pound centering capacity'. So you have to pay close attention to what they're saying. Any wheel can handle simply rotating with way more clay sitting on it than you'll ever actually throw. What matters is its ability to maintain speed under heavy loads like when centering,  or maintaining consistent slow speeds like when working out at the edge of a large bowl or platter. Most wheels can be made to work just fine with some adjustments to your throwing style, but in general a bigger motor makes it easier. That said, most of what most potters make is under 5-6 pounds, which just about any wheel can handle without any problems.

The Shimpo Whisper and Pacifica GT wheels all are within your budget, and are good wheels that will work for what 99% of potters make.
IMO, Brent wheels last forever, but so do most wheels, and most wheels have better control than Brent. I own 9 Skutt wheels and they all have far better pedal control than Brent. And Brent replacement parts are pricey.

If you bisque fired to cone 6, then your clay is no longer porous and will not accept glaze well. You need to bisque fire to a much lower temperature like cone 04. That will harden the clay but it will still be porous for glazing.

The Shimpo Whisper and Pacifica GT wheels all are within your budget, and are good wheels that will work for what 99% of potters make.
IMO, Brent wheels last forever, but so do most wheels, and most wheels have better control than Brent. I own 9 Skutt wheels and they all have far better pedal control than Brent. And Brent replacement parts are pricey.

I would get the larger kiln. 8 sided kilns are fairly limiting in what you can fit in them.
You can get a wall mounted digital controller from Skutt or others, which basically turns your kiln into a digital kiln. You'll still have to turn on the Sitter, but the firing will be controlled by the digital system. They're not cheap, but you'll still be saving about $1500 vs the cost of a brand new kiln.
With a used kiln, make sure the bricks are in good condition- only small chips, no large breaks. Also check the lid and floor for cracks that go all the way through. Hairline cracks are normal. Also, if the bricks are very yellow in color then that's a sign that they've been fired a lot and are near the end of their life. White/cream colored bricks are what you want.

It all depends on how much it's been fired. I've got a 40 year old kiln in my studio that's never been fired, and I have a 13 year old kiln that's been fired more than 2200 times. The kiln in your photos looks great, assuming the lid and floor slabs are not cracked.

I would get the larger kiln. 8 sided kilns are fairly limiting in what you can fit in them.
You can get a wall mounted digital controller from Skutt or others, which basically turns your kiln into a digital kiln. You'll still have to turn on the Sitter, but the firing will be controlled by the digital system. They're not cheap, but you'll still be saving about $1500 vs the cost of a brand new kiln.
With a used kiln, make sure the bricks are in good condition- only small chips, no large breaks. Also check the lid and floor for cracks that go all the way through. Hairline cracks are normal. Also, if the bricks are very yellow in color then that's a sign that they've been fired a lot and are near the end of their life. White/cream colored bricks are what you want.

You won't get all the elements glowing unless it's on high.
Get yourself an inexpensive digital pyrometer and a heavy duty (8 gauge) type K thermocouple from Amazon and stick it in the spy hole to track temperature rise.