neilestrick
-
Posts
12,450 -
Joined
-
Last visited
Content Type
Profiles
Events
Forums
Blogs
Gallery
Posts posted by neilestrick
-
-
3 hours ago, kevinpleong said:
Yes and no. My understanding is that there are many commercial cone 6 clay that technically are not fully vitrified. They still allow them to be produced but they still technically have up to 2% absorption.
I said 'properly formulated'. There are commercially produced cone 10 bodies that have greater than 2% absorption, too. There is nothing about cone 10 that makes work any more durable or functional or safe to use. It's just hotter. That's it. Regardless of the temperature you're firing at, you can make vitrified, durable, safe pots.
-
I've always used the SUV I drive everyday. For the last 7 years that has been a 2012 Nissan Pathfinder. Before that a 2011 Chevy Traverse. Before that a 1998 Pathfinder which was a little smaller than ideal- I had to strap stuff to the roof rack. Some use vans, some use pickups, some use a trailer. Deciding what works best for you depends on your booth setup, how much work you'll be taking to shows, costs, etc. HERE is a little article I wrote on the subject.
-
7 hours ago, kevinpleong said:
The only problem is they have an oxidation and reduction kiln but the glazes are very dark and mostly browns in the reduction kiln. I am not sure whether this is because of the glazes or the way they fire the reduction kiln.
Probably a combination of their glaze choices, firing technique, and clay choices.
7 hours ago, kevinpleong said:I appreciate cone 10 because the clay is completely vitrified at that point.
Cone 6 clays are also vitrified. There's no difference, assuming both are properly formulated.
-
4 hours ago, mandyk said:
Thanks everyone! Since I'm a newbie... can you now help teach me if there's a way to mark the issue resolved? I understand that it might be helpful to someone else to read about further down the road, but you've helped me figure it out, and I don't need any more responses. I know I can unfollow the topic, but I don't want to waste anyone else's time on writing up more responses
We don't have a way to specifically mark it as resolved, but I think this statement will do it. Glad you got the answer you needed!
-
-
The glass has a very different COE (coefficient of expansion- different shrinkage) than the clay and glaze, and it most likely put a ton of stress on the coasters and blew them apart.
To get the piece off the bottom, try sliding a pallet knife/scraper under the chunk. You may lose a little bit of the floor but that won't hurt anything. If it has melted into the floor a bit, put a thick layer of kiln wash on it for the next few firings until it stops melting.
-
In addition to the potential band issue, if the outer dimensions are not the same then your control boxes are not going to line up properly. I also think it's going to affect how the kiln heats. If you had zone control it wouldn't be an issue, but with just one thermocouple the 2 1/2" section is likely to run colder than the 3" section. Plus the overall energy savings would be minimal since the lid and floor would still be 2 1/2" brick.
What does it say on the serial plate for the max temp rating of the kiln? If I remember correctly, the 181 is only rated to about cone 5/6, which is the biggest reason it's struggling to reach cone 6. You're maxing it out, and you're not going to get very many firings before it won't reach cone 6 at all, like maybe only 30 firings.
-
There's a lot of leeway in these lid braces. If you're a few inches either way it's not going to matter.
-
-
The slip has not moved. The color of the brown clay is coming through the slip where it is thin. You need more coats of slip.
-
Those dangling elements should be replaced, otherwise they're going to contact the work in the kiln and cause problems. You'll also have to replace those broken bricks or else the elements are just going to flop out again. Neither is super difficult, but if you've never done it before it'll take some time. You'll spend $65 per element and about $17 per brick to fix it. HERE is a video that shows how to replace bricks. HERE is a video showing how to replace elements.
I would pass on that kiln if you don't have experience with repairs. If I remember correctly, the 231 has the old style control boxes with the early generation Kiln Sitter, which is not ideal, and not easy to work in.
-
-
The simplest and most affordable way to fire is with an electric kiln. They are easy to use, easy to set up, can be installed in basements and garages and studios. They don't take up much room and are easy to vent. Firing to cone 5/6 you'll have durable, vitrified pots for food use, and there are hundreds and hundreds of commercially available glazes.
What type of kilns are used at your studio?
-
@mandyk The arm piece attaches to the lid directly above the prop, so that the arm hangs straight down in the prop frame when the lid is closed. Both attach to the left side of the kiln as you look at it, 90 degrees from the center of the hinge. THIS VIDEO shows the placement. Also THIS.
-
14 minutes ago, cadenrank said:
You're referring to the circuit rating that the breaker would cover, when you say 50 amps? As in, even if the kiln wouldn't pull that? I understand the >125% <150% rule, but am just verifying that it does or does not apply to the conductor as well. I wish I would have run 6 gauge when I originally did the project like I did with my other kiln, but originally this kiln only pulled 24 amps, so I never thought I'd need the extra amperage there.
Anyways, I plan to keep this kiln near 30 amps, I mostly just thought it was odd that skutt recommended 8awg and a 50 amp breaker for that specific model of kilnThe wiring should be rated the same as the breaker.
-
@cadenrank When looking at a wire ampacity chart, it's safest to use the largest wire size number for that amperage, regardless of which type wire you use, which means that for 50 amps you need 6 gauge wire. Always better to over-build.
(Edited for better wording)
-
-
Can you describe the debris? If it's white chunks in your glaze, it's either kiln wash flaking onto your pots, or bricks flaking. Does it only happen on the top shelf? Is there any wash on the bottoms of your shelves?
You can't really stop cobalt from fuming. You might try putting more space between the top of your plates and the bottom of the shelf above them. I've never heard of it fuming the bottom of a shelf, so I think it's just too close.
-
If it's a round kiln then it most likely does not have any of the dangerous stuff, as they are pretty simple construction- bricks cut at an angle with a steel band holding them together. There are some models that use some fiber insulation behind the bricks but those are uncommon in round kilns and easy to spot. If it's a square/rectangular kiln, then it most likely does have insulation of some sort behind the bricks. In a kiln that old it could be something harmless or something dangerous. In those cases just keep everything together and if the bricks ever need replacing, don't do it.
Post some pics. Sounds like it may not have a Kiln Sitter shutoff device.
-
36 minutes ago, DansCustoms said:
I have a kiln from 1957. Nothing looks broken at all. Tag say D.H.C Kiln. 230volt 25 amps. Is it safe to just fire it up?
If it has all the original wiring, maybe not. There's a good chance the wire insulation is pretty crispy and brittle. Give it a good inspection and see if the wires are still soft and pliable. If they're crispy and crunchy when you bend them, I'd replace the wiring. Power cord included.
-
That form is going to sag no matter how it's made. You either need to fire it low enough that the clay doesn't soften up, so at least a few cones lower than its maturation point, or you need to support the middle dips. You could just do a couple of little dimes sized unglazed spots on the bottoms of the dips where you could put a bit of clay to support it in the firing. If it's the same clay as you made the piece with then it's going to shrink with the piece.
-
4 hours ago, High Bridge Pottery said:
Tried mixing up another slip with half of the Kentucky clay but it just turned into a solid mass when I tried to deflocculate it
Think I must have added too much but I thought it would settle out not turn into a solid mass.
If you over-deflocculate it goes the other way. Kinda like chocolate seizing. Been there many times...
-
On 12/7/2022 at 2:50 AM, High Bridge Pottery said:
Never heard of reduction cooling before, I will take a look at the photos.
When you reduce an iron bearing clay body, the iron goes from red to black, and then the surface reoxidizes during cooling. If you cool in reduction, then the iron stays black. You need a clay body with 4-4.5% iron if you want black. To do it well, you need to be able to seal off the kiln but still be able to introduce a small amount of reduction. In a wood burning kiln, that means sealing up all the air holes with clay, and tossing in just a couple small scraps of wood every 10-20 minutes as it cools, down to a temp where it won't reoxidize. Very slow and boring process. In a gas kiln you seal off the burner ports but leave a small pilot flame burning for the reduction. Introducing small amounts of air can result in bright flashes of color on the surface. The first photo below is a teapot by John Neely, who pioneered reduction cooling in the US at Utah State University. It's not black clay, it's reduction cooled brown clay. The second is a piece by Susan Harris of Southern Utah University. Susan is a master of getting bright flashing in her reduction cooling pieces.
-
1 hour ago, Piedmont Pottery said:
I have the L&L eFL2635. It's a great kiln. The 3-phase 240V version needs a 70 AMP breaker. And you will likely need a forklift to move it into place.
The newest design of the eFL series ships the kiln body sitting directly on a pallet. It can be unloaded with a pallet jack, however you'll need a high lift pallet jack for assembly. You assemble the stand, lift up the kiln with the high lift jack, connect the stand, and set it all down. It's pretty simple, just takes a little time to get everything together.
Think I must have added too much but I thought it would settle out not turn into a solid mass.
Super matte glaze?
in Clay and Glaze Chemistry
Posted
A good magnesium matte glaze with a slow cooling can give that surface.