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neilestrick

Member Since 04 Oct 2011
Online Last Active Today, 07:10 PM
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#111637 Can I Get Away Without A Test Kiln?

Posted by neilestrick on 18 August 2016 - 07:36 PM

Denise: are you getting the $25 cost from the COST function on the kiln? Just trying to figure out why my kiln is estimating costs so much lower. I fire to ^6.

 

When you calculate the cost of your electricity, make sure you're looking at your bill correctly. On my electric bill there are two different main charges, and several other small charges which go into the total- Supply Charge, Delivery Service, Taxes, etc. So if I just look at the cost per KWh, it won't be accurate. You have to take the total cost on the bill and divide it by the KWh used that month to give you the true cost of firing. That said, the cost of electricity can vary greatly around the country. Last time I checked, for it was just under 17 cents per KWh. I estimate my big 21 cubic foot electric to cost me around $35 per load, and I can get electric bills of close to $500 a month for my shop in the winter when the baseboard heaters are running, too. Thank God for budget billing! A 10 cubic foot kiln like a Skutt 1227 I would expect to be in the $12-20 range depending on where you live. A little 1 cubic foot test kiln should only cost a couple of dollars, so within 100 firings you could make up the cost over firing the big kiln empty.

 

Whether you end up getting a little test kiln or fire the big one empty, you'll need to put in a cooling cycle. An empty big kiln or a little test kiln will cool much slower than a full big kiln, and that will dramatically affect your glazes. It doesn't necessarily have to be a 'slow' cooling, but something that will be consistent in all firings. You should set it to cool from the peak temperature, since crash cooling from the top will also be different in each situation. I cool at a rate of 175/hr down to 1500F, which takes about 3 hours. My big kiln hardly clicks on at all during that cycle once it gets down a couple hundred degrees, and I get identical results from all 3 of my kilns. My test kiln cools so quickly that many glazes come out really bad if I don't slow down the cooling.




#111630 Reduction Fire ^5/^6 Gas Length Of Time

Posted by neilestrick on 18 August 2016 - 05:14 PM

If you don't reduce at the low end, cone 012-06ish, the clay and glazes will be sealed over and the reduction won't penetrate into the clay. That's why they call it body reduction, it reduces the clay body. Reduction at the high end can have an effect on glazes, but in my experience it's minimal. With some glazes, like american shino glazes that are high in soda ash, the soda ash that has precipitated to the surface will melt out very early and seal off the the glaze, preventing good reduction, so they have to be reduced very early, like 014-012. Once you reduce at the low end, it doesn't really matter much how the firing goes from there. You can fire neutral or reducing the rest of the way up. Once it's reduced, it's reduced, but it has to be done at the low end.




#111566 Black Grime On Wheel Head When Throwing?

Posted by neilestrick on 17 August 2016 - 08:51 PM

That's a relief. If it gets mixed in with clay scraps, it imparts a grey hue to the clay. Will this affect the final colour after firing?

 

Nope.




#111549 Black Grime On Wheel Head When Throwing?

Posted by neilestrick on 17 August 2016 - 04:53 PM

It's just the clay abrading the aluminum head. No biggy.




#111462 Additives For Old Glazes

Posted by neilestrick on 16 August 2016 - 11:21 AM

It's easiest to use gum as a solution when first mixing the glaze. You can do it from a wet mixed glaze, but there's a little more trial and error. I would do this:

- Take a gallon of glaze and add a teaspoon of CMC gum and a pinch of copper carbonate (preservative) to it. Stir it in and let it sit overnight. The next day, use an immersion blender to blend it smooth. You may have to add a little water to it if it gets too thick. Then brush it onto a pot to see if it works. If it's still not brushable enough, add another teaspoon of gum and repeat the process. If it's going on too thin, then you need less gum. Once you figure out how much gum does the trick in a gallon, you can calculate out how much you'll need for however much glaze you have in the bucket.




#111212 Going Gas, Need Some Direction

Posted by neilestrick on 10 August 2016 - 05:58 PM

Yep, you're getting into a very complicated situation. Start with the gas company and the local zoning rules before you even begin looking at kilns. Business vs. hobby is a big deal, and will dictate much of what you can and cannot do.  Where I live a gas kiln is out of the question either way. Venting a gas kiln is much more complicated than venting an electric kiln, and going out the window will likely not work. You'll either need to go out the roof with a natural draft vent, or out the wall with a powered vent. A vent hood system can cost thousands.

 

There's a lot you can do in oxidation, including much of what you can do in reduction. The simplicity and low cost of setting up and electric kiln may be worth it. You should also check into firing costs. Around here it's a lot cheaper to fire electric.




#111187 Liability Of Making Lamps?

Posted by neilestrick on 10 August 2016 - 09:16 AM

I've sold many lamps, and never worried about the liability. I use UL listed sockets, and construct them so the cord can't pull out. I don't think you'll sell many if the customer has to wire them up.




#111157 My Kiln Build

Posted by neilestrick on 09 August 2016 - 02:38 PM

Just go with what you've got. It won't make a difference. The whole cube thing is not a requirement. I've built and fired many kilns that are rectangles. It's all good. Don't over think it.




#110524 L&l Kiln Or Skutt?

Posted by neilestrick on 25 July 2016 - 11:27 AM

What ever you do do not buy an L&L kiln. I have one and will never own another L&L product again. It is unbelievably poorly built. Even with the heavy duty elements my e28T-3-240 CANNOT get to cone 6 when fully loaded. I bought it for a glaze kiln but only use it to bisque and even at that I use only 3 levels. I just purchased their kiln wall replacement kit. I followed the directions, put my pieces of kiln wall in place and there was no adhesion whatsoever. I did it again, using more moisture. Seemed to work. I fired the kiln, as per instructions and the pieces had fallen out. Utterly useless. The control box is mounted off kilter, the kiln arrived with cracks everywhere and in fact the entire piece is a piece of crap. I also have a Skutt and a Cone Art kiln and they are both great. My next purchase will be a Skutt PK kiln. I cannot condemn sufficiently the L&L products. They disgust me.

 

Yes, L&L does admit that the E28T is underpowered, and they are very clear about it in all of their literature. That said, I have many customers who fire their E28T to cone 6 every week with no problems. They are on 240V single phase power, and even though it's a cone 8 kiln, it handles cone 6 just fine. There's obviously something going on with your specific kiln, or you're loading it with very dense loads which it just can't handle. It's also possible that you have a low service voltage problem or something like that. I'd be happy to work with you to try to figure out the problem. What year was your kiln made?

 

This is not just an L&L issue, though. Any 28x28 inch kiln that only pulls 48 amps, whether it's an L&L or Skutt or Paragon or whatever, will only be rated for cone 8 at 240V 1 phase service, or cone 5 at 208V 1 phase. These models are all part of their 'plug and play' series', where you don't have to hard wire them. Anything over 50 amps has to be hard wired. The L&L E28T and the Skutt KM1227 have the exact same temperature ratings.

 

If you want more power in a large kiln like that, you'll need to go up to an 80 amp breaker, which requires hard wiring. All brands offer higher power models like that. The Skutt PK is one example, but all brands make higher powered models. And you can't compare a Skutt PK to an L&L E28T or Skutt KM1227. That's apples to oranges.




#110364 Tips On Using Porcelain

Posted by neilestrick on 20 July 2016 - 09:14 AM

Ditto what Marcia said. Work quickly, as it absorbs water much faster than stoneware. Standard 365 is a wonderful cone 6 porcelain, one of the best throwing porcelains I've used. I've made 45 pound planters with it without any warping or cracking.




#110052 Do You Wrap Your Tools To Make Them More Comfortable To Hold?

Posted by neilestrick on 12 July 2016 - 09:21 PM

my hand therapist talks about a product you can coat your tools with so they are like those "soft " pens you sometimes see. No clue what it is but wish i had some.    rakuku

 

http://www.homedepot...603-6/202196703




#109995 Correct Camera Lens For Product Photos?

Posted by neilestrick on 11 July 2016 - 03:17 PM

Lighting is more important than the camera. Just about any phone camera can work. An SLR is not necessary. A decent camera with a zoom lens would be the most versatile for shooting small pieces or groupings. You really can't go wrong nowadays with any major brand, as the quality of even lower end models is plenty good for web shots. Good lighting can be had with daylight, or a cheap lighting setup can be built or purchased for $100 or less. Making good product photos has never been cheaper or easier.




#109583 Ceramic Ink, Crayon And Underglaze

Posted by neilestrick on 28 June 2016 - 08:41 PM

In my opinion it's not worth making your own underglazes. Commercial underglazes are plentiful, work very well, and can be purchased relatively cheaply, especially when they go on sale. In addition to all the testing that will be required to get a homemade underglaze to work the way you want it to, it will take numerous rounds of testing to work out the colors and a lot of wasted money buying stains that won't be right. Plus underglazes are saturated with colorants, and it may not be all that much cheaper to make your own once you factor in the cost of the stains, especially reds and oranges.

 

I use Speedball brand underglazes. They are quite cheap and work very well. Sign up for the newsletter at www.Clay-King.com and watch for their sales. Several times a year they'll have Speedball products at 40%-50% off, which gets them down to about $6 per pint or less, and they usually need to be watered down a bit so it's a really good deal.




#109533 Corbels

Posted by neilestrick on 28 June 2016 - 10:06 AM

I would make it decorative, not structural, no matter what type of clay you use. You could design it to cover a structural member. Use construction adhesive to mount it. A groggy body would be most forgiving, or paperclay.




#109319 Crazing - Commercial Glaze

Posted by neilestrick on 24 June 2016 - 10:50 AM

You can do the same test by adding the silica and kaolin to a specific amount of wet glaze, then calculate it out for the big batch. I would take a pint of wet glaze and test increments of 5g each silica and kaolin up to 25 grams each. That will likely fix this batch, but you'll need to run new tests with dry material for the next batch.