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neilestrick

Member Since 04 Oct 2011
Offline Last Active Today, 09:12 PM
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#66236 Repair Bisque Piece?

Posted by neilestrick on 16 September 2014 - 08:26 AM

Slow down the first several hundred degrees of your firing if you have thick spot like that.




#66109 Can A Candle Produce Enough Heat To Fuse Lid To Body?

Posted by neilestrick on 13 September 2014 - 11:54 AM

If the pot got hot enough in that area to melt the glaze, it would have been glowing, at least in that area. You can't get the inside wall of a pot that hot and not have the outside nearly as hot, too. The wall is not that thick. Even tack fusing glass needs 1300F degrees.

 

If the top of that pot was hot enough to melt glaze, the bottom would have been hot enough to burn whatever surface it was sitting on. In a 7 inch tall piece you could not get the top up to 2000F without the bottom getting up to at least many hundreds of degrees. Stick a 7 inch long tube of clay in the peep hole of your kiln till it glows and try to grab the cooler end. Plus the pot probably would have cracked if one spot was heating up that much.

 

Personally, I would not sell a candle holder with a lid. The odds of someone grabbing that lid while it's still hot are too great. Not only could they burn their fingers, but they could knock the thing over when they pull back their hand, spilling hot wax all over the place.




#65973 Kiln Lid Gap Help?

Posted by neilestrick on 10 September 2014 - 08:29 PM

Never set anything on the lid, especially heavy stuff. And never use a board as it can burn. And never use a battery because it can explode!




#65702 How To Get Started With Old Stains, Etc

Posted by neilestrick on 06 September 2014 - 01:36 PM

How do I mix small quantities of glaze? Everywhere I look the speak of 5 gallon buckets! To test the dozen glazes I have, I would like to make small batches of about 250 ml each. What ratio of water to dry glaze do I use?

 

For testing glaze I usually do 200 gram (dry weight) batches. Simply add enough water that it's the right consistency to dip a tile. The amount of water needed will vary from glaze to glaze. Use a stick/hand/immersion blender to mix it.




#65680 Questions About Firing With Peep Out

Posted by neilestrick on 06 September 2014 - 08:47 AM

If you're running a downdraft vent, all the peeps should be in whenever the fan is on.

 

You're probably right about the cooling time affecting the glossiness of the glazes. Slower cooling usually promotes matte surfaces. The vent will help speed cooling little bit, but you could always open a peep at the end of a firing to speed the cooling more. If your vent motor is mounted under the kiln, leave it running even with the peep open to keep the motor cool. If the motor is mounted away from the kiln you can turn it off when you open the peep. There will be a limit to how fast you can cool the kiln simply because it's bigger.




#65619 Gerstley Borate Subsitute

Posted by neilestrick on 04 September 2014 - 11:58 AM

Yep. Laguna has a bunch. But if you prefer a substitute, I'm a big fan of Gillespie Borate.




#65519 Is Is Possible To Calcine Your Own Kaolin?

Posted by neilestrick on 02 September 2014 - 08:44 PM

Once the chemical water is burned out, there's really not anything else that can happen to the kaolin. I suppose you could fire it so hot that it fuses, but what would be the point? Just bisque fire it and you're good to go.




#65477 Trouble With Dried Out Glaze

Posted by neilestrick on 02 September 2014 - 09:45 AM

You might also put the material in hot , almost boiling water to dissolve the soluble salts from the frit plus other stuff that may have formed.

Wyndham

 

That's exactly what I was thinking- 3134 has a fair amount of soluble material that has probably formed the chunks. It won't blend well.




#65312 Cost Of Replacing Elements

Posted by neilestrick on 28 August 2014 - 04:26 PM

APM elements last longer, however it's an expensive replacement if one fries due to a glaze drip or such.

 

I charge $75 per hour for repair work. A Skutt 1227 will take 1-1/2 to 2 hours to do a full element replacement. Definitely 2 hours if bricks are being replaced too, which usually there are a couple.

 

Different brands require more or less time. Skutts take a while because of the need for element pins, so in addition to the time spent putting in pins, I also have to remove the lid and top ring in order to reach the bottom ring and see what's going on down there. Paragon replacements are usually quicker because they only require pins if an element is being difficult, but some Paragon models have pricey elements. I can do all 9 elements in my big L&L in less than 1-1/2 hours. Manual kilns or any kilns that don't have a hinged control box take longer as well. Lots of factors at work.




#65215 Electric Kilns Now Described In Cubic Feet, Why?

Posted by neilestrick on 27 August 2014 - 01:43 PM

It also helps for bragging rights.

 

If ya say "I spent the week loading and firing my 200 cubic foot anagama kiln." it just sounds better than "I spent the week  loading and firing the big kiln."

 

A friend of mine built a duplicate of my gas kiln, except he built his one brick taller so that he could always brag that his was bigger.




#65205 Wood-Fired Turbo Kiln

Posted by neilestrick on 27 August 2014 - 12:27 PM

In grad school I mostly fired a cross draft wood kiln. It took 12-14 hours, burned 3 pickup loads of wood, and every pot came out snotty with ash. Wonderful kiln and easy to fire. I used 2 loads of  scrap lumber and 1 load of bark cuts from a local sawmill. The total cost of each firing was about $35 in wood. The key to that kiln was that the fire box was the same size as the ware stack. It was just a catenary arch with a bag wall in the middle and an ash pit under the firebox side. I've also seen it done with a barrel arch, which give you a little more stacking space. Either way it's an easy kiln to build and fire, and can be scaled to just about any size.

 

A single chamber cross draft wood kiln essentially fires just like a gas kiln. You have fuel, air, and a damper. The three work in conjunction to control the atmosphere and rate of climb. The only difference is that your fuel is not putting out constant energy like gas burners, but rather rising and falling with each stoke. But that's easy enough to deal with. If you understand how to fire a gas kiln, you can fire this type of wood kiln. It will take practice, of course, to get the results you want, but just getting it to temperature is not an issue. You can adjust the atmosphere, the pressure in the kiln, the temperature top to bottom, etc, just like a gas kiln.

 

A long time ago, the first wood firing I ever did was at John Balistreri's anagama (6' tall x 30' long) in Denver. It was an 8 day firing. He said he could actually get the whole thing to temperature in less than 24 hours, but there wouldn't be enough ash for anything to look good. So most of the firing was spent just burning wood to build up ash, and for the flame to work its magic.




#65122 Irregular Bowls

Posted by neilestrick on 26 August 2014 - 12:55 PM

I went to grad school with a fellow who made loose pots. We were the exact opposite of each other in terms of aesthetics. Anyway, he would throw a piece fairly tight to establish an even thickness, then do the last pull or two quickly and loosely. He would then often take a wire and cut the lip off in an undulating motion as the wheel slowly spun, then smooth and round the lip with a chamois. A smack or two the walls would knock it off kilter, and it was done. Very deliberate, controlled steps to give the appearance of looseness.




#65113 Irregular Bowls

Posted by neilestrick on 26 August 2014 - 12:02 PM

You've just made a very important realization. My students often make the remark "I could make that" when they see a piece in a magazine that is loosely thrown. But there is definitely a difference between poorly made and loosely made. Beginning students don't usually have the experience to tell the difference.

 

It's kind of difficult to explain, but I think the biggest difference is that loose pots look deliberate. Loose doesn't mean a lack of control during the making process. In fact, I'd say there's more control required to be able to handle the clay when it's not spinning perfect and even. It's easy to spot mistakes in throwing, because we've all made them before, so be very deliberate about your movements and do everything with intent.




#64957 Using A Kiln For Other Than Firing Pottery

Posted by neilestrick on 23 August 2014 - 12:39 PM

Anyone ever baked bread in a kiln?  Any toxicity concerns?

 

Is not a good idea to cook food in your kiln. A certain amount of the stuff that burns out of the clay and glazes is absorbed by or is on the surface of the kiln's bricks. It's a tiny amount, but you don't want that getting into your food.




#64945 New Kiln Questions

Posted by neilestrick on 23 August 2014 - 08:44 AM

Firing Cost

 

In your manual, in the 'Operation' section, are directions for the first firing in your kiln. You will be doing a Slow Bisque to cone 5 with a 3 hour preheat. This long, slow firing will season your elements and bricks, and set the mortar in the lid and floor. No need to put any furniture in the kiln- just leave it empty. After that you're set to fire some pots!