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Member Since 04 Oct 2011
Offline Last Active Today, 02:31 PM

#60093 Noob Seeks Advice Building Kiln On The Cheap

Posted by neilestrick on 05 June 2014 - 09:23 PM

When you cook a pork roast, you can cook it at 350 degrees for an hour or 275 degrees for 4 hours. Either way you get a roast that's cooked to 170 degrees inside. The heat work is the same even though the temperatures were different. In a kiln, the temperature at which you achieve the heat work will primarily depend on how fast the kiln is heating up. Faster climb equals higher temperature to achieve the heat work.

#60062 Glaze And Oxide Question

Posted by neilestrick on 05 June 2014 - 04:14 PM

It will al depend on how thick it goes on. Too thick and you'll get a nasty matte wrinkly metallic surface. Too thin and it won't show up well. So keep notes on your water to RIO ratio and try several different applications.

#60041 Simple Runny Glaze

Posted by neilestrick on 05 June 2014 - 10:04 AM

I am intrigued by your request.  most public kiln owners would be horrified to find that someone deliberately put a runny glaze on a pot and it ran all over their shelf.  what is your purpose in using such a glaze?


Many of the glazes I mix for my students to use are runny. But I train them on how to use them so as to avoid ruining my shelves. Yes, I do have a few that stick in every firing, but most aren't very bad and clean up easily. And once they see how it can ruin their pots if they stick to the shelves, they are much more careful in the future.


Runny glazes make for very interesting surfaces.



#59962 Glaze Layering Using Different Manufactors Products

Posted by neilestrick on 04 June 2014 - 11:09 AM

Mixing manufacturers products is not a problem- the problems arise with specific glazes. Many product lines aren't even the same formula from color to color, especially in cone 5-6 glazes. Laguna's Moroccan Sand series is a good example of that. Lots of different base formulas in that series. So test, test, test every combination you can, even those that don't seem like they would work. Some of the best combos in my studio come from glazes I never would have thought to put together. You'll get some ugly ones, some great ones, and possibly some that even bubble and do all sorts of nasty things.

#59907 Ready Made Celadon Glaze For High Fire- Gas ...like Coleman

Posted by neilestrick on 03 June 2014 - 02:20 PM

Commercial glazes for cone 10 aren't nearly as common as for lower temperatures, but there are some out there. You may have a hard time finding them pre-mixed, though, because brushed on glazes at cone 10 generally come out looking pretty splotchy and uneven, since they tend to be very picky about thickness of application. You should be able to find some cone 10 glazes in dry form, though, which simply require mixing with water and sieving.


Just do  Google search and you'll find some options.

#59894 Can You Double A Wood Burning Oven As A Kiln?

Posted by neilestrick on 03 June 2014 - 12:21 PM

Yeah.... now that I've said all that.... I'm nuts.  Think I'll go get a couple big L+Ls with nice computerized controllers.  Sounds REALLY good to me right about now.  ;)






Give me a call. I accept Visa, MC and Discover.

#59685 Anyone Know Of Us Kiln Manufacturers That Do Anything Like This?

Posted by neilestrick on 31 May 2014 - 01:33 PM

Flame stratification on  the cheapie venturi burners that those hex conversion kilns or even the commercial hex gas kilns tend to use are SO reliant on secondary air. 


And yet those kilns have little to no chimney height to actually create the draw needed to provide that secondary air. Power burners are perfect for kilns with no chimney! For the price of the 2 to 4 venturi burners they typically use on the little round kilns, they could build a single power burner with the same or greater output. The real cost of burner systems is in the safety equipment- solenoids, flame sensors, etc.- not the burner itself.


The other great thing about power burners is that you can drastically change the orifice size without messing up the burner. So if you don't have enough power, you can fix it by increasing the orifice size (as long as you have enough gas volume coming in, of course). And if you find you need more air, you can put on a larger blower.


I think that many of the folks who convert the round electrics into gas think that because the round raku gas kilns work well, it should also work for a cone 10 reduction kiln. But the truth is that any crappy burner setup can get a raku kiln to temperature. 1850F degrees is easy. But as you get into higher temperatures the lack of insulation in those kilns becomes a real issue, as does the uneven temperature and atmosphere.

#59664 Duncan Da820-2 Good Choice For Beginner?

Posted by neilestrick on 31 May 2014 - 10:43 AM

If the bricks are in good shape then it's likely worth it. Take a look at the elements. They shouldn't look fried or rusted or brittle. Coils should be standing upright, not sagging down on each other. Open the control box and check the wires. They should be flexible and not crunchy when you bend them. If the the elements need changing it will cost you a couple hundred dollars. If the wires need changing it will cost tens of dollars. If you can plug it in and test it then do. Call Paragon and make sure it's a model they still have parts for. Try to get the down to $300 regardless!

#59601 Anyone Know Of Us Kiln Manufacturers That Do Anything Like This?

Posted by neilestrick on 30 May 2014 - 03:21 PM

Kiln shelves do warp from gravity and weight, but they also warp from uneven heating. The hot side expands more than the cold side, causing a warp in the shelf. Over time they don't go back to totally straight when they cool.

#59593 Anyone Know Of Us Kiln Manufacturers That Do Anything Like This?

Posted by neilestrick on 30 May 2014 - 02:31 PM

You could build a much larger kiln yourself for $6700US, and I wouldn't trust those rubber wheels to last very long being that close to the kiln. One potential problem is the kiln shelf they're using to separate the flue from the kiln. It's going to warp over time, and when it does it will crack the bricks that it's mortised into. Used to happen all the time on the old Alpine kilns that used kiln shelves as bag walls. They warped and cracked the door jam they were set into. I switched them to a brick bag wall when I was manager there.

#59526 This Is What Clay Looks Like From The Pug

Posted by neilestrick on 29 May 2014 - 09:08 PM

I have never seen clay go into laminations like that unless it was frozen at some point. If that's how it looks coming out of the pugger, then there might be something wrong with your pugger.

#59507 Does Any One Else Miss This Nutcase?

Posted by neilestrick on 29 May 2014 - 05:14 PM

There is a difference between things that are loosely made by skilled hands and poorly made by unskilled hands. However simple a piece may be, if it is made by skilled hands it will show an intent and confidence that unskilled hands cannot duplicate.


I had the opportunity to help fire John Balistreri's anagama in Denver in 1995. In that kiln were several pieces by Ken Ferguson and Don Reitz, as well as a Voulkos stack and several of his platters. The stack had already been sold to some company in Japan for tens of thousands of dollars. The platters were thick as can be, about 24 inches across, and amazing. We had a special surprise when Voulkos flew out to see the pieces when we unloaded. Really nice guy. He was clearly not in the best health at that time, but he was still making great work. And there was plenty of technical skill involved in their construction.

#59497 Metallic Weirdness On Pots

Posted by neilestrick on 29 May 2014 - 02:22 PM

Was the blue crud on the iron grate? Or did it just look cooked and flaky? It seems like if there was something vaporizing out of the iron then it would have also had an effect on the iron itself. It also seems unlikely to me that there could be enough of anything in the angle iron grate to cause issues throughout the kiln.


Different woods can have a huge effect on the firing. I grad school a friend of mine did his thesis on firing with cottonwood. It was a bear to split, didn't give off much heat, created a ton of ash that clogged up the kiln, and made everything look like varnished concrete- gray and glossy. He sent some ash off to the lab and found that the cottonwood in our area was really high in potassium, hence the gray gloss. After some experimentation he figured out that with a high iron body (4.5%), and adjusting the firing to account for the heavy ash, the results were fantastic, especially when reduction cooled. It did some awful things with some glazes, though, that firing with pine didn't do.


Try a different grate in the next firing, with the same wood source and see what happens. If it is the metal causing the issue, it will be interesting to figure out what exactly is going on.

#59293 Real-Time Kiln Advice (Kiln Curently Firing)

Posted by neilestrick on 26 May 2014 - 08:49 PM

Gosh this has been exciting!!!!!!   Makes cone 6 electric look boring!!!  


Boring, but she could have had a couple of loads fired by now! :D


All kidding aside, this is probably the most educational thread EVER!

#59099 Raku Party - How Can We 'do It Up Right'?

Posted by neilestrick on 23 May 2014 - 08:40 AM

If I have an event in my shop where I will be serving alcoholic beverages, like a gallery opening, am not allowed to advertise that there will be alcohol available. If I was charging admission to the event, the rules would change, and I would not be allowed to serve alcohol at all since I do not have a liquor license. So you'll have to check with your local authorities on how all that works. It may be different if it's BYOB.


The biggest concern for me when doing raku workshops is safety. I think the vast majority of raku workshops are done in an unsafe manner. Don't even get me started on the dangerous raku kiln designs. For all attendees, I have the following rules:


1. Long pants

2. Closed toe shoes

3. No synthetic fiber clothing

4. Safety glasses and gloves when near the cans.


For those who want to pull pots from the kiln, they have to wear the full gear- hat, face shield, long gloves, fire coat.


For me, Raku workshops are not a good money maker. Too many hours to make it worthwhile, plus gas and materials costs are high. I do it as a fun event to get people together who aren't normally in the same classes, and to bring some new students in.