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Member Since 04 Oct 2011
Offline Last Active Oct 08 2015 08:02 PM

#91531 Proper Reduction Firing Schedule

Posted by neilestrick on 27 August 2015 - 02:44 PM

A reduction soak is not necessary at the end of the firing. If you haven't achieved reduction by then it's too late. For some glazes, however, it helps to do an oxidation soak at the end. I used to do it for my copper reds, as it cleared any muddiness out of the edges where the glaze breaks to white.


Get up to body reduction temps- cone 012 to 08- as quickly as you can while not cracking any pots and maintaining evenness. No sense wasting gas with a really slow climb if everything has been bisqued. Put the kiln into reduction at cone 012-08, and stall out the climb. Hold temperature with the reduction for 45 minutes. If you're trying to carbon trap a shino glaze, then make this a heavy smoky reduction. Then put it into a neutral atmosphere and let it climb to cone 10. Stalling it out in reduction will ensure that you get good reduction throughout the kiln, and climbing in a neutral atmosphere will give you an efficient use of gas.

#91402 Lead Glaze Recipes (No Safety Lectures Please)

Posted by neilestrick on 25 August 2015 - 08:05 PM

Sodium Uranate is a sodium salt of an uranium oxyanion (uranium oxide polyatomic ion) commonly called yellow uranium oxide.  Again, my acquisition of this material is through a personal connection.


Like the stuff they enrich for nuclear power? You must know some important people.

#91219 I Love This Forum! Throwing Clay Question (Noob)

Posted by neilestrick on 21 August 2015 - 12:35 PM

Stiffness and plasticity are two different issues. If the clay is stiff, that simply means that it has less water in it. You are at the mercy of the clay supplier as to how much water they put in their clay bodies. It will vary from batch to batch, as there is a range that they find acceptable. You can add water by poking the clay full of holes and putting it in a plastic bag with a little water for a few days. Then you have to wedge it.


Plasticity has to do with the formula of the clay body. Porcelain bodies are the least plastic, as they are very low in clay content by comparison, and the clay that is in them is not very plastic. If you need more plasticity you'll need to switch bodies.


As for that video, it's impossible to tell how stiff or plastic that clay is by watching. Any professional potter is going to make it look easy regardless of the qualities of the clay body he/she is using.

#91198 1800 Degrees....looking Good.....snap, Sparkle, Fizz, Pop. Dang!

Posted by neilestrick on 21 August 2015 - 08:46 AM


Old sitters can be full of corrosion. I suggest taking it out, taking it apart and cleaning the contact plates (the parts that connect when you push the power button) with fine sandpaper or a wire brush. Just last week I had to clean one out where the plates were so corroded that one leg wouldn't power up. Also clean all the terminals. Wet all terminals and screws with WD-40 and use a wire brush. Get everything shiny! Make sure you're using large enough wires to the switches.

Oh, this old kiln is no stranger to corrosion, Neil. I just underestimated  what under-torqued corroded fittings could do. Speaking of fittings, they should all be stainless. RIght? I'm guessing that the crimp-on ring connectors from auto parts place would not have the correct finish. Kind of hard to find serious fittings and ring connectors locally.



Use stainless for hardware like screws and washer and such, but I don't think you'll have a very easy time finding wire terminals that are stainless, nor do I think it's necessary. You'll get corrosion from the end of the wire anyway. I use high temp terminals, but I've seen many kilns with standard hardware store terminals and they seem to work fine.

#90943 What To Look For In A Used Kiln?

Posted by neilestrick on 16 August 2015 - 08:46 PM

As mentioned above, you're going to have a hard time finding one with a digital controller. When they do come up they are typically near new, like they bought the kiln and never used it. They are usually priced like a discounted new kiln, so not exactly a bargain unless you happen to be in the market for a new kiln.


You can find lots of goo manual kilns, though, and can always hook up an external digital controller for around $500-600.


When looking at used kilns, check that the bricks are good condition. If they are beginning to yellow, that's a sign that they have been fired a lot and will wear out sooner than later. If the element coils are all standing upright and the wire looks to be in decent condition, then there's a good chance the elements will work for a while longer. New elements will cost roughly $50 per element to replace them. The wiring in the control box is cheap to replace, but if you're not comfortable with doing it yourself, then open up the box and make sure it looks good. Bend the wires and see if they're still flexible. If they crunch then they're old and need replacing. If the connections are corroded then they need replacing. If the boxes have inter-box plugs, take the kiln sections apart and check for corrosion. Those plugs go bad a lot, and can be replaced by hard-wiring the sections. Get a brand that is still in business.


Get a Craigslist app on your phone that will store searches and set up a kiln search. Check it 3 times a day. If a good deal comes up it will go fast.

  • Min likes this

#90886 What Mesh Sieve Do You Screen To For Dipping Glazes?

Posted by neilestrick on 15 August 2015 - 08:39 AM


I have always sieved to 80 mesh. No problems. The finer the particles, the easier they melt. However the screen isn't reducing the particles size of the materials, it's breaking up clumps. Enough mixing and you don't need to screen at all.

So screening is not  necessary if you mix well, say with a stationary blender or stick blender? Are there other mixing alternatives that would be satisfactory for larger volumes?  What is the largest batch you would use a stick blender on?



I've used the stick blender on 2 gallon batches before. It takes a few minutes, but it's less cleanup than two buckets and a sieve. A blender is a high shear device, so it does and excellent job of getting rid of clumps. A drill mixer does not do nearly as good a job because it does not run at high RPMs, and the mixing blades are not made to cut, but rather just to move the material around, so it would take much longer to get it smooth that way.

#90841 Pie Dish Dilemna - Rough, Porous Clay

Posted by neilestrick on 14 August 2015 - 02:56 PM

Get some 220 grit wet-dry sandpaper (the black stuff) at the hardware store and wet sand the bottom of the pot until it is very smooth, and stops shedding. Let it dry, and see if it continues to shed.

#90722 Fire House

Posted by neilestrick on 12 August 2015 - 10:39 AM

The only issue with a kiln in the basement, assuming everything is set up properly, is the heat coming off the kiln. Depending on the size of the kiln, it can really heat up the room the kiln is in, as well as the room above. You'll want to figure out a way to remove that heat, either via a fan in a nearby window, or by using an overhead vent hood.

#90713 Fire House

Posted by neilestrick on 12 August 2015 - 09:00 AM

You could just have a roof with metal.No walls. When you are not firing you cover your kiln with a tarp.



Using this method, the structure would have to be large enough that blowing rain or snow couldn't reach the kiln. If a storm blows in while the kiln is hot, you can't cover it with the tarp. You're also likely to trap moisture and get a lot of bugs and critters making their home under the tarp. My general rule of thumb is if you wouldn't leave your laptop there, you shouldn't leave your kiln there.

#90662 Qotw: Which Song Plays There In The Background?

Posted by neilestrick on 11 August 2015 - 04:02 PM

I usually prefer to have the radio off while I am working, but sometimes I will put something on and crank it up. A couple of weeks ago it was Meatloaf-Bat Out of Hell. Awesome album!

#89712 Raising The Dead

Posted by neilestrick on 28 July 2015 - 03:55 PM

All Skutt kilns with the same number of sides will have the same bricks.


Any crimper will work. I use one like THIS, but not that expensive.

#89640 Tons Of Little Bumps/bubbles Showing Up After Glaze Firing

Posted by neilestrick on 27 July 2015 - 04:16 PM

Those look like bloats to me, which are bubbles in the clay, usually due to over firing. You can see that there a very small, smooth bumps that haven't come through to the surface quite yet, as well as the big bumps. Could also be a bad batch of clay, which is what I'm betting on. Use some cones to rule out the over firing possibility, though. In my experience, digital kilns tend to under fire as the thermocouple ages, not over fire, but it's definitely a possibility. However if it was truly over firing enough to cause bloating, I would expect your glaze would also show some extra fluidity, which you haven't mentioned. If you've still got the boxes that the clay came in, check to see if they're all from the same batch. Also try a couple of pots with another glaze to see if it still happens. If the kiln is not over firing, call your clay supplier and let them know what's going on. They'll want to know the batch numbers.

#89180 Kiln Fibre Board Or Brick

Posted by neilestrick on 19 July 2015 - 09:07 PM

Run away from that kiln.

#88912 Going Price Of Mugs

Posted by neilestrick on 14 July 2015 - 01:01 PM

5 years ago I was selling mugs for $30. 3 years ago I dropped the price to $26, and I now sell a lot more mugs. I can make them pretty quickly, but I do have other forms that are much more profitable. For instance, I get $36 for oil bottles, which take only about 30 seconds longer to throw, but take 1/3 as long to trim, and a little longer to glaze. All said and done they are still faster than mugs, though, and people don't blink at $36. I sell more of them than any other form. It seems like the more functional something is, and the more they will use it, the less they are willing to pay. I can get $100 for a vase, but put a spout and handle on it for a pitcher and I can only get $70.

#88840 Fair Price For Used Kiln

Posted by neilestrick on 13 July 2015 - 12:47 PM

Things are definitely different in Australia and Europe than in the US. A good kiln manufacturer should be able to get you whatever you need, though.


1, 2, or 3 phase power are all the same when it comes to firing costs. A certain number of watts are needed to heat up the kiln. Regardless of the amperage or number of wires being used, the watts will be the same, and watts (kilowatt hours) are what you pay for. So a 3 phase kiln will not cost you any less to fire than a single phase kiln. If you've got 3 phase, get a 3 phase kiln. If you've got single phase, get a single phase kiln. It's not worth the cost to try and change things.