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neilestrick

Member Since 04 Oct 2011
Online Last Active Today, 04:01 PM
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#64903 Do You Donate Your Work For A Worthy Cause?

Posted by neilestrick on 22 August 2014 - 11:02 AM

I only donate if it's a local cause that I have a connection to via a student or my kids, etc. I sometimes donate pots, but I often donate a class since that gets them in the door. Although I sometimes have regular students buy the class at the charity auction to get out of paying full price for that session. That bugs me a lot. The whole reason for donating was to get some new folks in the door. But that's a different rant.




#64902 My New Kiln Lid

Posted by neilestrick on 22 August 2014 - 10:43 AM

A year or two ago I posted some photos of a new experimental kiln lid for my large DaVinci kiln. Instead of being mortared together like the original lid, it used a compression frame to hold it together, similar to a Minnesota Flat Top design. That lid held up very well for a fair amount of time, but the bricks eventually started to crack. Seems they do not like being compressed along their narrow side. I had though this might be a problem from the beginning, and it eventually was. So this time I rebuilt the lid with the bricks being compressed from the large side, spreading the pressure out over a much larger surface area. I also mortared the bricks together so give it even more strength. The lid is made in two sections, held together by the compression frame. Making it in one big slab would be too large and cause a lot of cracking.

 

New-Lid.jpg

 

The best thing about this lid is that it's now 4-1/2" thick instead of the usual 3". The added insulation should help with the efficiency of the kiln quite a bit. The lid weighs 250+ pounds, more than the original lid springs could handle, so I attached an electric hoist to raise and lower it. The hoist hangs on a piece of 1-1/4" pipe, which allows the hoist to swivel as it works, and line up in the direction it's pulling.

 

So far it all seems to be working well. I did my first bisque with the lid last night, and nothing fell apart. The first cone 6 firing will be in a couple of days.




#64854 Setting Up A Kiln

Posted by neilestrick on 21 August 2014 - 01:00 PM

The air coming out the vent will be 150F or less, about like your clothes dryer. As long as it's not venting right onto a sidewalk or deck where people will be you should be fine.




#64844 Kaolin Substitutions

Posted by neilestrick on 21 August 2014 - 10:39 AM

In most glazes you won't see any effect. EPK is slightly higher in Titanium, so that can have a small effect, but for the vast majority of glazes it won't matter.

 

EPK bodies can still be translucent, but for most people that's not an issue anyway. As Biglou said, there will be a slight color difference, but in cone 6 oxidation it won't be nearly as noticeable as in reduction. If your recipes only call for 25%, the other clays in the bodies will already be affecting the color anyway. HERE is an interesting thread from Clayart in which Ron Roy discusses kaolins with some other tech guys. According to Ron, EPK is the whitest of the 4 kaolins they use at Tucker's, including grolleg. Grolleg, however, vitrifies at a lower temperature so you can get more of it into a translucent body than with EPK, which improves workability. Interesting stuff!




#64753 Another Sales Technique ... Maybe?

Posted by neilestrick on 19 August 2014 - 09:12 PM

My trick is to tell them to take it out into the sun outside my booth. It gets the pot into their hands, and the glaze (which they were already like) really pops in the sun and seals the deal.




#64725 How To Get Started With Old Stains, Etc

Posted by neilestrick on 19 August 2014 - 11:35 AM

Stains can be added to glazes to color them. i would run small batch (100g) tests with 2, 4, 6, 8, 10% stain added to a glaze, by dry weight. Stains can also be used to color slip, but higher percentages are generally needed. You can also use them to stain texture on pots or as underglazes, but they will generally need to be cut with a little frit first.

 

I would also run small batch tests of all your glazes before mixing large batches. Start making test tiles!

 

Large batches of glaze should be sieved through an 80 mesh screen. Test batches can be mixed with a stick/immersion blender.




#64717 Interesting Dilemma

Posted by neilestrick on 19 August 2014 - 08:43 AM

 

One is underfired or one is overfired, or both.  With the exception of the silica, it's close to being within limits for both temperatures. The silica is quite low in both cases, though.

 

Personally, I tend to avoid glazes that rely so heavily on one ingredient.

Why is this Neil?

 

 

If something goes wrong with that ingredient, your glaze is ruined.  When you have more ingredients in smaller amounts, an issue with one ingredient will have a smaller effect. I also find that glazes with more ingredients are easier to tweak, and offer more possibilities for substitutions should the need arise.




#64716 Kiln Amps Labeling Conflict

Posted by neilestrick on 19 August 2014 - 08:39 AM

You've got a Frankenkiln. Someone added a third ring but never changed out the serial plate to reflect the change.

 

The amperage rating on the sitter has nothing to do with the actual draw of the kiln. It's just a switch that power goes through, and it can handle up to 45 amps. The actual draw is determined by the service voltage and the resistance of the elements.

 

It's odd that a kiln of that size with 3 rings is pulling 45-50 amps. It should be around 35 amps. Someone's definitely been tinkering with it. I'd get new elements in it that are properly sized for that kiln.




#64713 Base Of Pots 'chipped Edge' After Glaze Firing - Why?

Posted by neilestrick on 19 August 2014 - 08:23 AM

You need a fresh coat of kiln wash on the shelves.




#64552 Interesting Dilemma

Posted by neilestrick on 16 August 2014 - 08:44 AM

One is underfired or one is overfired, or both.  With the exception of the silica, it's close to being within limits for both temperatures. The silica is quite low in both cases, though.

 

Personally, I tend to avoid glazes that rely so heavily on one ingredient.




#64459 Rust Red Glaze Recipe

Posted by neilestrick on 14 August 2014 - 07:05 PM

Harris Red (Revised)

Neph Sye  18.60

Gillespie Borate  9.20

Dolomite  9.20

Talc  9.20

Bone Ash  7.40

EPK  18.60

Flint  27.80

Total 100.00

 

Add:

Red Iron Oxide  11.00

 

Tends to be more red on stoneware bodies, lighter red on porcelain. Can be really bright brick red on brown stoneware like Standard 112. Looks great with the specks. I usually do a slow cool, 175F/hr to 1550F.




#64444 Pinch Pots

Posted by neilestrick on 14 August 2014 - 02:06 PM

When i do pinch pots with kids, they inevitably pinch with their index finger bent. This is a very aggressive way to pinch, and causes the clay to get too thin and lumpy. So I tell them to use 'crab hands'. Pretend you're making a crab claw motion with your hand- thumb and fingers straight out. This makes a nice soft pinch that gives more control and a smoother surface.




#64206 Reduction Kiln- Too Early?

Posted by neilestrick on 09 August 2014 - 01:59 PM

If it's a soft brick kiln, it must be under a shelter. If it's hard brick, a shelter is still recommended since you live in a cold, icy part of the country. You'll also have to consider the cost of plumbing it up with either natural gas or propane, and the cost of gas in your area.

 

The big question here is do you need a gas kiln to make the work you want to make? Or do you just need to gain more experience in glaze formulation? I used to think I needed a gas kiln to be happy, but now I realize that I have gone further with cone 6 electric than I would have had I stayed with cone 10 reduction. One is not better than the other, just different, and for me cone 6 electric is perfect for the work I want to make. So dig deep and figure out what you want to do. It's a hard thing to decide, and maybe you need to gain more experience with different firing techniques before making that decision.

 

$300 is a steal, but don't buy it just because it's cheap and different and new and exciting. Save that $300 and put it toward a wood kiln if that's what you really want to do. Or put the $300 toward spending some time learning to wood fire with some of your local potters. Michael Schael or Mark Skudlarek (both in Cambridge, WI) would probably be happy to have some help firing their wood kilns.




#64122 Please Help Me Choose Between These 3 Kilns

Posted by neilestrick on 07 August 2014 - 01:24 PM

I"m all for used kilns, if you know what you're getting into and can do repairs yourself. My first couple of kilns were used, and I got them at a great price. But if you don't know what to look for in a kiln, then you may not want to do it.

 

Say you spend $400 on a used kiln, spend $500 on a controller, but then it needs elements. There's another $300 in parts and $200 in labor if you aren't comfortable working on it yourself. If it's a 15 year old kiln then the switches and wiring are likely to be near the end of their life, so there's another $275 in parts and labor in the near future. Now you've got an $1675 kiln that's got 15 year old bricks and no warranty.

 

So if you decide to go used, find someone who knows what to look for and have them assist you. Ideally you want to check the element resistance, condition of the bricks, condition and age of the wiring and switches, and replacement parts costs. There's a lot of old Duncan kilns on the market, but elements tend to be expensive and a hassle to replace. There are other models of popular brands that have $90 elements rather than the typical $50. There are also a lot of Knight kilns out there, like the listing Schmism shows above. Those kilns are no longer made, however Euclids can make elements for most of them. I'd call Euclids first before buying a Knight.




#64047 Please Help Me Choose Between These 3 Kilns

Posted by neilestrick on 06 August 2014 - 02:00 PM

I can give you specific info about all of those kilns off forum, including maintenance costs and issues. It's a lot to go through here. Feel free to call  or email me direct.

 

Electrical code says that kilns should be on a breaker that is 25% greater than the amperage pull of the kiln. The Paragon pulls 28 amps, which means it should be on a 35 amp breaker, which doesn't exist so you go to the next one larger, 40 amps. On a 30 amp breaker it could flip the breaker if you have slightly high amperage. These are the reasons we don't put 48 amp kilns on 50 amp breakers.

 

Between the Easy Fire and the Liberty Bell, I'd go with the Easy Fire with the better controller. You'll be much happier with the full Dynatrol rather than the small controller. I can get you pricing if you don't already have a local supplier you're considering.