Sciencemadness Discussion Board

Kiln progress

12AX7 - 28-8-2005 at 19:51

http://webpages.charter.net/dawill/tmoranwms/Cer_GasKiln.htm...

Gettin' there.. have to cut holes for the burners, maybe add another layer of kaowool (tests show one layer is going to get paint peeling!), not to mention build the ceiling...

Tim

IrC - 29-8-2005 at 08:50

Are you also using bricks or just the kaowool? If bricks, do you have a good source you can post (I would also like a good place to buy the kaowool too)?

12AX7 - 29-8-2005 at 09:03

No bricks, just the castable. I was thinking of lining it with mullite or cordierite tiles, though.

Fleaker has lots of kaowool so I hear.

Tim

IrC - 29-8-2005 at 09:38

Do you have a source for the castable stuff you can post? Myself, kilns are a new subject and I am learning as I go along, I bought a factory made one (an Olympic) and never thought I would have to learn how to work on them or where to find materials. I was bummed out that such a new kiln with so few hours would be a pile of bricks on my table so soon. I had to actually take it that far apart to remove the heating element, and will have to replace a new element in reverse order. I ask about the castable source as two of my bricks are broken in half (I had noticed two bricks where light and heat came through since I bought it, they must have cracked in shipping). Anyway, I was trying to decide if I needed to buy these two bricks from Olympic or if this castable stuff you mention could be used to repair the broken ones I have (as well as where do you buy that stuff)?

12AX7 - 29-8-2005 at 11:09

Refractory is best bought locally. Most people do not appreciate paying as much for shipping as for the product itself. :P Look in the phone book.

Tim

IrC - 29-8-2005 at 22:07

Do you know where I can find ITC-100, I tried every single link google comes up with to no avail, searched ebay and various other places. Who carries this stuff?

my kiln

((Blasta)) - 30-8-2005 at 00:23

I have a gas powered --heavily insulated kaowool kiln made from a surplus oil drum... works well. I can easily make Rakuware and other forms of pottery. I've even melted copper and poured metal into molds

I fire the kiln with Propane and use an electric high velocity fan to increase air flow and heat output. I'm positive that the kiln could reach 1300 C without issues.... and I'm only pushing 40% power into the fan. I could see temperatures going up another 400 C if I blasted the fan at 100%....that might cause a meltdown.

On another note my friend has a heavy kiln that runs propane...and he even has a spare port for adding a very limited amount of Oxygen to the mix. It is a crazy unit.... 2000 C I'm sure of it.

uber luminal - 30-8-2005 at 06:41

Blasta... a "friend" with a 2000C gas kiln? I really doubt it. unless what you mean by kiln, is a very small box.

Lets just say, you could run a kiln on the optimal ratio of oxy/acet, but in order for a flame to keep working, you need to expel product gasses, and keep the pressure in the main chamber lower than the outside. Even with oxy/acet, it would be very difficult to heat an entire large area. maybe if you had 50 torch heads or something rediculus like that.

In the metals industry we use electricity in 5 or so various processes that work a lot better than gas. Even with electric (which allows you to completely close off the kiln to trap the heat more effectivly) its hard to reach past 1800C with an enclosure like a kiln. Induction and bombardment is how anything above 1800C gets done.

Oxydro - 30-8-2005 at 07:58

Irc: Budget Casting Supply carries ITC-100 (here) but it's not cheap.

[Edited on 30-8-2005 by Oxydro]

((Blasta)) - 30-8-2005 at 08:32

The kiln that runs what i "think" is able to run 2000C is a small 1" thick high temperature steel box. The unit itself is 2' wide by 4' tall. Their are 2 openings that are connected to a high velocity air fan, 1 major propane input and 1 Oxy input. The inside of the kiln is composed of Kao wool and fire brick. I've seen steel being poured. Its quite impressive! Honestly I'm not sure of the temperature inside... but doesn't stainless steel melt down at 1700 C ?

[Edited on 30-8-2005 by ((Blasta))]

12AX7 - 30-8-2005 at 08:34

See, farenheit rocks your socks. You can pick some bigassed number like 3,000, and it's within reason. 2000°C is a nice round and whole number, but damned if you're getting there without some serious hardware! :D

(Or cones... about 50C per cone, as much precision as you'll ever need, one step at a time... no messy "oh firing to 1,236C" crap! ;) )

Tim

((Blasta)) - 30-8-2005 at 08:37

....just called Mike... he told me that 1810.5 C has been reached at maximum with the kiln. Close to 2000C but not close enough ;)

right you are guys, me wrong.

IrC - 30-8-2005 at 11:56

Thanks oxy, I also found a source at Tuckers for itc 100 and 200 but shit, ~$100 a quart or $335 a gallon!

Fleaker - 30-8-2005 at 12:54

Don't worry IrC, I've got a better source for you. How's $26 for a pint of it (probably as much as you'll need)?

You want the ITC-100 stuff btw. If you need kaowool, drop me a line, I've got the 2300F-2600F material (for back up insulation) and if you must, I can get a special type good to 3000F.

Here's the contact info, this guy gets it cheap and sells it cheap:

Jay Hayes
C. J. Products Inc.
(304) 269-6111
E-mail: xmas4lites@earthlink.net
He will e-mail you a full list of what he has available and prices.


BTW, uberluminal and ((Blasta)) I've melted stainless before, and that goes around 1650C/2900F in my gas furnace but my refractory is rated to 1800C max service temp.

IrC - 30-8-2005 at 14:58

Thanks Fleaker, I was getting depressed looking at prices on the net.

Ceramics and pottery

Lambda - 30-8-2005 at 15:33

IrC, have you made any inquiries from art (ceramics and pottery) shops yet ?. We have many of them in Holland. I know of one pottery shop, that has a few ovens of about 3*3*3 meters. They give pottery courses there. I will make inquiries for you on thursday, ok. I will ask them for Internet sources relating to isolation (brick material), cement (castable) and heating elements.

Clay Art Web Guide:
http://www.vickihardin.com/links/ceramicsupplier.html

Yixing Feifan Ceramics Products Co., Ltd.:
http://ffceramics.en.alibaba.com/group/50045130/Ceramic_Oven...

IrC - 30-8-2005 at 18:03

Thanks Lambda, so far I have with everyones help found sources for everything except the heating elements I wish to use. I can buy the factory replacements but this kiln was nearly new so I figure why the hell bother with that? Burned out once, will do so again! I was reading all the kiln info in other threads here after doing searches, and axehandle has the most information on SCM. After doing some axe-study, I want to find the .7 mm Kanthal-D wire he uses. He did post one source but I need to find it in the US. Part of my problem has been not being sure what to look for, and so it was helpful to read a lot of his stuff, and on his site, just to learn how to go about doing things and what to use.

The cheap way out is to just pay the $25 for a new element, and buy the 3 cracked preformed bricks also from Olympic. Then I thought I should also buy a couple pints of the ITC 100 and well coat all bricks before I reassemble the kiln. But I keep coming back to the fact that as near as I can tell these kilns are designed to run up to cone 10 in a firing run and shut off, whereas I run up to cone 10 and let it go for 9 hours at a stretch glowing like the sun. So finding this better wire and really coating the bricks would allow me to maybe have it withstand constant operation at 2,350 F. I think. I also found sources of 50 pound bags of castable, I thought about making the walls thicker as well. A learning experience. I did have one thought. I remember the quartz halogen bulbs for copy machines, about a quarter inch diameter and 10 inches long.

If I could locate dead ones and break the ceramic ends off, pulling out the old burned filaments, maybe I could encase straight runs of the .7 mm Kanthal-D wire with refractory sealing the joints and bends together, so as to completely isolate the wire from the fumes in the kiln. Just a mad science thought.

As to looking around, it sucks as I am too far from anyone selling such things, as 12AX7 mentioned, the shipping the shipping. I found 20 dollar bags but the UPS is $35 for the 50 pound bag. No choice here though, nobody within 200 miles of me sells such things. I am getting a good education in all this and that can only be good.

I found this kanthal PDF online, and if it vanishes I also added it to my upload/books directory on axehandles:

http://www.lg-studios.com/images/Handbok.pdf



[Edited on 31-8-2005 by IrC]

hinz - 1-10-2005 at 05:49

I have some questions about my own furnace, which I’m building at the moment.
Because there are so much topics about furnaces, I don’t want to open a new one and post it just here.
My furnace ( the basic construction) is more or less finished, the heated chamber is 42x12x12 cm. The chamber walls are 3cm heat resistant stone (schamott-stone). The isolation around it is 10 cm glass wool. The heating wire is 1mm Kanthal D I think (It was only labelled as Kanthal wire but they wrote close to it that it could be used up to 1320°C) I bought 50 m of it, and wound a coil ( used 40 m) with 10mm outside diameter. With the Ohm's law I get 2.6KW @ 220V.

-Do I need an active heat control, when I run the furnace or will the resistance increase so that the furnace regulate itself at 1300°C. If yes how can I realise the heat controller, maybe with an AVR microchip a thermo-element and some power relais since there are no 2.6KW Variac’s ( but I don’t know much about AVR programming )

-I need a carrier for the heating coil, since it starts softening at appr.1100°C, will ordinary ceramic work, at the beginning I thought about quarz glass tubings but they will start softening at 1200°C and long use of the furnace would end up in deformed heating coil carriers.

IrC - 1-10-2005 at 09:11

An infinity switch would regulate temperature, and Olympic at http://www.kilns-kilns.com/ has them for fairly low prices. Just find the kiln in the class closest to what you built and look up the part number and price.

protecting kiln elements

densest - 1-10-2005 at 17:57

The same people who make ITC-100 also make metal protecting paste called ITC-213. It's supposed to be applied to any metal in the hot zone. The review I read said that it preserved Kanthal elements for a year or more. Impressive if it works.

IrC - 2-10-2005 at 07:57

Fleaker, thanks for the info on Jay. I have made 2 orders with him and seldom do I find people as good to do business with.

IrC - 4-10-2005 at 22:13

The ITC-213 is also a great idea. I did some research on it and decided I need to get some of this, Jay also carries the 213 at half the price of every other supplier online that I could locate. I also found that kiln makers like Olympic do not normally use either but if you pay out the ass they will pretreat a kiln for you as it is being built. They do not mention it on the site that I could see but know about it when you call and mention it. For 900 percent less you can just order from Jay and do it yourself like I did. Olympic also pissed me off when they made a comment about not "telling me how to build a kiln I can buy one from them" when my questions were very simple, I was asking for what size and cost bricks they carry as I was designing my own. This was rather depressing as all I wanted was to calculate the number and cost of the bricks I would need.

12AX7 is right it would be so much better if someone near me carried these so I could just go look and measure for myself, not to mention saving the shipping. It sucks when a company would rather make a hassle over you doing it yourself than just be helpful and sell you the materials needed. Good did come out of all this, I have learned much more than I even thought I would need to know and Fleakers information on Jay led me to a great supplier of anything a mad scientist needs for kiln construction, improvement, or repair.