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View Full Version : Source of Ceramic Wool OR Kiln Bricks



thumbsucker
1st September 2008, 11:02 PM
I am reposting this here, maybe someone here can help me find what I am looking for.

I am looking for a source of small amount Ceramic Wool (??500 mm x 500 mm??) OR Kiln Bricks (4-8) in Melbourne to aid heat retention /deflection for a small heat treating forge?

I am making some small hand tools (Crooked and Chip Knives) from O1 and need to heat treat them. I have all the heat source sorted, (4.7 Lt LPG tank, with fittings, hose, handle and nozzle).

My reading however tells me that if you are doing anything more then 3 mm thick then you need some form of heat insulation.

Can anyone point me in the right direction?

tea lady
2nd September 2008, 12:54 AM
I've got some. Got a big stack of bricks that I was one day going to turn into a kiln, but if you only need 4-8 won't put much of a dint in it. Also some ceramic fibre that a freind had given me from when they dismanteled their glass kiln. What temp does the forge go too? I don't have any "hot face" fibre that goes up to 1300°c. (The bricks can go up to that though.) The fibre I think will handle at least 900°c as that is all that a glass kiln needs.

Welcome to some. PM me.:cool:

thumbsucker
2nd September 2008, 01:08 PM
Tea Lady PM, sent.

tea lady
2nd September 2008, 01:19 PM
Tea Lady PM, sent.

:? Where has it gone?

thumbsucker
2nd September 2008, 01:24 PM
It should be in their now.

Made the claim before the deed.

Should have have said "Will send PM".

For future reference if any known' who or where a good source kiln blocks it would be most helpful.

jmk89
2nd September 2008, 01:39 PM
people who supply stuff for making pottery kilns have the ceramic bricks - eg Pottery Supplies (http://www.potterysupplies.com.au/)(Sydney and Brisbane - but I am sure there is someone similar in Melbourne)

thumbsucker
2nd September 2008, 02:20 PM
Thanks to jmk89's info I called up a bunch of pottery places, after a bit of asking around I was put unto Refractory and Ceramics, 50 Geddy Street Mulgarve (9560 4477) who sell 230 mm x 115 mm x 25 mm kiln bricks for $2 and are able to withstand temperature's up 1450 centigrade. The also stock standard bricks 230 mm x 115 mm x 50 mm for $3.70. These are 40% alumina bricks.

Here is a link to their website (http://www.refractoryandceramic.com.au/)

Two others mob's wanter $8 per brick, have to love the yellow pages.

Now I need to design a small kiln and find someone who can kindly weld a frame to house the bricks.

Master Splinter
2nd September 2008, 02:34 PM
It might be easier to use a 20 litre metal bucket and form it with home-cast refactory.

http://members.optusnet.com.au/terrybrown/ExperimentalA.html
http://www.backyardmetalcasting.com/refractories.html

Sand/cement/diatomite and paint the inside with a chalk/metho mix to reflect heat.

thumbsucker
2nd September 2008, 03:26 PM
home-cast refactory.

He actually suggested that to me, but it works out more expensive, since its almost $30 per bag of the special refactory blend. And I would need two bags most likely he says (one bag makes 1 cubic foot of insulation).

But it does seem like a simple solution all you need is a metal drum to house it in. And a domestic oven to dry it in.

BobL
2nd September 2008, 04:12 PM
Here in WA we seem to have a lot of white sand (silica) bricks which you used to be able to pick up for 50c each at a salvage yard. Pity you are not closer, I have a heap of them that my brother bought to make a pizza oven from - yet another project he's never gotten around to.

Anyway I use them all the time when heat is involved, eg to line a welding table, on and make various shaped mini-ovens out of for heat treatment purposes.

tea lady
2nd September 2008, 05:20 PM
Us potters would line a metal rubbish bin with ceramic fibre. I don't know what shape is needed for a forge type thing.

BTW, PM still lost. Maybe I'll send you one.:cool:

thumbsucker
2nd September 2008, 06:47 PM
I think I just hardened my first piece of steel.

I had a large magnet set up and I was heating the O1 tool steel as it started to glow red and scale and then I tapped the magnet with the glowing red steel and it did not stick. For a second I was awe struck :o and then a dunked it into the oil, moving it up and down.

I used a metal file and the untempered part it digs into the blade and makes a distinct GUMMY sound. When I run the file over the hardened part it skids and does not bight the metal, and the sound is very different and higher.

Absolutely amazing. :U

Now I will see if my oven gets hot enough to temper it back, this so cool.

In regards to tempering a 2 mm thick piece of O1, my readings seem to say a 200 centergrade for 1 hour will give me an Rc of 60 - 63. Is that correct?

http://www.threeplanes.net/toolsteel.html
http://www.artmetal.com/files/imported/project/TOC/proces/O1tech.html

thumbsucker
2nd September 2008, 07:48 PM
Not to highjack my own thread.

I had my knife sitting in the oven for 1 hour at 200 centigrade, it ame out of the oven golden straw yellow, like brass freshly polished. but now as it cools in the air its slowly turning silver again.

Now to see if it will take an edge.