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Heat Treatment Furnaces
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Author:  apollo [ Fri Aug 11, 2006 2:38 pm ]
Post subject:  Heat Treatment Furnaces

Hi everyone....

Been trying to get details of heat treatment eqpt. Can anyone help with a comparative study of the various types available (including also the price ranges) ?

I have been trying to get my hands on the Lakmini Furnace, but it seems the email I got for the manufacturers in Sri Lanka is not functioning..

In my search for good quality material, I am also getting my hands on plenty of corundum that could be enhanced and put to some use instead of being literally trashed...

:?

Author:  apollo [ Sun Aug 13, 2006 2:40 pm ]
Post subject: 

Doos, Frank ...
Sorry for the delay in my responses and also for my lack of participation these past weeks....
My DSL modem, UPS and TV all conked out during a burst of lightning and I have been on GPRS for the past few weeks :( .... I haven't also had time to even pay my landline phone bills and I have been disconnected (shame ... shame...) in the meantime.
But being a farmer, I have to complete shipment of a consignment meant for the US. A consignment just left today... and I am beginning to start breathing...

Regarding my question, thanks for the advice... But it is just that before I think of investing 30,000 USD (small deal, hah... :evil: ) plus 35% import duty plus shipping plus ......
well, I was thinking on the lines of experimenting cheap initially. 2-4 kgs per week is definitely a little much away from the comfort zone of this perpetually broke bloke here :shock:

Moreover I come from a region known to produce enough electricity to power up neighbouring states but yet does not have enough to provide itself more than 5-8 hrs per day on an average....

I'm sure Ted's running costs must be cheap, provided power is reliable... In my case, I would have to definitely set up generator backups (I hope the neighbours don't scream... well, I would definitely not hear them, would I? :P ) I was just being practical for my present stage to opt for a gas powered furnace like the Lakmini which I believe is cheap (just as I am using fuelwood, gas and solar powered options for my ginger drying.... got any solar powered furnaces? :wink: )

I went thru the site and I was pretty impressed and it would be an honour to learn from him.

"He also runs courses on how to run the cooking cycle etc but like most people involved in heat treatments the specific temperatures and lengths of time each stone should be heated for remains pretty secret."

- do u mean he doesn't tell u much during the paid training? If so, would u consider it worth the while?

Your advice is really awaited......

Author:  Frank [ Tue Aug 15, 2006 10:33 am ]
Post subject: 

Hi Apollo,

I think many of these furnaces run on gas rather than electric. If you just want to play then get a small gas test kiln (like they'd use for clay)

You won't get the temperatures needed for corundum without a big investment though.

The problem here is that the sapphires and Rubies from all the locations in the world seem to have there own requirments when it comes to heating. and though Ted showed you how to fire say gueda sapphire...what happens when you buy a load of African sapphire and the heating cycle is different.

There are some corundums around from some locations that no one yet knows how to heat treat successfully. But as Ted said in the chat...the rough isn't on sale...it's being hoarded by people who are trying to find the winning cycle for that type.

Good luck...a fascinating subject which I'd like to try too one of these days.

Frank

Author:  apollo [ Fri Aug 18, 2006 4:16 am ]
Post subject: 

Frank,
Thanx a lot for the info. I m gonna start small and let's see where it takes me....
Take care ...
:)

Author:  ROM [ Fri Aug 18, 2006 12:54 pm ]
Post subject: 

Just a suggestion, Apollo...:)

If you have only small amounts (less than a few kilos, say) of rough to heat, it might be a good idea to have the work done by experts. Some are willing to combine heating 'runs,' doing several clients' stones simultaneously in separate crucibles. I'd contact Ted to see if he'd be willing to work on that basis, or could suggest other 'cookers' he knows to be honest and reliable. Naturally, if you consider your rough high value, it would be wise to spend some time verifying the cooker's bonafides. But Ted has a fine reputation and I doubt he'd steer you wrong.

His expertise would also be of great help in determining the kind of heat treatment required. It's very complicated. The 'diesel effect' has been mentioned in reference to geuda. But in addition to diesel, Ted's book also mentions silky, waxy, milky, young, thick and Dalan geudas -- not to mention the literally hundreds of other corundum types from various world locations, most requiring different combinations of heat and atmospheres.

Good luck!

Rick Martin aka ROM

Author:  crescentgems [ Wed Mar 19, 2008 11:52 pm ]
Post subject: 

Hi Apollo,

I might be able to help you out, in getting a lukmini furnace to your hands .
Would be under US $ 5,000 ( five thousand )

Please contact me off line.

Ahmed shareek

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