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Tinka
16-01-2020, 04:04 PM
Hello,
I have recently just set up everything I need to do my own at home casting... exciting!!! I bought the electric melting furnace from Cooksons and wondered if I need to heat/treat the crucible before I use it for the first time with metal? Trying to think of anything that can go wrong before I do the first cast so its a success! Many thanks in advance for any help and advise you can offer.

enigma
16-01-2020, 08:10 PM
No but you know you need to heat the crucible before adding the metal?
Also heat the kiln before adding the crucible.
Make sure you pour in a fire safe area as the metal can bounce out occasionally.
Also stir with a carbon rod and add a pinch of borax
Have fun :)

Tinka
17-01-2020, 09:06 AM
No but you know you need to heat the crucible before adding the metal?
Also heat the kiln before adding the crucible.
Make sure you pour in a fire safe area as the metal can bounce out occasionally.
Also stir with a carbon rod and add a pinch of borax
Have fun :)

Thanks so much, I had thought of heating the crucible before but not putting it into a hot kiln so thanks for that info!

enigma
17-01-2020, 09:42 AM
You're welcome.
It is to prolong the life of the crucible, also leave it out to cool in a safe place rather than leaving it to cool in the kiln for the same reason.
Be sure to check it regularly and replace before it gets too fragile too, I once had the metal come through the bottom as I had not replaced it soon enough, oops.

gaygrimes
03-04-2020, 11:55 AM
Hi, I also have a furnace from Cooksons and the instructions are very vague. I would really appreciate your advice...How long would you recommend heating the furnace for before I add the crucible? And how long should I heat the crucible before I add my metal? Thanks very much

Dennis
03-04-2020, 08:08 PM
I looked at the instructions for this furnace and apart from health and safety advice, there is not much to go on. Of course this is common for most tools of the trade.
Sarah and some other members will be able to advise from experience, but you might also glean a little by browsing on line, for instance Here: https://www.google.com/search?client=firefox-b-d&q=how+to+use+an+electric+furnace+for+jewellery
Dennis.

josef1
04-04-2020, 03:44 PM
I read somewhere that the borax attacks the graphite and this shortens the life of them

enigma
05-04-2020, 12:23 PM
I bring the kiln up to temperature before adding the crucible then bring it back up to temperature before adding the metal.
I normally work at 1100 degrees C.

gaygrimes
18-04-2020, 12:43 PM
Thank you very much, I'll try your recommendation.