Preparing new melting dish

[yvonbug]

OK, I know you all have posted several posts on this subject. And that there is even a video on it. But, I can't watch the darn video cuz I have only dial-up.
So, I was wondering, to prepare my dish, could I use my little dental kiln? It heats up real slow and in about 2 hr.s, it finally gets red hot. It even gets the melting dishes red hot. But it's REAl slow to get there. And if that's OK, then can I sprinkle a little borax on it before I put it in? So that it warms up with the dish? Or should I wait till the dish is red hot before I put the borax on it? And, after that, should I wait for the dish to cool down before I put the gold powder in it to melt? Or should I put it in when the dish is red hot and the borax is liquid? It's like I need the A B C's. Thanks, Yvonne

 

[lazersteve]

You can add the borax to the dish after it gets above 120C.

Here is a short write up on the process using a torch, you can amend it for use with your furnace:

1) This step keeps the dish from cracking. Gently heat the melting dish to expel any water trapped in the structure of the dish. The torch should be kept on a low flame and distant from the dish at first, moving closer as it heats. The dish will make a creaking noise as it heats.

2) This step keeps the gold from sticking to the dish. With the torch on medium heat, slowly heat the dish. Add a half a tablespoon of borax to the hot dish. It will turn into a light Styrofoam. Heat this further and it will turn into clear glass like globs. Add 1/2 a tablespoon more borax an repeat until the bottom of the dish has a small puddle of the clear substance in it.

3) This step will allow the gold BB's to slide around the dish and merge easily. Use the tongs or pliers to tilt and rotate the dish while heating to spread the melted borax puddle around the entire inner surface of the dish. The inner surface of the dish should have a smooth shiny appearance form the layer of borax.

4) Add your gold powder into the center of the dish and bring up to white heat. The gold will melt into a nice button with a shiny green color to it when it is molten. The surface should not have any floating borax or film of any sort on it. If you see a film add a sprinkle of borax.

5) Let the button cool until it forms a solid surface and pluck it out of the hot borax while it is still molten. use a pair of clean stainless steel tweezers for this step.

6) Immediately quench the gold button in cold water to shatter the borax that may have stuck to it when it was removed form the dish.

7) If any borax remains on the button, boil it in 10% sulfuric acid unitl the borax crust turns cloudy and waxy like soap.

8) Remove the button from the acid with plastic tweezers and wash it in warm water to remove the waxy borax.


Steve

 

[yvonbug]

Thank-you, Steve, for sending the dishes so quickly. And thanks for the info above. It's hard to believe that in all the years that I've been doing this, I've never had to solidify my gold to sell it? The place I sold it to in Milpitas always took it in powdered form. That's in the Bay Area. So I've never really seen my gold in solid form. There's always a first time for everything. Thanks again, Yvonne ( and you'll be hearing from me soon!)

 

[creading]

Lazersteve: Hate to be dense, but are you using an oxyacetylene torch?

Prospector

 

[lazersteve]

I have one, but am not using it for the fire brick furnace setup. This is a low cost alternative that requires only bottled MAPP gas. For example, last night I melted 67 grams of gold in 7 minutes with straight MAPP gas and the firebrick furnace.

You can watch a video of this on my website:

http://www.goldrecovery.us

in the Melting Videos Section.

Steve