Non-Chemical Smelting problem

[nickton]

Yes indeed. I meant a furnace of course. I had made a couple of round ones but they didn't work as well, though that was before I bought the torch tip and high pressure valve. I had to make this one square because I used bricks and was limited to the small ones I bought. This furnace is admittedly improvised, but it seems to work well. For the vent I just open the door a bit and can adjust the air flow. Also the perforated stainless steel I managed to roll into a tube permits air passage and I can push the tip in or out to adjust the flow. Surprisingly it seems to work quite well and is so small it heats up quick. Primitive yes, but effective. Maybe in a few months I will change my tune but I guess this is the level I'm at now and it's working for me. :mrgreen:

 

[nickton]

By the way thanks for all the help from this forum. I don't mind being corrected at all, so don' t worry about that. It's taken me a while to absorb a lot of this information in a way that makes sense to my layman's mind.
I have never taken a chemistry class in my life and am trained as a carpenter, so I apologize for sounding amateurish, which I most definitely am.

 

[Geo]

Lazersteve sold a small furnace made from two insulating firebricks. There was a cavity made by a wood router that a melting dish set on. It was cut with a chamber on the bottom and a hole to place a torch tip pointing inside. There was grooves around the edge of the dish so that the dish was sitting on four points. That way the flames could pass the dish into the top chamber. A second brick with a chamber cut out with a vent hole to vent the spent gasses was placed on top of the first brick.

 

[Geo]

I don't think he sells them any more.

 

[Geo]

Also, to clarify, you are not having smelting issues. You are having melting issues. There is a difference. Smelting is a process where you reduce metal salts in a furnace with reducing agents at high heats. You can also liquefy rock that has tiny particles of precious metals so that a collector and flux can be added to extract the metals. Melting is simply melting metal that is already in metallic form and is relatively pure (free of rock or silica).

 

[TreySeaJax]

Kaowool is cheap and easy to work with

 

[Chirou]

Hello it's me agai i got question about melting gold o got LPG 11kg gas with torch temperature gets up to 1800 degrees and the problem is i got one batch of gold with borax which was previously melted but temperature was too low to smelt gold will there be any problem with remelting it or should i add something or dunno crush it or something.

 

[FrugalRefiner]

i got one batch of gold with borax which was previously melted but temperature was too low to smelt gold will there be any problem with remelting it or should i add something or dunno crush it or something.

I'm a little confused.

You say you have "gold with borax which was previously melted". What melted? Did the gold melt, or was it just the borax that melted?

Then you say the "temperature was too low to smelt gold". You weren't trying to smelt the gold, just to melt it. So, I'm guessing only the borax melted, not the gold?

Once we know what melted, the next question is do you have a lump of this material by itself, or is it stuck in some kind of melting dish or crucible?

Sorry to answer your question with questions, but we'll need some answers to give you good advice. In theory, you should be able to simply remelt it, but if you answer the questions, you may get a better answer.

Dave

 

[Shark]

This is a good example to the saying "a picture is worth a thousand words".

 

[Chirou]

Well i don't have a oportunity to take picture now, but i uset butane torch and it only metled borax and all gold powder inside only came up into few lets call it veins and refused to actually melt. And i was wondering if i got batch like that will i have any troubles melting it or just normally attempt to melt it.

 

[FrugalRefiner]

i uset butane torch

This may be a language/regional issue. Some people use the terms butane and propane interchangeably. You'll probably struggle with butane. Propane or LPG can do the job, but you still need to insulate the melting dish well. MAPP is preferred by many. A propane/oxy or acetylene/oxy system is the fastest generally used. All benefit by insulating the melting dish so you can apply heat faster than it can escape.

it only metled borax and all gold powder inside only came up into few lets call it veins and refused to actually melt.

If your gold is coming up into the borax the way you described, you're probably using too much borax. You should only need a light glaze on the surface of your melting dish.

And i was wondering if i got batch like that will i have any troubles melting it or just normally attempt to melt it.

Do you have a different torch or set up now? If you had trouble melting it the last time, unless you change something, you'll probably have problems again.

You can either try to melt it again as it is, or you can dissolve the borax and start over with the unmelted gold.

Dave

 

[Shark]

One of the things I have learned in trying to reach high purity is to pay close attention to how fast the gold starts to melt. I noticed that my best buttons start to melt very quick and evenly. When they seem to take a bit long (more like just a few seconds), when they take a bit long or start to melt more in a localized spot I know and have always been proven right in the lack of quality. Most impure gold takes more heat to melt.

One thing that is mentioned in the brick furnace post about Lasersteves is that it took about 15 minutes for it to do a good melt. I would think that is a sign that the gas is barely able to reach high enough temperature. Mapp gas will get notably hotter than propane or butane. I most often use oxygen and propane, but I have oxygen and acetylene as well.

 

[grainsofgold]

gold powder you started with -

Was it pure gold from a refining process ?

If so, then why would you need to use a lot of borax to melt it?

Trying to understand what you started with and what you were trying to do ?

 

[Chirou]

Yea i changed my set up from butane torch to LPG 11kg torch and i'm building small insulation "wannabe furnace" to keep temperature.

Well in first try i got more powder after burning filters than i expected and it was kinda a lot for my little cruicible. And i didn't graze the dish as i should have done before atempting to melt gold.
I don't really think that my first try was pure gold i'm sure i overdid and got some copper with it.
Now i'm waiting for new batch to finish.