Can't seem to successfully make it all the way through the button.. So frustrated....

Help Support Gold Refining Forum:

Xydoman

Active member
Joined
May 10, 2021
Messages
33
Hello again everyone. I'll just get right to it. I've been accumulating gold powder from each drop and putting it in the same beaker in hopes to melt a good sized button that had some decent weight to it. To this day, I've been successful once, and netted a button weighing half a gram... Yeah.. I kno.. The batches prior to tgat one were wrought with trouble due to ignorance. As I've learned, I became pretty good at making it all the way to the final step. The half gram button was basically a test melt from one of the drops, the axtual process escapes me, but I only use a select few that I seen to be able to handle with my level of experience and advice ftom you guys.

So here we are.. After the half gram melt I became confidant that this time was going to be different.. And it was, but I still failed. Basically, I glazed my crucible, put it into a little box I made out of refractory that captures heat quite nicely, and proceeded tk melt the powder with map gas. The torch I use is pretty gnarly.. A 15 dollar amazon number with a rose bud til designed for getting things real hot real fast. But it's hardly concentrated. It will heat a large area quite rapidly. So I'm firing it and time passes... And passes...... And paaaaassssssesssss.... I literally went through 1.5 bottles of map gas in about 2 hours, and no melt. I used borax to glaze the crucible and ddnt out any on top of the powder initially. I waited til I THOUGHT u saw it starting to melt, and sprinkled a light dusting on top. At that point.. I SWEAR i saw it start to finally melt. But nope. I ended up putting it in my foundry that will melt brass pretty quickly. It's a factory made Goliath of a machine with 4 burners. I shot a 2200 f temp at one time in the past while heat treating a plate. It stated in ttere for about 45 minutes. I removed it... The powder was still powder... There is absolutely something I did wrong.. Any ideas? One thing I can say is that it had a smell of something a kin to maybe.. Sewage? And there are pieces of slag with what appear to be glitter (gold?) contained within... Please help. I'm literally about yo givevuo on this whole hobby... Which really sucks as I've still got about 5 or 600 pounds of e scrap, I've built a vent hood, spent countless hours reading and researching and learning, decked out my wood/metal shop to sub as a lab.. I mean the fact that I'm considering just stopping out is a sign of how frustrated I truly am. As always, I'd appreciate any advice.. Straight forward.. Non sugar coated.. Here's what u did wrong dude... Type of stuff. Thanks yall
 

butcher

Moderator
Staff member
Moderator
Joined
Jan 6, 2008
Messages
9,908
Location
Pacific NW
Maybe you should consider investing in a better torch.
Map gas will work with some torches.
Acetylene and oxygen torch and proper tips for the job at hand...
With a good hot torch and a melting dish, you should not have any problems melting your gold.

Problems begin when the torch (or burner) is not hot enough (a big roaring flame does not make a torch hot), or the design or setup of your melting apparatus, or where you lose heat through conduction (normally where the torch is not hot enough to overcome the heat losses) or the dish is sitting on a heat sink sucking heat away from the dish and the gold, or the furnace insulation sucks heat as fast as a burner can make it...
 

orvi

Well-known member
Joined
Apr 13, 2021
Messages
262
propane/butane cheap classic burners (with approximate 1-2 kW power) are sufficient for melting gold, but the melting dish must be well insulated with refractory INSULATING bricks or better with mineral wool. from all sides.

most easily, cut a piece of mineral refractory wool, roll it to tubular shape and secure this shape by wrapping some iron or copper wire around it. cut the piece that covers the top of the "tube" you have just made. of course, bottom should be insulated too. than poke a hole to the bottom part of the wall for burner, and position it the way it creates vortex rotation inside the thing. dont make hole to the top unless your setup is scaled-up to higher power burner, just loosely put the covering piece to the top. flame will come out from places with imperfect "fit" :) and be careful not to overheat the burner. cheaper stuff will start to disintegrate and melt, as many parts are manufactured from plastic.
doing this, heat losses should be minimal, heat radiation should be absorbed to the walls, heating the thing quickly, but dont allowing the heat to escape easily (what i suspect to be the biggest problem here).
put the dish with gold inside and fire things up. with this setup, and 1.5 kW rated torch im able to melt gold in few minutes.
you should be able too, if it is gold :D just joking... hope it will work. dont be affraid of investing some bucks into solid quality refractory insulating wool (rated at least for 1300-1400°C). very easy working, cutting, shape forming, reusing, gas savings... and when you say you have a lot of scrap hoarded... it comes handy to do some smelting, maybe bigger foundry in the future...
and wear a respirator while working with it :)
 

Xydoman

Active member
Joined
May 10, 2021
Messages
33
propane/butane cheap classic burners (with approximate 1-2 kW power) are sufficient for melting gold, but the melting dish must be well insulated with refractory INSULATING bricks or better with mineral wool. from all sides.

most easily, cut a piece of mineral refractory wool, roll it to tubular shape and secure this shape by wrapping some iron or copper wire around it. cut the piece that covers the top of the "tube" you have just made. of course, bottom should be insulated too. than poke a hole to the bottom part of the wall for burner, and position it the way it creates vortex rotation inside the thing. dont make hole to the top unless your setup is scaled-up to higher power burner, just loosely put the covering piece to the top. flame will come out from places with imperfect "fit" :) and be careful not to overheat the burner. cheaper stuff will start to disintegrate and melt, as many parts are manufactured from plastic.
doing this, heat losses should be minimal, heat radiation should be absorbed to the walls, heating the thing quickly, but dont allowing the heat to escape easily (what i suspect to be the biggest problem here).
put the dish with gold inside and fire things up. with this setup, and 1.5 kW rated torch im able to melt gold in few minutes.
you should be able too, if it is gold :D just joking... hope it will work. dont be affraid of investing some bucks into solid quality refractory insulating wool (rated at least for 1300-1400°C). very easy working, cutting, shape forming, reusing, gas savings... and when you say you have a lot of scrap hoarded... it comes handy to do some smelting, maybe bigger foundry in the future...
and wear a respirator while working with it :)
Interesting. Well I'm a boiler tech so my setup is made from refractory, but only on 3 sides and the bottom. I've got the cracks stuffed with fiber fax.. Ceramic blanket.I put the dish tien into the recess and throw a gnarly flame on it. Works great with silver. But you're saying I need it insulated on all sides... OK. Done. So now about the "if it's gold" joke... I was actually wondering that.. I'm not very seasoned at this hobby, and tge powder I was melting definitely resembled what all the videos say it should, but the sewer smell... And the fact they it actually came out of my forge as the same powder I put in there, only had a purplish tent. In the melting dish is more of this purplish powder basically glazed onto the fish, and I see specks of actual, unmistakable gold. But this powder made up a large majority of the material. Before trying to melt it, it looked like a nice pile of cinimon.
 

Attachments

  • 16390305781473751566686291312845.jpg
    16390305781473751566686291312845.jpg
    2.2 MB · Views: 10
  • 16390306052371733995877379132251.jpg
    16390306052371733995877379132251.jpg
    1.3 MB · Views: 11
  • 16390306658986320864649696509194.jpg
    16390306658986320864649696509194.jpg
    1.6 MB · Views: 10
  • 20211204_231908.jpg
    20211204_231908.jpg
    1.7 MB · Views: 12
  • 20211204_231904.jpg
    20211204_231904.jpg
    1.5 MB · Views: 11
  • 16390312861655758425578870218281.jpg
    16390312861655758425578870218281.jpg
    1.2 MB · Views: 11

orvi

Well-known member
Joined
Apr 13, 2021
Messages
262
bricks arent the best insulation fow smaller burner. definitely, mixture was somehow clumped together, but not melted properly. from my experience, if the gold is poured (powder) to melting dish and you start to heating it up with torch, on the surface of the pile, golden luster and small clumped beads form relatively quickly (as heat isn´t dissipated so quickly to the dish). from the photo, i can see something golden-coloured, but the dish look like there is a lot of inpurities. i will try to insulate the "furnance" better, putting that refractory wool also on the bottom and hit it again, with teaspoon of borax added to flux it up. if it does not help, you will need to seek somebody with oxy/acetylene to cook it to the temperature :)
 

Jamits

New member
Joined
May 3, 2021
Messages
2
Ironically i am having the same issue with my project not melting but i added silica sand to mine with borax and i was also trying to heat it on a thick metal plate that was robbing its heat from the bottom of my graphite containers that turned cherry red hot but it still didn't melt my mixture of silica, gold and borax. I plan to get a heat gun and put a piece of k-wool on the bottom inside my home made kiln made from k-wool wrapped around a torch head off an LP tank set up. I do have a torch with oxygen but will save that for a last resort. My ideas come from Streetikps and mbmmllc on you tube. I may have the wrong sand. not sure yet
 

Jamits

New member
Joined
May 3, 2021
Messages
2
bricks arent the best insulation fow smaller burner. definitely, mixture was somehow clumped together, but not melted properly. from my experience, if the gold is poured (powder) to melting dish and you start to heating it up with torch, on the surface of the pile, golden luster and small clumped beads form relatively quickly (as heat isn´t dissipated so quickly to the dish). from the photo, i can see something golden-coloured, but the dish look like there is a lot of inpurities. i will try to insulate the "furnance" better, putting that refractory wool also on the bottom and hit it again, with teaspoon of borax added to flux it up. if it does not help, you will need to seek somebody with oxy/acetylene to cook it to the temperature :)
 

Yggdrasil

Well-known member
Joined
Oct 30, 2015
Messages
871
Location
Northern Mindanao, Philippines
According to several on the forum.
Borax are not needed to melt gold.
You need to prep the crucible with borax prior to melting that's it.
The borax on top will be an obstacle for the heat, and actually has an insulating effect shielding the gold.
Correct me if I have misunderstood this.
 

orvi

Well-known member
Joined
Apr 13, 2021
Messages
262
According to several on the forum.
Borax are not needed to melt gold.
You need to prep the crucible with borax prior to melting that's it.
The borax on top will be an obstacle for the heat, and actually has an insulating effect shielding the gold.
Correct me if I have misunderstood this.
Yes, if gold powder or silver powder is more or less pure, no borax is needed. Just to glaze silica dish.
If too much borax is added, melting dish is slowly eaten away by borax and very viscous glassy slag is formed. If you want to reuse melting dish numerous times, you shouldn´t add more and more borax with next melting.
They are relatively cheap tho. I have in use one for pure silver, one for pure gold (where no more borax is added when melting), and also two "dirty" ones, which are used to melt various crap :)
 

dannlee

Well-known member
Joined
Aug 12, 2013
Messages
96
Location
Twin Cities MN
the only way I could get a bottle-fed propane torch to button gold is place crucible on the grates of a natural gas kitchen range and pre-heat everything with medium flame from one of the burners - then feather in propane torches flame tip to try and keep the crucibles borax coating from grabbing gold micro-shot and flowing away with it or otherwise keep it from merging with the bulk of precious metals… and start slowly, the turbulence of the torch flame will scatter powders AND if the torch burner ingests the burners exhaust its instant flame-out…
 

orvi

Well-known member
Joined
Apr 13, 2021
Messages
262
the only way I could get a bottle-fed propane torch to button gold is place crucible on the grates of a natural gas kitchen range and pre-heat everything with medium flame from one of the burners - then feather in propane torches flame tip to try and keep the crucibles borax coating from grabbing gold micro-shot and flowing away with it or otherwise keep it from merging with the bulk of precious metals… and start slowly, the turbulence of the torch flame will scatter powders AND if the torch burner ingests the burners exhaust its instant flame-out…
I know the struggle, as i was pretty unsuccessful in early days with melting gold and silver. There are two main variables: ammount of heat/power and heat losses/insulation quality. Better you insulate the dish, less heating power you need. It´s nearly that simple :)
Many torches don´t premix gas/air in a good ratio, so the flame is either oxygen deprived or cooled too much by excess air. But also with these it is possible to melt it. Just sinter the gold dust with torch from the top (carefully) before putting the dish into the furnance.
My technique with one torch is to place the glazed dish with sintered gold dust inside well insulated (mineral wool) steel can and preheat the dish till red/orange hot. Then apply the flame directly to the sintered gold powder - usually it takes just minute or two for gold to melt and drive freely in the dish.
With motion of the whole "furnance" i carefully grab all the micro gold prills which are sticked to the dish, collecting them to the main gold blob. Then shut down the flame and let the gold solidify to the button. Immediately as it sets, i remove it from the dish and immerse to the cold water to dross off the slag.
With two torches, i usually heat whole dish in the "furnance" and excess heat will melt the gold, no need to directly apply the flame to it.
Picture of my sloppy setup for one torch melting. No big tech :)
IMG_20211223_133011.jpg
 
Top