Non-Chemical problem melting gold

[glorycloud]

hello all. I am trying to melt some gold that I have processed
and refined from gold fingers using AP. I seem to consistently
have issues when it comes to melting the gold. I don't think
what I am using is getting the gold hot enough. Here are some
pictures of the rig and what i ended up with today.






I am using Steve's melting dish but I wonder if the propylene
is able to get the temperature hot enough? Any thoughts?

 

[Barren Realms 007]

It is not getting hot enough. Does that bottle say MAPP gas on it? That might be your problem if it is not MAPP gas or if there is a draft that is keeping the material from heating up.

I might see another problem. What kind of brick is that you are heating this in? If it is not a fire brick it might be absorbing your heat rather than transfering to your dish. Also the way you have it hollowed out the flame is not able to get to the bottom of the dish where it needs to be.. Make a grove on one side that the tourch tip can fit into even with the bottom of the dish. Also do you have a top for this to keep the heat in?

 

[glorycloud]

It's a lazersteve special firebrick complete with the top.
There is a channel dug out on the bottom of the brick
that gets the heat up to the bottom of the melting dish.

 

[lazersteve]

The hard brick takes longer than the soft brick to heat up and requires the lid to remain on the furnace the entire time. I'm redesigning the furnace again to compensate for this undesired effect. The hard brick will work it just takes a little longer to get up to temperature.

You'll also need to verify that the flame is licking under the dish and exiting out the other side of the furnace. If the flame is being pushed back out of the mouth of the furnace, it can not heat the brick enough to melt the gold. If this is the case, use a 1/2" masonry drill bit to form four channels in the dimple of the furnace. These dimples should originate in the top corners of the brick at the rim of the dish and form a channel to the bottom of the dimple where the dish sits. There should be a total of four of these 'vents', one in each corner of the rim of the dish socket.

You have the right gas, the tip on those torches is slightly larger than the other types and tends to hit the inside of the entrance hole of the furnace, losing heat to the flame back tracking onto the torch nozzle. You'll need to get the flame to travel through the furnace as opposed to backing out of the front of the furnace. Increasing the size of the entrance hole to allow your torch tip in with a little spare room will also help.

If push comes to shove, just heat the gold directly from the top of the uncovered furnace and the MAPP should melt the gold.

The newly redesigned version of the hard brick will go up for sale on my site after my hand is healed.

Steve

 

[glorycloud]

Yes sir the flame is pushing back out the entry hole of the
furnace unlike the first soft model of your mini furnace.

I will try and modify the furnace with the venting channels
as you have suggested Steve. I have tried to heat it from the
top directly but it just doesn't want to seem to get the gold hot
enough to melt it though. I probably didn't allow enough time
for the hard brick to get hot either. Mr Impatient here! :lol:

This chunk is 7.5 grams and I have an another troy ounce of
clean powder ready to get melted as well. 8)

Thanks Steve. I will report back later!

 

[lazersteve]

Be sure the 'vents are riding right on the edge of the dimple that holds the dish. Do not drill holes in the solid part of the brick instead form the channels (1/2 circles) with the bit along the surface of the dimple. The purpose of this is for the flame to lick under all edges of the dish instead if kicking back out of the front.

Altering the angle of your inlet hole towards the bottom of the dish should also help. Just be sure the flame is hitting the base of the dish.

I hand make all of the furnaces so each one is slightly different. As I used my own hard brick I worked new design features into the ones I sold.

Steve

 

[glorycloud]

Thanks for the help Steve.

 

[qst42know]

Hi Steve.

Have you tried a fire inlet channel tangent to the cavity as you would in a crucible furnace. The spiral flame should give you a more even distribution of heat before it vents out the edges and the flame is less likely to back flush through the inlet.

Chris

 

[lazersteve]

Hi Steve.

Have you tried a fire inlet channel tangent to the cavity as you would in a crucible furnace. The spiral flame should give you a more even distribution of heat before it vents out the edges and the flame is less likely to back flush through the inlet.

Chris

Not a bad idea Chris. I'll give it a go.

In the mean time I'm trying my hand at casting a few different designs of mini's to see which works best and is the easiest to make.

Glory,

Your gold is very beautiful!

Did the larger blobs not get fully melted or did you pour the molten gold out on a surface to get the 'squashed' effect? The gold is ready in the furnace when it all pulls away from the dish around the perimeter of the button.

The molten gold should flow freely around the dish when pushed around with the flame of the torch.

Steve

 

[glorycloud]

Steve,

I did pour the gold out of the dish into water and it did move
freely around the dish as it was pushed by the flame. I used
both the open top method and the mini furnace closed up as well.

I can't seem to get the pretty gold buttons that the you guys seem
to be able to create. 8)

Thanks again for the help!

G_C

 

[qst42know]

If you want them round allow the gold to solidify in the dish and pull it out just before the borax hardens. It's a timing thing.

 

[glorycloud]

I will give that a whirl next go round. Thanks!

 

[stihl88]

I use the same Gas bottle you do and the same torch head but i upgraded the torch head and it burns nearly twice as hot as the standard head now.

 

[glorycloud]

That's great. Care to share what you purchased there amigo? 8)

 

[donnybrook]

Problem melting gold. Glorycloud. What Barren says is correct. Gold can be a fraction of melting point and it will sit there or just lump together. Had it happen to me. You are losing temperature for some reason draft etc. I use a cylindrical cooper made from an LPG bottle (build with care). Get lots of firings out of it but the dish you are using is more economical.

Donnybrook