# Hoping to get some guidance, please help.



## kleinkast (Apr 12, 2020)

Hello everyone,

First post here. I am really wondering how can you reliably melt silver down. It has been quite the adventure even locating a crucible. I ordered a melting furnace from PMC on April 3rd and it still hasn't left their warehouse. Im not into waiting for things unnecessarily, so I built the foundry from youtube Im sure everyone has seen, with the steel bucket and plaster/sand lining & lid. I put the crucible in, slowly raised the airflow increasing the temp, then i let it hang out for a bit, then i cranked up the air, reloaded the hardwood, and got the crucible red hot. It was bright red. I figure ok, we are good to go. I load 5.1 oz of shot, and watch for 5 to 10 minutes and i notice i can see the coals through the walls of the crucible. The crucible literally deteriorated from the air/heat mix hitting it (this is the best reason i could come up with. I recovered 99% of the silver. removed everything turned off air.. after 13 hours working on this yesterday, and gearing up for this over the last few weeks, including acquiring and setting up a 3d printer for sand cast molds (The 3d printer crapped out after a total of 22 hours of printing... :evil: ) Im getting pretty discouraged.. How the hell do you make a reliable way to melt silver as needed. Something solid you could base a business off of? What do professionals do? Any guidance is appreciated, Thanks.


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## butcher (Apr 12, 2020)

I like to use a small melting dish, using acetylene and oxygen.
In the past, I have melted silver in a block of hardwood with a dimple cut into it using the torch with a cold yellow smokey reducing flame to try and starve the melt of oxygen yet get provide enough oxygen to the fuel to produce enough heat to melt the silver, the wood as it made carbon and burnt makes a good reducing atmosphere for the silver...

I have melted silver in many different ways but never in a barbeque pit with a fan, heck with wood you can barely get the iron hot enough to forge much less melt and pour.


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## kleinkast (Apr 12, 2020)

Hello and thanks for your response,

How do you pour a 10 oz bar of silver, the melting dish? what about 100 oz?
I have a warehouse and I am attempting to start a serious side biz. Is it simply electric furnaces and that is what i need to locate?


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## kleinkast (Apr 12, 2020)

butcher said:


> I like to use a small melting dish, using acetylene and oxygen.
> In the past, I have melted silver in a block of hardwood with a dimple cut into it using the torch with a cold yellow smokey reducing flame to try and starve the melt of oxygen yet get provide enough oxygen to the fuel to produce enough heat to melt the silver, the wood as it made carbon and burnt makes a good reducing atmosphere for the silver...
> 
> I have melted silver in many different ways but never in a barbeque pit with a fan, heck with wood you can barely get the iron hot enough to forge much less melt and pour.



in addition to the last response, do you have any idea why the crucible side would wear through on the first run, especially when the furnace is not that hot as you say


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## butcher (Apr 12, 2020)

I never melted more than a couple of ounces of silver at once.

If I did have a reason to melt more silver than that I do have a propane furnace and graphite crucibles that will melt and hold more silver than I would feel comfortable about pouring safely.

I can always build a tilting furnace fairly easily.

Electric has its pros and cons as well as the carbon-based fuels.

If your melting and pouring that much silver at once you need some help from someone more experienced than someone like me doing this behind his barn.

There can be several reasons for wear on a crucible, from oxidizing agents forming slag in the melt from some oxidizing agent or flux.
Or maybe to where the crucible is cherry red hot almost to the melting point of the silica and an improperly designed burner in the furnace scours away at the walls with a strong blast of wet cold air, ash, and sand. Depending on what you melt at these high temperatures it can dissolve the crucibles from the gases the material chemically forms, the materials can form chemicals and gases and acids that can act like flux in the melt, taking your new crucible and changing it into slag. 
crucible used improperly, not cured and heated to remove moisture before using, used in the wrong environment, even to how you heat it like having one side very hot while the other side is cold...
Say you had a fire on the ground and your soil or the sand in your wood bark had a few pretty fluorspar rocks the calcium fluoride CaF2 take its toll on the crucible...


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## kleinkast (Apr 12, 2020)

butcher said:


> I never melted more than a couple of ounces of silver at once.
> 
> If I did have a reason to melt more silver than that I do have a propane furnace and graphite crucibles that will melt and hold more silver than I would feel comfortable about pouring safely.
> 
> ...



Ok this helps thank you. I figured the graphite was a bit stronger then that, im thinking maybe one side was hotter and the air coming in was high in humidity its been raining out here


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## butcher (Apr 12, 2020)

There are different several different types of graphite some softer or harder than others, and different types of graphite-clay crucibles, bottom line graphite is basically carbon and in a harsh environment even the best of the graphite-clay crucibles wear out.


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## goldenchild (Apr 13, 2020)

You never have to get super complex when melting PMs. The hotter a PM melting point however, the hotter temperature your equipment must be capable of achieving. Luckily silver has a relatively low melting point. Here are a couple of videos of melting silver. You simply need a vessel that can hold the amount of silver you want to melt and something to get the vessel and metal hot enough. 

This is with a simple MAPP gas torch. It takes a long time and would be much faster with an oxy/acetylene torch but it can be done.

https://www.youtube.com/watch?v=lnMkz_uXlPw

If you're going to be doing bigger melts then electric may possibly be for you. It will take longer than other methods but easier to control the temp. And as you've already discovered that's very important. 

https://www.youtube.com/watch?v=kdYbBu5MAeU


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## butcher (Apr 13, 2020)

After seeing that video it reminds me, I have melted several hundred ounces of silver many many times.
but I have never done it in a furnace or in a dish or crucible.

When I poured or make very large bars or silver anodes, I melted the silver in a cast iron pots or I have melted the silver in a mold made from a piece of angle iron with tabs welded on the end, using the rosebud on my acetylene torch. oiling and sooting the iron mold with the yellow sooty flame of the acetylene torch to prep the mold beforehand...


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## Shark (Apr 16, 2020)

This is not my video but found it very interesting. 

https://www.youtube.com/watch?v=EWA-rO8xeQ0


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## g_axelsson (Apr 28, 2020)

Shark said:


> This is not my video but found it very interesting.
> 
> https://www.youtube.com/watch?v=EWA-rO8xeQ0



Nice video, but it was cut short just before he showed off that bar. I wanted to see it!  

Did you see how rich flame he was using to heat the mold and protect the silver during cooling? The yellow flames shows they are rich in soot and is starved of oxygen. He keeps it burning until the surface had solidified, keeping it from absorbing any oxygen.

Göran


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