Sand casting silver

[mr-dead]

Just wondering if anyone has tried sand casting silver?

You could quickly knock up some 3D printed designs and press them into the sand ready for the pour.

Just knocked up a mock 1kg silverforum bar with some added tabs on the rear to pull the mold out of the sand, made it over deep to make sure it will take 1kg of silver.

The below design would cost £36 to print out with shapeways online 3D printing service.

[PansPurse]

I love this idea. I've been contemplating a similar approach but with modelling clay rather than sand.

[mr-dead]

I have read online people use delft clay (sand with an oil additive), they then dust the imprint with talcum powder before the pour.

https://www.ebay.co.uk/sch/i.html?_from=R40&_sacat=0&_nkw=delft+clay&_sop=15

 

 

 

[BackyardBullion]

Sand casting big pieces like this is a very unique skill and pretty hard to be honest!

The results would look great on the detailed side but unlike a graphite mould the silver cools very very slowly. The end results are often very different to open cast graphite moulds. 

Also, you would have to press the delft clay every time as once it has been poured it is all burned and unusable.

But the results would certainly look pretty impressive if someone with experience and skill had a go!

[creative]

What material do you print this in on a 3D printer?

[mr-dead]

12 minutes ago, creative said:

What material do you print this in on a 3D printer?

Shapeways print in anything from plastic to castable wax, sandstone, aluminum, brass, silver, gold & platinum (precious metals are very expensive)

As you would only be using the mold to press the shape into the sand I assume you could just a plastic.

https://www.shapeways.com/materials

 

I have previously designed a gold plated brass coin for the Komodo cryptocurrency, had this one printed at shapeways -

(includes the octagonal KMD logo with a komodo climbing across it)

 

[creative]

Thanks. I was intrigued as I have a 3D printer, but I only use plastics and wood.

[Murph]

When I was being taught to sand cast we started with aluminium and simple things like door numbers or names.  The finish was surprisingly good and only needed a quick sanding.  Of course you could then start to get into a fairly complex range of additives and sand types for better results.