"Casting alloy recipes" Topic

Greetings all,

I elected to travel down the rocky and challenging path of metal casting a few months ago and thought I had it all figured out.

I had been casting 6mm Napoleonics for personal use after much struggle.

The struggle was with the casting alloy I was using.

I started with Sn92 Sb8 and even with high speed and high temperature the tiny parts on my models were not being filled even with venting and additional gates etc..

With some extermination based off research I found that adding bismuth and or some lead helped and the cavities would all be filled even with cold molds.

The celebration was short lived however when I found that the castings were far to brittle.

After more experimentation I somehow ended up with a alloy that worked well.

I have used it all up and cannot seem to replicate it.
So the question is what is the best alloy recipe for very tiny miniatures where strength and malleability are required?
I am willing to pay a consulting fee for this information if anyone knows of a caster that would be willing to share info.

Asking two ( probably stupid ) questions, have you had any better luck with commercially-sold casting metal specifically for figures, such as Prince August; and have you tried inquiring for recommendations via companies such as Alec Tiranti ( tiranti.co.uk ) ? I have found the latter helpful when I have visited their actual shop.

more important are they your designs your casting

I have tried using the prince august stuff which is how I discovered the use of bismuth to begin with.

Their stuff works wonderfully but again it is too fragile for tiny bits.

I cast at home and have had success with a half and half combination of 50/50 solder (50% tin, 50% lead) and 95/5 (95% tin and 5% antimony). It is rather expensive but if you're not casting large quantities it works well. If you don't have fine parts or undercuts you can increase the amount of 50/50 to 2/3 of the total weight, which saves on the cost.

Some of the casting suppliers list various metal mixes on their websites, and mention the relative advantages of each, so you might try checking those.

I've read that some people run several batches of metal through their molds, or stick them in an oven to warm them up a bit, before they start getting good castings, so mold temp is important to good flow.

Also, proper benting is as well. You see some small minis with lots of little thin pieces of metal attached to them, so using a pin or needle to create small, thin venting channels in critical parts to help aid flow is a good idea too. The air has to go somewhere and the liquid metal flows in.

Put up a few shots of your designs will help us figure best advice.
L

??? Really, being a bit obvious aren't we?