Ok, so I'm finally going to try my hand at casting some miniatures over christmas. Does anyone have any advice over the best casting material to use?

I want to stick with metal, at least to start with, as I can reuse the many failed attempts I'm sure I'll have while I figure things out.

Is there any reason not to use some kind of pewter? I see mixed opinions on the interweb, some people saying you *need* a bit of lead in there to get into the details of the mold, others saying there's no need to bother with lead at all? There's model metal from prince august, but it's twice the price of their standard metal, but it is comparable with pewter in terms of price.

Finally, I have some Shore A22 silicon RTV that I was planning on using to make the moulds - will this be ok for casting metal, or is it for resin only?

You'll probably need high-temperature silicone for metal casting.... regular stuff may be okay for a few pours, but metal is quite heavy and easily deforms soft rubber moulds (it's also adept at escaping)

I use tiranti #4 casting alloy, it's *very* lead rich, but is quite cheap and has a low melting point, with good venting of the mould you can get really good detail, you can even do 6mm scale infantry if you're looking to cast any of your own sculpts

Pewter is fine for casting according to some others I speak to, it has a higher melting point, but if you use hi-temp rubber like RTV-101 from tiranti you're probably fine..... you can also buy cheap pewter stuff from car boot sales and melt it down which is really quite cheap....

I've had reasonable success using gedeo siligum moulds, it's too expensive for big stuff, but for small bits it's pretty quick to make a mould and is rated up to 300 celsius

I'd also recommend getting some decent mould clamps, I used to use rubber bands and dense card backing boards but if you miss with the metal, the rubber melts and springs open explosively and then you end up with molten metal all over your workspace and clothes.... for a slim mould I have been using wooden clothes pegs to hold it together, for something bigger, tiranti do special mould clamps

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Cheers Kyuss - I guess I'll save the silicon I've got for resin then. I think you've just stopped me from pouring hot metal all over my worktop!!

I used to cast with prince august stuff extensively as a kid for Napoleonics, but i now use tirantis as it is far cheaper. Prince august stuff is just packaged and aimed at a different market. Prince August bars are very easy to work with as you can snap them into chunks by hand due to the ridges on them, it's also fun to watch the lettering stay on the surface as they melt. Aside from that you're better off with bulk ingots, thought melting the longer bar of metal into a ~5cm wide pan can be tiresome.

Lead free can be fine with the right alloy, lead is generally going to be cheaper though. I also personally prefer the softness of lead as it makes conversions easier.


You will pour metal over your worktop anyway! at least i do.

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I have an old pyrex plate that I cast on top of to avoid burnmarks on the worktop and bruising of the ears from a screaming wife.... (I melt my metal on the cooker)

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pyrex, pft, I just put some paper down. That said, watch out if the paper has toner printer out on it! if you pour molten metal onto the back is transfers the toner onto the work surface … which is fun, but …

(I hold no responsibility for you burning your (or anybody else's) house down by pouring molten metals onto paper.)

fun historical background: stereotyping was a method of copying metal type forms by beating papier mache into the type, giving a papeir mache mould into which metal was then poured to make a copy (which was cool 'cos then it was all one solid plate not lots of little bits of type). You worked the papier mache, a.k.a flong, in using a 'flong brush'.

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Ok, one other thing - mould release agent - another thing I keep hearing mixed opinions on. From "you're an idiot if you don't use it" to "I never use it" - any thoughts gents?

I'm specifically thinking of when I create the mould itself, I obviously plan on using some powder in the mould when I'm casting...

I normally use homebrew mould release.... either baby oil, or vaseline mixed with white spirit.... both are effective at preventing the silicone sticking to the object you're moulding from, and I'm sure they burn off pretty quick

ooh one more thing, before you make a mould (if you haven't already) it's a good idea to scrub your models with soapy water to remove any residues from matter printing or similar.... it can make the silicone go all weird

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Nice information

I have several KG of badly cast metal miniatures (from a company I won't be using again) if you want something to melt down and use.

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Cheers E&C, I'll bear that in mind. Let me get my first efforts out of the way and I'll get back to you in the New Year - I take it's not going anywhere fast!

Nah, it's not good enough quality metal for me to want to reuse it on my own models (too high a lead content I think) but it'd be good for doing experiments with. It's similar in consistency to metal used on the earlier edition Epic models.

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Got to chime in here Ben! I'm making a 'no mans land' set of terrain soon; it's gonna have wrecked tanks and all that stuff across it: any chance that some of those badly cast mini's might be suitable as wrecks? Suitable ork and imperial proxy type vehicles is something I'd even happily throw some money at you for!

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I tried using a new company to cast 'em a few months back.
They were terrible castings so I didn't put them on sale (until now with the crowdfunder, where I'll be using my usual better quality casters).

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