Simple Metal Casting with Glowforge

Wow! That is so cool. Thank you for sharing!

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I literally bought the same metal after reading the posts you linked to, but I haven’t done anything with it yet! Maybe this will push me over that edge!

I bet you could even glue a cylinder to the backing material to make a hole for a necklace cord. You’d probably want to do it opposite the pouring hole…hmmmm, something else to test!

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Awesome technique and I’ll be giving the registration bolts a try. The pewter I got is a bit higher temp so I don’t know how the acrylic would hold up, but it’s worth a try if I could get a smoother result. (Maybe I’ll try to anneal the acrylic to smooth it out. :thinking:) One suggestion though; if you’re getting bubbles or you design has an irregular shape where air could get trapped, just add small vents for the air to escape.

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We did leave the masking on in one of the runs. It was surprisingly tolerant of it on the flat side, but it got stuck on the pattern on the other. I wouldn’t do it again.

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We only put the baby powder on it. It got a bit stuck a couple times on the engrave, but nothing that couldn’t be overcome with a bit of care.

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I’ve had good luck using silicone rubber molds with bismuth alloys. Great reproduction of detail.

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I do a little pewter casting but use RTV molds. I think the melting point of pewter is a bit more than the acrylic will stand. Most pewter will melt between 340 - 450F depending on the formulation (I use Britannia Pewter). Acrylic melts at about 325F.

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NIce work! That is a tempting rabbit hole. So many neat opportunities,

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Acrylic has a pretty large coefficient of thermal expansion (meaning it grows a fair amount when it heats up), I wonder if it would noticeably affect larger pours. I think staying thin and small like a coin got you out of a lot of these problems.

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I cast pewter and would like to offer a suggestion. It looks like you have your mold on a plate while pouring the metal. After my first mold failure (decades ago), I now put my mold in a meatloaf / bread pan (metal, not glass) if it will fit, or something larger with high sides if necessary.
I only had a failure with my mold, my friend lost quite a few layers of flesh to metal escaping the mold.
This is such a great idea and I would never have thought of it since acrylic melts before pewter, but silicone…
ah, the rabbit holes I find here …
:slight_smile:

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THAT is the voice of experience
Yikes

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Great job. Thanks for sharing and inspiring.

I haven’t cast metal before, but I have cast many other things (ie, chocolate and resin). If the back of your pour is flat, what is the benefit of pouring from the top in a channel rather than just leaving the back open and pouring it flat?

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We tried that as well - it works ok, but the open side winds up with of a “pillowed” appearance instead of being flat. It’s a different effect, and looks fine if that’s what you are going for, but we were trying for something flatter.

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Very cool! Exploration knows no bounds!

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In my limited experience in casting with an open cavity, you can’t get a really smooth, flat backing. It may come out pitted and if you slightly over-fill, it will be domed. (Or outright overflow the mold.) It’s easy to sand the back and fix it, but it’s obviously more time-consuming.

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Hey there… I was at burning man and a camp did this as a craft and it was really cool. They gave me a couple of forms so I could learn from it… these sources a details are excellent, thanks

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Seems like a Make did a version of this recently, nice write up.

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That’s a great article, thanks!

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Ooh - now I want to try the coin trick but cutting that center piece using @TurboAddiction’s reeding so you get a molded coin that feels milled on the edge!

I think you’d have to use their advice for the Beskar piece of having flex lines added so the coin doesn’t stick…hmmmmmmmm

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