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Candle Making Pouring Pot...


6 posts in this topic

Posted

I wonder if anyone has used one of these to melt sprue for casting spare/extra parts???20170923_145557.thumb.jpg.6930a7cc73fb6d

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Posted

I would respectfully caution you against trying to melt sprue with heat in order to cast parts.

The processing temperature of styrene (where it will actually flow) is in the 400-500 deg. F range, MUCH higher than any conventional mold-making polymers like silicone are designed for.

Unless you have steel molds, you're probably going to have serious problems.

And steel injection-molding dies are heated to allow the molten plastic to flow into detail cavities (under extreme pressure, averaging 15.000 psi.), and then cooled to force it to solidify.

These extremely high temperatures (over twice as hot as boiling water) are also dangerous unless you have special equipment and experience.

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Posted

I would respectfully caution you against trying to melt sprue with heat in order to cast parts.

The processing temperature of styrene (where it will actually flow) is in the 400-500 deg. F range, MUCH higher than any conventional mold-making polymers like silicone are designed for.

Unless you have steel molds, you're probably going to have serious problems.

And steel injection-molding dies are heated to allow the molten plastic to flow into detail cavities (under extreme pressure, averaging 15.000 psi.), and then cooled to force it to solidify.

These extremely high temperatures (over twice as hot as boiling water) are also dangerous unless you have special equipment and experience.

Well darn... i tried to come up with options to silicone casting that i dont have yet oh well at least i learned something today.

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Posted

Well darn... i tried to come up with options to silicone casting that i dont have yet oh well at least i learned something today.

If there's a HobbyTown near you, they often stock a beginner casting kit with small quantities of the mold-making two-part silicone goo, and the casting two-part urethane goo...for not a lot of money. Just a thought, but it could get you started without having to buy expensive amounts of the materials.

You can also get it direct from Alumilite.     https://www.alumilite.com/store/p/948-Mini-Casting-Kit.aspx

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Posted

If there's a HobbyTown near you, they often stock a beginner casting kit with small quantities of the mold-making two-part silicone goo, and the casting two-part urethane goo...for not a lot of money. Just a thought, but it could get you started without having to buy expensive amounts of the materials.

You can also get it direct from Alumilite.     https://www.alumilite.com/store/p/948-Mini-Casting-Kit.aspx

HL carries the small casting kits from alumalite as well

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Posted

Even is you got the polystyrene melted, it would still be a consistency of molasses. Not something that will easily flow into a mold. That is why injection molding uses very high pressure to fill the molds for making model kits. For home-brew molding you need water-thin resin which will flow easily into a mold.

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