[kravocado]

Hello all,
I am working on a project that will require me to melt some tin. As far as I could tell by the MSDS this should be relatively safe, but I would like to get an experienced chemist's opinion before starting this project. Is melting tin safe?
Thanks,
-Kravocado

[Arkcon]

Well, you should always work with good ventilation, for your own safety against whatever tin gets volatilized, and any fumes from your heat source. It really does also depend on your scale.  How much tin?

[Enthalpy]

In electronics we melt tin-lead and now tin-copper wire all the day right under our nose and don't get sick from it. Only the added rosin is uncomfortable but blowing on it suffices.

I mean: heat until it melts, not more.

[kravocado]

About 500g-1kg at a time, but it only be melted long enough to be reshaped, and very gradually, so the whole amount wouldn't be formed for several hours.

[Enthalpy]

In this attempt, burns and fire must be the biggest risk.

Melting tin is pretty common. For instance decorative objects are made of it. You could check what kind of precautions craftsmen and industries take.

Does your tin contain alloying elements like antimony?

[kravocado]

In this attempt, burns and fire must be the biggest risk.

Melting tin is pretty common. For instance decorative objects are made of it. You could check what kind of precautions craftsmen and industries take.

Does your tin contain alloying elements like antimony?

I plan to try mixing in various plastics, in order to change the qualities of the final product. I was thinking that I would try PolyLactic Acid first.

[Borek]

Plastic and molten metal? I don't see them mixing, just like water doesn't mix with oil.

Fuming, yes, and the fumes can be much more nasty than the tin vapor itself.

[Enthalpy]

Not mix, and worse, the plastic will decompose at this temperature.
Fumes from most plastics are bad.

In short: it won't work and is unhealthy. Don't do it.

[Intanjir]

I'm not sure whether the thermal issues make this is all that implausible. PLA is commonly extruded for 3d-printing at a setting of 210-230 °C. Tin melts at 232 °C.

I've noticed that at the start of a print I detect a burning scent that quickly ends once the plastic starts streaming from the nozzle.
Wikipedia informs that above 200 °C PLA cannot be polymerized as forming lactide monomer becomes favored.
So I think that the PLA is likely not stable at the temperatures used for printing but that this doesn't cause any immediate catastrophic problems.


1 kg is much too much. This has Pyrex test tube and fume hood written all over it, although the test tubes might not be recoverable afterwards.

I wouldn't bother though.
The high viscosity of molten plastic, the large difference in density, and the mutual immiscibility of the two materials will make any kind of intimate blending of two extremely difficult even if they are sufficiently thermally compatible. You would need to design a very fancy custom built apparatus to get any kind of fine emulsification.