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Will regular leaded(or non-leaded) solder stick to actual tin or tin foil? Does the tin have a low enough melting point that it'd melt along with the solder? Has anyone actually tried soldering copper to tin using regular solder?

(I tried googling, but everything I found seemed to be about tinning a soldering iron)

Edit: Note I was talking about the actual metal Tin. I realize that most "tin foil" is actually aluminum and you've given me some useful information about aluminum but what about actual tin?

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    \$\begingroup\$ Common "Tin Foil" is actually aluminium foil. Also, no. Solder will not stick to aluminium. \$\endgroup\$ – Connor Wolf Sep 2 '10 at 8:28
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    \$\begingroup\$ You may be better off just taping a wire onto the foil \$\endgroup\$ – Toby Jaffey Sep 2 '10 at 10:26
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    \$\begingroup\$ Solder will stick to aluminum, if the oxide coating is removed. One way is to scrape the surface under a small pool of oil, and tin the aluminum under the oil. \$\endgroup\$ – Leon Heller Dec 4 '10 at 0:08
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    \$\begingroup\$ @Leon - Not easy, scraping 0.02mm aluminium foil... :-( \$\endgroup\$ – stevenvh Jul 21 '11 at 13:00
  • \$\begingroup\$ Dilute hydrochloric acid can be used to remove the oxidation layer. Just be sure to solder to it very soon afterwards. \$\endgroup\$ – Nick T Aug 17 '17 at 14:46
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Regular solder is a mixture of lead and tin, so chances are that, yeah it would stick to actual tin.

Be aware that most of what is today called 'tin foil' is really made of aluminum. You would have to work at it to find tin foil made of real tin.

Aluminum is notoriously difficult to solder to, almost but not quite impossible, in fact. Basically you have to exclude oxygen from the surface you intend to join, which is easier said than done.

As regards actual tin, you should be able to solder to that, since most common electronics solder incorporates tin as part of the alloy. Pure tin will melt at a higher temperature than solder, since the alloy has a lower melting point than any of the individual components, so the joint should actually be a solder joint and not a weld.

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The melting point of tin is 232°C, so it will indeed melt at normal soldering temperatures, like you suggest. However, soldering isn't about melting two metals together. For instance take copper. Melting temperature is 1084°C, so your soldering iron will never melt the copper. Yet you're able to solder it, because atoms of your solder migrate in the copper's top layer. That happens even when the copper doesn't melt.
So solderability isn't determined by melting temperature, but by whether the metallic structure will allow the solder to penetrate it. Aluminium Oxide (what we actually see when we talk about aluminium) is absolutely impregnable for molten solder.

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Yes, pure tin is wettable with solder. However, I believe there are some alloys that make it particularly difficult.

If you just try to solder something directly to a large tin part (e.g. casting), it will be extraordinarily difficult because of its large thermal mass. You would have to use a torch or high-power soldering iron to accomplish that.

Alternatively, if you're attaching a wire to a huge part, using a stud (or bolt), nut, and ring-terminal would be more convenient in many cases.

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Yes. Tin (Sn) is a major component of tin based solders. If you can avoid the collapse of molten metal into the ball it is very possible to make a joint.

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