The Galoot record seems to have lots of discussions about fixing the
pewter
rings holding brace handle halves together.
I was faced with such a dilemma on an old brace, retrieved from afar,
with
just such a cracked, delicate-looking pewter ring.
The various sources put the melting point _range_ (emphasis intended) of
"most" pewter alloys as about 180 to 230 C and the melting _point_
(again)
of eutectic (i.e. 6:40 lead-tin) solder at about 180 C.
I took advantage of that crucial difference between a melting range and
a
melting point by realizing that I could insinuate some molten lead-tin
solder into the softened, partially melted pewter without causing the
pewter to wilt.
Taking soldering iron and small diameter 60:40 lead-tin electronic,
rosin-
core solder in hand, I cleaned off the much used tip of the hot
soldering
iron (a two speed, 15W/30W variety, set at 30W) with flux and a file,
tinned
the cleaned iron's tip, and touched the tip to the crack in the pewter
ring.
After just a couple of minutes, I could see some small amount of effect
of
the tip on the pewter ring when ... all of a sudden ... all the solder
on
the tip of the iron sucked into a shimmering, shiny little ball on top
of
the formerly cracked pewter ring. After some filing that brought the
shape
of that little ball into melding with the ring, you can see the result
here:
http://www.georgesbasement.com/braces/Unpatented-Spoffords-Patent-brace.htm
It's the shiny spot at the right-hand side of the split in the
thin-ringed
wrist handle.
What happened is that the molten solder wetted the small amount of
melted
pewter in the cracked ring. It couldn't increase the amount of liquid in
the pewter, because that would have required more heat input from the
soldering iron, which I reflexively yanked out of the way. Now that I
think
about it, this is a practical example of a process for casting steel
that
I dreamed up a long time ago:
http://link.springer.com/article/10.1007/BF02822665
http://www.fracturae.com/index.php/MST/article/viewFile/1128/1080
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