
~~~~~~~~~~~~~~~072v~~~~~~~~~~~~~~~

Casting

Lead, which is mortified & weighty, wants to be cast hot,
more so than tin. And when it is not hot enough, it makes lines
in the medal. ItStraw burns in it, provided it is
hot. One can make a solder so soft & runny that it can be
melted in a tin dish. It is composed of one
partlooking glass tin, one partsoft
tin, & another partlead. It runs very neatly
and is cast in leaves, but the work is very brittle & prone to
breaking. The best solder is the common one for casting well, but
is leaves certain lumpy points. Alloy lead with
tin so that the ingot that you will cast comes out even &
shiny & polished, & without any eyes or bubbles except for a
small point in the middle. And this sign will tell you that there is
enough tin, otherwise the lead dominates too much. Sand is
good for lead & tin. The good one is very thin &
fine & lean, which however sticks together between one’s
fingers. The sand wants to be reheated before putting
it to use. And once to mold with it, it wants to
be very moistened & then reheated, not all at once nor with a burst
of fire, for this corrupts & makes it shrink & crumble as well.
But if you reheat it gently, it renders itself very stiff, once well
moistened. One ought to pass it through a shirt
sleeve for the finest one, in order to first put some on
the piece to mold.

One makes a solder with quicksilverbutwhich is white, but it is brittle. Make your box
mold so that it joins well & that one does not see the daylight
between the joints.

The Germans cast their leads very thinly, rather
than very thickly, because it seems they come out better, but so that
are not too pliant, being so thin, they mix a little tin with the
said lead, which otherwise would fold up like wax.

The blackest lead, so say some, is the best & the softest
& which runs the best. You will know its goodness by rubbing it
with your finger, which will render it very black
quickly. 

The alloy good for running lead & tin is per one
lb of lead, one lb & a half of tinaultr, so that the tin exceeds more than one
part. It is solder which flows well & that is good
for casting, but it is brittle.



To make the lead flow well, one puts in a little
quicksilver.



Rub cuttlefish bone on a well smooth table to
flatten it & one against the other & cross the two bones
with pegs to mark the place.

Cuttlefish bone molds lead better than
anything else. But try it to see if it needs reheating. One ought
to mold on the back of the bones & from this side for the
marrow is more delicate there.



The bone marrow towards the tail is more delicate & does have
not as many stripes & molds more cleanly. The shell which
holds the marrow, once calcined, is good for making sand.



When you cast lead, one ought to cast it cast very
neatlyrather hot, & not at once & shake the
box mold a little & cast two or three times. However, if it
is cast too hot, it will rise up & swell. When it is very hot, it
becomes blue, let it then pass this color deva &
rest a little before casting.



Some, such as printers, mix iron filings or
pins in the lead, but in order to render it
hard. But this renders it brittle &not it breaks under
the hammer.



Take a wirebrush to clean your molds.

