Casting Slugs
Tips
This is my casting station. Backdrop,
vent hood, light, etc. The level of the casting pot shelf is about
chest high for comfortable working while standing. The shelf I
work off of is about waist high for comfort.
This is the wooden "Knocker"
I use. I can pick it up and set it down very easily and quickly.
It's just a dense pc. of hardwood.
These Guide Pins are critical. Touch
a candle to them every 8-10 slugs. When you close the mold, sort
of "Feel" them engage. Don't just click the molds together
or you'll prematurely wear the holes these 1/4" pins engage
into.
When I preheat the mold, I dip the
bottom of the aluminum blocks in the lead for about 8-10 seconds.
I also open the wing cutter and heat the wing in the lead. See
residue on wing.
I "tap-tap-tap" gently to
jar the slugs loose. Tap as if driving the wooden handles tighter.
I use the wooden "Knocker" for this.
This is the end with the two cavities.
The wing cutter gets transferred to the other end to cast that
end. It's set up to pour the outside holes for the double end
and the center hole for the single end. Works well.
This machine screw goes in the hole
where the wing cutter was (when you change ends). It does two
things. first, it keeps lead out of the threads in this hole when
you dip it for pre-heating. Second, it acts like a "leg"
to stand the mold on when pouring.
As soon as the lead "freezes",
you just push the wing around forward with the stick. If you do
this as soon as the lead freezes, you don't have to beat on things
to cut the sprues. They just shear effortlessly.
Tap-tap-tap with the handles just alittle
apart in your hand - the slugs loosen immediately. If they don't,
wait a couple of seconds longer before opening. They shrink as
they cool. If you really rush, you just have to wait anyway. They
must shrink enough to loosen.
And the drop out. I drop them onto
a heavy leather welding glove.
The single end drops just by opening
most of the time.
These are the three slugs this mold
casts. The cavities are numbered.
You see here the infinite shapes you
can cast that you could never swage. You see what I was telling
you - these only touch the bore on the outer rings. Those rings
can bite deep - give good control, and still not make the slug
too tight in the bore.
Hope all this helps.
Please ask if something isn't clear.
I know you are a good craftsman but asking always is better than
ruining something.
Most common error would be to not wax
often enough. Wax the guide locator pins and the wing (both where
it hinges and where it rubs the top of the mold block). The wax
will not hurt anything. It will "bubble" the texture
of a slug if you get too much in the cavity.
You don't have to change the handles
to turn the mold over. I've gotten so I can change the wing cutter
to the other end with the mold hot (I use a "T" handle
hex wrench in the socket head screws).
If the other end has lead and crap
on it, just rub it with the candle - the lead and stuff will float
off.