I could do saturday (tomorrow)! I can bring the cuttlefish and I’ll see if I have any metal I can bring.
According to the way my class has gone, if we make cuttlefish molds we ought to be able to make the molds and cast the same day. Wax is more involved and seems inevitably multiple days (or i guess one really long day may be possible)
We’re probably gonna have to figure out how we can do it ourselves since we have different equipment, but I’ll explain how my class.
Typically here’s how my class goes.
Students prepare wax at home. We use either hard wax (carving process) or soft wax (modelling/additative process. I prefer this). Hard wax is good for geometric shapes and gives you more control, soft wax is good for more organic shapes and is difficult to get clean lines and edges. We buy the hard wax from Otto Frei in oakland and I believe the soft wax is from riogrande.com. Soft wax is also called microcrystalline - they may have it in douglas sturgess. There’s also red INJECTION WAX which you can squirt into silicone molds with a special machine, but I haven’t used it yet.
in class, they add sprues, WEIGHT IT, and stick it into a metal flask, then invest it (with an investment material that is Not Plaster but is plaster-y. I know it contains fiberglass. We use a vacuum hood to get the bubbles out of the investment before it starts to set.
Then we wait 1 hour to set and stick it in a machine called a Steam Dewaxer which burns the wax out of the flask overnight.
So that’s a hard time limit - 1 hour to set the plaster and then begin the burnout, which we give overnight. We would probably have to see how long this takes us to do in our kiln, but I think we ought to expect multiple hours.
We come back two days later and the instructor has moved our flasks from the steam dewaxer into the kiln so they’re really hot. We heat up our metal by placing it on top of the kiln - (putting cold metal into a hot crucible is bad in some way that I didn’t catch). Once the metal is warm, we put it into the crucible in a centrifugal casting machine.
Here’s an image. Ours looks like this. It’s in a big metal drum which keeps any metal from escaping.
This is like a centrifuge with a crucible and spot for a flask on one side, and a counterweight on the other, with a spring that you can wind on bottom. The crucible has a little mouth on the side that pours into the flask
It’s surrounded by a tall metal wall to prevent molten metal from flying everywhere if it doesn’t go into the flask
We make sure the screws are tight and wide the centrifugal machine, then hit the metal with a compressed natural gas (CNG) + o2 torch long enough to melt the entire thing.
When it’s halfway melted, we take the flask out of the kiln and place it in the centrifuge. We finish heating the metal and let the centrifuge go. When it spins the lake of liquid metal goes up the wall of the crucible and out of the mouth of the crucible into the flask.
We wait for it to cool off slightly and remove it with tongs from the centrifuge. Let it sit a bit more then quench it in a bucket of water. Then you fish the casting out of the water and start cleaning it up with a flex-shaft machine - which is like a giant desk mounted dremel for metalworking.
So I think we ought to try to make some cuttlefish molds when we meet up and try to do some test pours to figure out how our systems works, and maybe start some prints or investments. I have some wax so if we want to try to do a burnout in the kiln maybe we could