I was thinking about 3d printing aluminum and was wondering if you could do something like this. You have a stainless steel air tight cylinder, surrounded with some refreactory, then nichrome wire, then insulating refreactory. The first layer of refractory is to prevent an electric short between the wire and the stainless steel cylinder. Stainless steel so it will take longer to oxidize. You would fill the cylinder with aluminum, close it, turn on the heater, t would heat up the stainelss steel and aluminum and melt the aluminum. Temperature could be regulated. Air would go to a hole in the top of it, the air would be regulated by a solenoid valve and a a pressure release valve. A needle with come out of the bottom, however it would be bent into a upside down U shape and one side would poke out the bottom, this would preven the aluminum from running out when there wasn't pressure. When the solenoid is open, aluminum comes out, when the solenoid is closed the release valve is opened to get rid of any excess pressure and stop the aluminum flow. This would be put in the place of the the traditional extruder, would this work?