Transporting true hot pipes
The extruding part have to be hot for pumping to extrusion, in order to avoid wax to cool and solidify.
So I have 3 pipes : 1 carrying the melted wax, one for hot liquid – water for first tests – coming from the pump, and one for liquid returning to the hot tank.
At first, I imagined hot pipe wounded around wax pipe and the third pipe next to the others. But the heat transfer will be harzardable and.. pretty uggly !
I decided to design a more complex but beautiful carrying all pipes into the hot pipe from pump. That way, we’ve got a single pipe and thermal transfer is perfect, included smaller heat dissipation because the returning pipe is also heaten.
In one hand, the wax is meltedand pumped with precision through a pipe to be deposited with a 0,2mm nozzle.
In the other hand, the entire piping is warmed by a second circuit, with hot water if wax melts under 90°C. The water is pumped with Drinted – forget the uggly « 3D printed »… please ! – with Drinted piston pump driven by a DC motor. You’ll see my first attempts will be easy for ALL to craft, and it’s the only purpose ! (So please, keep me away from « poor guys crafted » thing… it’s all the way I like to design ! Craft from nothing is good !)
I made the head into a M10 rod, normal steel NOT Stainless steel. Stainless steel is not a good heat conductor. To avoid rusting, I have the absolute trick : the carcinogenic Phosphoric Acid from your coke 😉 (I did restore several fuel tank with that !) or phosphoric acid rated at 75% if you can buy it. A very small amount will keep any steel and iron away from rust. WaXeM will probably use glycol to allow 125°C, and this does not cause any corrosion.
The pipe is directly connected at the stop, and will feed the extrusion.
At the bottom, I use a brass nozzle taken from another hot end, with M6 connection. The nozzle is easy to drill with 0,2mm, easier that steel.
I will show you the entire process to craft it, the tricky part is how to drill in axis.
there is two keys to assemble and separate pipes : the carriage flowing and nozzle feeding and the pumps connection. so I designed the most simple parts that I can ! here you ave 3D view of carriage, pumps end box and also a simple schematic :