Thought bubble; high flow hot ends for injection moulding
MortarArt last edited by
I just had an idea, inspired by looking at the Precious Plastic tools. Is there any reason why someone with a hot end like a Volcano couldn't machine a fixture for a small injection mould, and squeeze their filament right into it? Has anyone tried that? Is there any practical value to this idea?
Eumldeuml last edited by
From my understanding about injection molding it requires very high extrusion speeds. In commercial machines they melt the plastic in the heating/compression zone and then push it into the mold via hydraulics (or maybe also pneumatics) in fractions of a second. So depending on the size of the mold even a high powered extrusion system from a 3D printer isn't gonna cut it sadly. But I like the idea, it's quite novel!
CNCModeller last edited by
@mortarart I think it could work as log as the mould was preheated. You wouldn't get great cycle times as you'd need to cool and reheat the mould each cycle but it could work. I'd guess it'd still probably be quicker than printing the same part unless you ditto printed them with multiple print heads.
Having several moulds to cycle through would also help.
You'd definitely get stronger parts than printing, that is unless you remelted the prints in some form of sand casting process. I've used fine ground salt packed around a solid printed PLA part in the oven and it works quite well.
I guess surface finish could be much better with injection moulding subject to mould quality.
Something to add to the list for when I get back to using my mill so I can make a metal mould!
All the best
o_lampe last edited by o_lampe
The thing about injection molding that wasn't mentioned yet, is the fact, that there is often more than one injector at strategic places. So you'd also need several extruders at varying places, connected firmly with the mold.
Money-wise IMHO producing the mould(s) is the biggest part, so why go cheap with extruder-injectors?
MortarArt last edited by
@o_lampe in most circumstances producing the mould is expensive, but I feel like we're getting to the point with "reprap" type CNCs that alu moulds can be made by people with relatively cheap tools. At least that's the avenue the cooperative (Rethink Recycling) that I'm working with in Melbourne is going down.
Agreed with the above regarding mould cycle times and things like that. Definitely not an ideal solution, but more of a hack for hobbyists, who might want a really high spec plastic part say for machine construction.