The idea has been discussed at length, but no-one has yet managed to come up with a working solution. Problems you may have with that design are that pla has the viscosity of honey when molten, and will probably dribble out of the end constantly, while ignoring attempts to push it. Most people have concluded it would be easier to extrude pellets into filament first, then feed it to a standard extruder, because otherwise you have to accelerate a big hopper around the place. It would be terrific if you could get this to work, but you might like to have a look on the forums/blogs to see what problems others have had first.
thanks for the quick answer.. i had at univerity a module about plastic extruders, so i know a bit about them.. more or less ,,, for injection molding there are some techniks which have a pushable extruder.. maybe this will work, or a thermal barrier inbetween the first heating and the final so that it first melts a string which gets hard a bit and then is liquidized again in the printer head... dont know it jet, but i think whith some trying this should be solable.. (sorry for the bad english, bit drunk)
EDIT: opps sorry i just recognized this should be placed in the plastic extruder forums.. @admin pleaze move..
Edited 1 time(s). Last edit at 03/27/2010 06:14PM by goaran. my projects: [www.robotik.dyyyh.de] ...
> Hi there,
> i thout about building a screw extruder..
> the advantage would be that the pellets are much
> cheaper than the string material..
> at the time im experimantig a bit..
> the aluminium tube will be heated juzst over the
> melting point to make it screwable.. this part
> will not be controlled..
> the nozzle will be heated with the default
> i dont have a reprap jet, but i will shortly
> include it in my diy cnc mill...
> for the funnel i ordered one for chemical
> purpose.. when there are any results i will share
> them with you ..
> has anybody tried this before?? do you think this
> makes sense??