Wow nice projects you found there, I didn't knew that more projects have been hiding in the chaos of open source development. I did some long and boring research work, but these projects (which are very vuluable) I didnt find so far.. thanks for the links! Ill incorparate them in my project page so people will find thair way in the future more easilyby Ward Hupperets - General
@gspot you totaly got the picture of the problems that will be encountered when using this concept. the question is to what extend the venting problems take place after first extrusion, it might be a minor problem or a mayor problem, it will be something that will clear out when first tests are performed. Venting of the melt in the buffer chamber might be achieved beceause you release pressureby Ward Hupperets - General
@gsport allright guys... I realise it is realy hard to get a good picture of the project development so far. Ill explain it short: first stage: - Polymer granule is fed into a cold hopper at the top in atmosfere conditions. (continiously fed by a hose or something else) - The screw in the barrel with the tip pointed upwords and the hex head at the bottom rotates, and so transports the granuleby Ward Hupperets - General
@bobc we allready have the filabot project for that... plus, being able to pressurize the polymer melt in a different way than just pushing on the melt with cold filament, creates new possibilities, like using higher molecule weight materials (the higher the better for FDM) and faster extrusion thus faster printing speed.by Ward Hupperets - General
try a programm called spaceclaim... it's easy to understand, but hard to get to I guess. I've had contact with the general manager of the dutch distributor, that how I came with the programm... You can transform .stl files very easily to solid bodies... (tried it myself they call it reversed engineering) and it can read every cad data... Im still learning to use the programm but still you can tby Ward Hupperets - General
@ttsalo your proposal is good, as you might have seen in the last prototype drawing I made on my project page, it only exists of a screw housing and a screw. with a little hole of 1 mm diameter. exactly for the reasons you talked about. maybe with the goal of a two stage extruder I want to achieve to much at the same time. Ill be producing the last prototype design next tuesday, but I might mby Ward Hupperets - General
@gsport do you think the sealing problem could be solved by introducing a counter twisted helix groove inside the blank side of the screw, below the hole? In that way, material that passes the hole will be transported upwords again. I chose for reversed extrusion direction beceause a thermal barrier at feeder and hopper end will be easier to achieve, when using an overhead extruder this will beby Ward Hupperets - General
VDX Wrote: ------------------------------------------------------- > ... as you apply heat, pressure and tumbling to > the molten plastic, the sealing is a really > difficult thing. > > You need extreme high precision for the > auger-shaft and the throughput - your 0.02mm is > only possible with bearings on both ends or a > longer shaft and aditional fixture under the &gby Ward Hupperets - General
@gsport I guess the problem with drive above auger, is that you need a structural support, which ads to the total weight of the printer head (since the forces on the auger are pointed upwords) "reversed" extrusion direction, solves makes the construction way more simple, but the problem of sealing pops up. CAN WE TACKLE THE PROBLEM OF SEALING??? ANYONE?by Ward Hupperets - General
@crispy At first, I will only focus on the use of vergin materials, so I dont have trouble of degraded plastic etc like you say. I'm aware of these problems. The goal of recycling material is not a realistic achievable goal beceause of the problems your talking about. Initially this was the goal of the project, but I left this goal in the second week, since it requires a properly working granulby Ward Hupperets - General
In the engineering of injection molding, a very narrow channel is good enough as a fluid seal. since polymer melt is a high viscose fluid it will not flow trough these narrow channels, beceause to much pressure would be required. between the two mold halves these channels are manufactured to release the air in the molt cavity when fluid is forced in. this works good if properly designed. (0.02 mby Ward Hupperets - General
Hello community! There are always some projects going on with the devolopment of a granule extruder, beceasue of chaos properties of open source development, I will post this to notify you about the most recent (first quarter 2012) projects regarding granule extruders, including mine I would like to notify you about my project, which is partially bases on research such as this forum topic and oby Ward Hupperets - General
Hello community! There are always some projects going on with the devolopment of a granule extruder, beceasue of chaos properties of open source development, I will post this to notify you about the most recent (first quarter 2012) projects regarding granule extruders, including mine I would like to notify you about my project, which is partially bases on research such as this forum topic and oby Ward Hupperets - Developers
Hello community! There are always some projects going on with the devolopment of a granule extruder, beceasue of chaos properties of open source development, I will post this to notify you about the most recent (first quarter 2012) projects regarding granule extruders, including mine I would like to notify you about my project, which is partially bases on research such as this forum topic and oby Ward Hupperets - Developers
Hello community! There are always some projects going on with the devolopment of a granule extruder, beceasue of chaos properties of open source development, I will post this to notify you about the most recent (first quarter 2012) projects regarding granule extruders, including mine I would like to notify you about my project, which is partially bases on research such as this forum topic and oby Ward Hupperets - Mechanics
good question: not yet sealed, First test was just a try out. when I will perform the second (cold) test with wallpaper paste I will use an O-ring around the blank shaft of the screw. (I will grind a little round grove in the shaft so it will be axialy fixed) in the new prototype I will need to have a proper seal, do you have a proposal?by Ward Hupperets - General
Hello community! There are always some projects going on with the devolopment of a granule extruder, beceasue of chaos properties of open source development, I will post this to notify you about the most recent (first quarter 2012) projects regarding granule extruders, including mine I would like to notify you about my project, which is partially bases on research such as this forum topic and oby Ward Hupperets - Kartik M. Gada Humanitarian Innovation Prize
Hello Community! I can use your quality feedback on the following project!!! PROJECT PAGE check my project about the devopment of a granule extruder... ultimately to be able to rint with shredded plastic waste chips. As you might have noticed their are several different projects focussed on the development of such an extruder, I'm currently in the stage that the project will be lifted to a morby Ward Hupperets - General