Extruder Carriage Machined, Totally Awesome
Today I machined the carriage for the extruder and most of the components of the extruder assembly (sans thermal barrier, nozzle, and the barrel).The bottom plate (with the two angled bearings) is located to the upper plates with two pins, and the compressed springs around the screws on the bottom apply a preload on the bearings so everything runs nice and tight. I left bearing/motor shaft that pinches the filament open to the air so I can enjoy watching it feed through. Hopefully I will be finished with the construction by next week!
Categories: RepRap, Uncategorized
Nice! Do you adjust the filament tension by moving the bearing? And I’m curious which method you use to grip the filament – knurling, splining, or a toothed pulley. I’m about to try another version of that myself.
As I have stated in the RepRap forums, this work seems on the right path to Open Source Stereo-Lithography and a major step toward the RepRap dream
@Wade
Machining the parts allows me to get the spacing between the bearing and the centerline of the motor shaft within a couple thousandths of an inch. The motor shaft will have a sleeve with knurling/splining/toothing (I’m not sure which I will use yet – I will most likely test them all). Because of the ease with which I can machine different sleeves of various diameters and textures (which allows me to vary the gap) I have chosen to leave adjustment of the gap out of the design. I chose to do this because I had worries about the gap creeping larger over time, and because of the added complexity.
@Symplox
Thanks! When you say stereo lithography do you mean using photopolymers and light to cure them or are you using that as a general term for what the reprap does (additive filament extrusion) I’m very excited to see how it performs!
@swighton
I am new to the reprap etc community and am exited by it. I came upon the concept stereo-lithography at a trade show something like 12 years ago and to me it meant the general idea of building an object by deposition of material in layers conforming to parallel cross sections of a computer designed model. There must be other methods of deposition than the two you mentioned because I possess a 1/4 scale rendering of a human hand from that time frame (c.1997) that has fingerprint accuracy. The trouble is the material is both soft and brittle and the digits broke off on casual handling.
I too am looking forward to your progress, Best of Luck!
If your machine is all metal you should be able to put it inside a heated chamber to allow large prints without warping.
Do you think it will be stiff enough to mill its own parts and so be self replicating?
@nophead
I finished it today – it is extremely stiff – I would be very wary of the loads on the belts and motors if I were doing milling, if I were upgrade them somehow, perhaps to lead screws I feel confident it could do aluminum milling (very light passes of course)
@symplox there are lots of methods of depostion – they even have methods of rapid prototyping straight to metal that allows you to rapid prototype titanium parts. (fused laser sintering and electron beam deposition)
I’m glad you are enjoying my project!