Kossel Build update: First print!
Posted By sphetz On Wednesday, 16 September 2015
The 1 meter tall Kossel printed it's first print, a step calibration cube. The bed is 10 inch mirror glass from Joanns. I followed my original plan for the most part except for two things. One, I am using a Smoothieboard 5x instead of a 4x , which doesn't change anything because I am not using the extra stepper driver for anything. Two, I have yet to add a third triangle on the bottom for more rigidity and storage for the electronics under the bed. After the video, I did more wire management and moved the Smoothie under the print bed. I still have the power supply off to the side because I only have room for one of them without the added storage space. The build is still not complete, since the first print I have only had a few successful prints. The Kossel seems to be working fine but I think the source of my problem is the extruder assembly. The Mk8 extruder drive gear constantly grinds into the filament instead of pushing it down the bowden tube and out the hotend which makes gaps in the prints. As more filament dust/bits get built up in the teeth it gets worse. I have tried many things to remedy this problem, such as a shorter bowden tube, tighter idler, looser idler, and various different temperatures. The cause could be too much friction in the ptfe bowden tube, friction from a unsmooth hotend barrel, or heat creep from no fan on the hotend heatsink/barrel (I have a fan on the barrel). I am testing this printer with a $6 e3d v5 clone but I don't think that this is the cause of the filament chewing as extruding by hand is smooth. I will continue to try things, I have one more idea to test before I test it with a genuine hotend where the quality is assured. Look out for next update!Things I plan to change in the future are: Another triangle, so I can put the power supply under the printerBorosilicate glass, because of two cracked mirror glassesHeated bedNew extruder designNew extruder gearHere is a video of the first print and some pictures from the build: