3D printer – first test


After some initial tuning we did three test-prints today of a 10x10mm square, 30 layers, raising the z-axis by 0.5mm for each layer. We tried to set it up so that when the X or Y-axis moves 10mm, the extruder A-axis should also move 10 units. The way it is set up right now it might be extruding slightly too much plastic per mm. The maximum feedrate we tried was 600mm/min.

We printed the same geometry three times, here is the second try (in the first try the base/bed wasn't staying very fixed, so the print resembles the leaning tower of Pisa...)

Here is the third try. Now we are moving the Z-axis +0.5 mm during the last Y-axis move. This is at 600mm/min.

We were pretty happy with the print-quality so far, considering this is the first ever test of our extruder/xyz-table setup. Some tuning of how much plastic is extruded for each mm of xyz-feed, and perhaps a heated printing-bed, should improve the quality further. Next is learning to use one of the many STL to G-code CAM programs and filtering the G-code output so it is suitable for our EMC2 setup (the extruder is the A-axis, in absolute mode).

Update: Risto has more on this in his blog: ?http://risto.kurppa.fi/blog/2010/12/first-prints-with-reprap-the-open-source-3d-printer/

Extruder test

The temp-control electronics, together with a stepper motor controller, have been packaged into a box, and I modified the EMC2 config to include an A-axis that controls the extruder stepper motor. The extruder seems to work, but the big cog-wheel that feeds the ABS plastic rod could be improved. It now slips a little too easily, especially when the corrugated area which pushes against the plastic rod fills up with small bits of plastic. Next up is mounting this on an XYZ-table and trying to 3D print something!

Links - 2010 Dec 12

Winter running

When the going gets tough... ...the tough go running in icebugs

I've done a few 10k runs and some 1k repeats indoors on the treadmill at the gym, but for the long-slow-distance type of runs it's really much nicer to go outside. These shoes with spikes (Icebug ATTLA) provide added grip on harder snow and ice surfaces, although they are pretty slippery on an indoor stone floor. They are warm and waterproof although towards the end of today's 14k it felt a bit like running in rubber boots (there is a trade-off between waterproof and breathability I guess).

Running in loose snow is a bit  like running in loose sand on the beach. You spend a lot of effort and go almost nowhere! Today's pace was a minute or more slower per km than usual.

It's not unusual for us to have this much snow, but it is maybe a month or more earlier than normal.