RepRap: Blog

Here's a photo of the Z-axis pulley rim that fits on top of the Z axis gear. I've pulled off all the stringy bits and reamed the holes out with just a drill bit held in my bare hand to clear the thin cruddy bits out. As you can see, it's not too shabby.

I've tried printing a corner bracket and got about 70% the way through before a new and unexpected software state was encountered. Ahem, cough. Beyond my ken, but Adrian will be back soon...



Anyway, here are the modifications I did to the Darwin to get PLA coming out.

A. Oily rag in holder to lubricate filament.
B. Large 12V motor to push filament through.
C. Fan to stop polymorph motor holder melting.
D. Polymorph saddles to stop excessive rotation of carriage.
E. Clamp to apply extra pressure to filament.
X. That's a label so I remember which one is the X-axis motor...

You can't see it in this photo, but also I flopped the extruder "umbilical cord" over to the side so that it doesn't tangle with the filament feed.

Vik :v)

Labels: pulley, reprap, rim, z-axis

I tested a bit of Darwin today. I asked the Z to go up and down 20 times, putting the motor through 1000 steps for each stroke. This, in theory, would only move the bed up and down by 3 mm, but there was some timeout error going on in my code, so that's as far as I could push it today. Testing over a big range is on the list, but it's repeatability I'm interested in, so 3 mm will do for now.



The motor torque was at 100%, speed 200 (see exerciser scale - approx 80%), and the results on the caliper bolted to the bed were... well... the graph can do the talking:



Happy days! I guess that puts the resolution at ±0.01 mm. There's still the X&Y to get moving yet, but it's good to know they're on solid foundations ;-)

Labels: darwin, performance, z-axis