Raptile

This might like an unlikely blog for nerdy stuff, but then, always expect the unexpected. Maybe it's more a story about persistence than about technology, be warned though, I will mention nasty tech stuff.

Some month ago I heard about 3d printing, and got on a mad internet hunt to find out more. The reprap series took my liking, and I found someone in Adelaide that offered ready built Prusa Mendels for a reasonable price.

However, by some stroke of fate my machine arrived elsewhere, and the replacement machine came with a broken z-axis connector. The dream of plug'n'play was gone, well, I knew beforehand that setting up a print host would be enough of challenge, but instead of figuring out 'soft' problems I needed to get out spanners and screwdriver to get things back into action.

Luckily, I received a good amount of spares for the broken part, although I couldn't find too much documentation about the bits I needed to do. Some glued parts were in the way, and I didn't feel too confident in my fixing attempts. It took me literally ages to level the printer, and to dare to connect to its supposed host.

Dealing with Windows installation of Java, Python and some more bits and pieces turned into a nightmare. I relived my frustration that I experienced during my first professional exposure with Windows 1994: An orgy of badly organised system structures and confusing dialogue boxes, an utter lack of common logic, a training in obedience to the machine.

Anyway, the mechanical setup looked okay, what did I know, I never saw a 3d printer in action before. And after remembering that problem-solving with win software usually meant deleting everything and starting over, taking care each step in down in the right sequence, I got a bit further in having something like a printer interface up and running.

I think it took me only half a day to have figured out how to talk to the printer via the interface, and I could dare to see it moving. I could move x and y axis fine, I didn't understand how to move the z-axis. When I used the z-home function, disaster stroke. The side of the z-axis that had survived the transport crashed down, and without a z-stopper (which I moved out of the way without knowing what it was) the z-steppers kept spinning and spinning, until I removed power.

I waited until the next day to get the spanner and screwdriver, replaced the connector with a spare, which took quite some reaming, and had another go. However, in my attempts the night before I changed a driver setting (it's a not a nix system, it still needs to reboot to learn new things), which effectively removed the usb-to-serial driver.

Three or four reboots later I was where I was the night before: A 3d printer that seemed mechanically okay, a software talking to it, and eager to get this thing to print something. I pushed the connect button, and saw the 'start' reply from the printer controller. I spend some time moving the extruder along its axis, noticing that it was tricky to level with the print surface.

When I got ambitious and tried to print, the feeder for the extruder moved, but the temperature sensor for the hotend always showed 500 degrees, and nothing seemed to happen. I aborted printing, and played with the manual switches for hotbed and hotend, yet the mystery remained.

Then the next disaster stroke. While I tried again the homing functions, strange noises occurred while moving the y-axis, and a nut rolled underneath the printer. I was happy enough to print a model on the edge of the build platform (still haven't figured out how to move around with the print tools), and then the y-axis belt came off.

While my hope went up during the last couple of days, the number of obstacles seem to multiply. Even the small model I want to use as test needs plenty of PLA, but as yet I haven't really seen it moving at all. So while I'm relatively confident to fix the y-axis (relatively), the extruder looks like a bigger problem.

At least I had the opportunity to revise my OpenScad skills. Surely, I could use an online printing service, but I'd rather do this after fine-tuning (rapid prototyping, innit) at home. So tomorrow, it's back to some real tools, while searching the interwebs for info about hotends and temperature sensors.