19 November 2012

Coffee machine handle

The handle for the coffee machine broke at work, and I had a 3d printer!

I designed and printed a replacement handle. To save plastic the centre of the handle was hollow. Where the tongue of the coffee cradle inserted into the handle was more complicated. It didn't print very well. Fitting the handle I had to dig out a lot of plastic and force them together. Then, once it on it was a lose fit. Sticky tape padded it out again and made it snug. 

I was using new plastic which clearly needed some tweaking of settings. I used the temp where plastic started dripping out the extruder, which I thought would be enough. It was the same setting for which I had also printed some calibration pieces with rather bowed bridges.  While printing the temperature kept falling below the extrusion cut-off limit and it would report “cold extrusion prevented”. Towards the end I turned up the temperature higher. For some reason I also turned off the heated bed. It also didn’t seem like it was extruding enough plastic and became concave. I tried increasing the extruded step rate mid print, though I am not sure if it did anything.

All in all it seems ok, but the very end of the handle seamed the most consistent. By comparison the rest of the handle seams patchy and lighter grey.  I figure that the higher temp allowed the plastic to correctly melt, adhere to the previous layer, then set. Whereas at the lower temp remained somewhat solid and less malleable plastic was just being squashed together just enough to hold.