Several months ago after slightly reworking the wiring to the J-head, the thermistor slipped slightly loose from its socket in the heater block. The temperature monitoring code in the controller will detect a short or open connection on the thermistor and shut down the heater, but it can't do anything to detect a thermistor that is simply no longer thermally connected to the block, and the heater stayed on long enough to drive the heater block far above its normal operating temperature. I...| Drew's Robots
First layer adhesion seems to be the key to getting a good print out of this printer. If the first layer sticks evenly and consistently, and stays stuck during the print, the print usually comes out well. If the corners detach, they tend to curl upwards, deforming the part, and in the worst case interfering with the movement of the print head. When a delta printer skips a step, it doesn't just shift the layers above the skipped point sideways as it would in a normal printer. A skipped...| Drew's Robots
With a working extruder, and after MakerFaire a reel of black 1.75mm PLA filament, it's time to try printing. So I drew up a standard 20mm calibration cube in AutoCad, sliced the stl into Gcode with Slic3r, and sent it to the printer in Pronterface.| Drew's Robots
This started out as an Airtripper extruder, but I decided to tweak the design to better fit my printer and the parts I had on hand, and by the time I was finished it was nearly unrecognizable.| Drew's Robots
For my printer's hot end I chose a Mini J-head Mk II, custom-made by hotends.com. The standard J-head is designed for 3mm filament. I liked the simplicity and light weight of the J-head, but my printer is intended to use 1.75mm filament, so I custom-ordered a mini J-head instead. I had been considering an Arcol.hu hot end at first - liked the idea of an all-steel extruder - or possibly a Budaschnozzle, but the Rostock design really calls for a head that's as lightweigt as practical to m...| Drew's Robots