Anet A8 Print Head Micrometer Height Adjuster

thingiverse

This is an Anet A8 Micrometer height adjuster for the print head. The back half fits directly onto the three linear bearing blocks just like the original aluminium bracket, and uses all original screws for mounting. An adjustable dovetail wedge plate slides into the rear mount and the original Print head/extruder screw attaches directly to this plate using 3mm x 10mm self-tapping screws. A mount is also provided for an inductive sensor, available in 12mm and 18mm sizes to fit a sensor. A piece of 8mm x 1mm fine pitch threaded rod (or 5/16 UNF can be used too) that's 140mm long and three nuts are needed for the variable height adjuster. A thumb wheel with ten graduated markings is used to adjust the height, giving a resolution of 0.1mm (0.004") per graduation and allowing the head 12mm of variable height adjustment. A compression spring 25mm long x 10mm is used to take all backlash out of the design and stop any vibrations. Adjustments can be made while the machine is printing, so if a brim layer appears to be slightly too high or low, it can be adjusted immediately without having to stop printing or adjust the control panel. Adjustments are completely independent of all electronics, sensors, and home switches etc., so once an adjustment has been made, it will remain constant for all further prints. While there are electronic adjustments and updated firmware available, and the sensor upgrade has drastically improved Z-axis calibration, I still find this device particularly useful to make fine and accurate adjustments quickly on the go. The two dovetail wedge parts should be a neat fit, almost snugly so that there's no movement or vibration between the two parts. If they're too tight, just pare some plastic away with a sharp knife until the fit is correct. You'll lose 20mm of Y-axis with the additional thickness of the mount, but you can get most of it back by spacing the Y-axis home micro switch forward as there's some room left on the Y-axis sliders. You can also change the offsets in the Arduino firmware if you're confident editing Arduino code. Just make sure you measure everything and re-calibrate your slicer software for your maximum Y travel and test that you don't exceed axis travel. You'll also need some M3 x 40mm countersunk screws and nuts for the sensor mount and the belt mounting pins. Update: April 8, 2017 - Just added a mount to fit a Bowden E3D-V6 Extruder head that screws directly to the Front Slider Mount at (http://www.thingiverse.com/thing:2236009). Update: 12/4/2017 added a sensor mount for the Tronix XY08n sensor. Update: 8/5/2017 - Just added a sensor mount for a 30mm diameter proximity sensor. It's ugly, but it has a 15mm sensing range, so it's much better and has much more clearance when using a glass table.