XY Plate & Heat Spreader Bar

Short XY Plate cut from 3mm thick aluminum plate. Short XY plate is based upon the DXF cut file,

 

xstageshort.dxf

 

found as a download of Thingiverse Thing 252041,

 

www.thingiverse.com/thing:252041

 

Use the short XY plate if you have a short NEMA17 stepper motor such as those MBI uses for their extruders. If you have a stepper motor with a bigger stack, then you may need to use xstagequ_bd.dxf.

 

The aluminum heat spreader bars are the proper 0.5 inch thick ones MBI uses on the Replicator 1 and 2 series. They provide far more contact area with the thermal barrier tube than the Mk7 style heat spreader bar. Unfortunately, a number of the Mk-style extruder kits provide the Mk7's thinner heat spreader bar (e.g., QU-BD's MBE v9). If you plan on extruding PLA, you want the thicker bar! Otherwise, you will likely experience jams on long duration prints.

 

Robotdigg.com and dealextreme sell the thicker bars BUT only one of the holes is tapped for M6 threads. Use that hole for the thermal barrier tube. The other hole is smooth bored and will accept a M6 bolt. Cut a M6 bolt to a length of 19 mm. (I do it by threading 4 M6 hex nuts on, cutting flush to the fourth nut, filing the cut end, then removing the nuts. (Having the nuts on helps you clean the cut threads after cutting.)

 

A hand cut slot has been made in the XY plate with which to affix the heat spreader bar using the cut M6 bolt and a thin M6 hex nut.

Done