K&E 4080-3 Slide Rule Repair

thingiverse

Keuffel & Esser co. Slide Rules made before 1945 are troubled by a material that breaks down over time, like rotten plastic. The glass cursors sit on two small rectangular blocks (one on each side of the rule). We aim to offer replacements so you can repair your rule and make it useful again. Why do this? These instruments helped engineers land us on the moon. Instructions The parts were designed using FreeCAD. I've included the source file. I printed two, with the slot facing up. The slots are meant for a spring that keeps things tight and aligned, but I got almost a perfect fit without one. If it's loose on yours, use some spongy material or a piece of zip tie to create a makeshift spring in the slots. I printed them using a Printrbot Simple 1401 maker's edition with a 0.4mm nozzle, 0.2 mm layer height, and a temperature of 195 deg C at slow speeds. The image I took was from: http://www5b.biglobe.ne.jp/~tomozawa/en/sr-annex/ke-cursor/kercse.htm (My cursor assembly was nothing but dust when I took it apart.)