Summary

This is a mount for classic Rostock 3D printer to allow quick change of hot-ends and other tools on your printer.

I took the idea from RichRap Quick-Fit But it's not compatible because Rostock platform is smaller than RichRap's Quick-Fit carriages.

Design created in OpenJSCAD.org

Instructions

print all parts - holder-1, holder-2, latch, key
print mount-template or develop your own mount based on provided .SCAD file or .STL
use MR105 ZZ Model Miniature Ball Bearing 5X10X4 for the latch
use 4 M4 screws and standard holes in Rostock platform to assemble it

Universal E3D / J-Head mount can be used with E3D or J-Head ver 5-6 hot-ends

print qf-jhead-e3d-mount-plate.stl and qf-jhead-e3d-lock.stl
insert PTFE (4mm) into the center hole
attach M4 nut to the tube and push the nut down into the mount
insert hot-end
use one of two holes to lock the hot-end , use lower hole for E3D or another one for J-Head

qf-jhead-e3d-mount.scad provided for modifications.