Summary Geoffs_Simple_Spool_Restraint.scad A simple design in openSCAD to prevent the Filament spilling over the Spool's side - it's very annoying and happens (to me !) when I have a very full (or loosely wound) Spool of 1.75mm filament. The weight that prevents the spilling over can be anything - I used a scrap piece of Nylon (approx 10mm x 20mm x 300mm), but anything that's slightly slippery could be used. shapes.scad is available at http://svn.clifford.at/openscad/trunk/libraries/shapes.scad This design relies on the Solidoodle Spool Holder Mk2 by gsterley ( http://www.thingiverse.com/thing:97734 ), but can be easily modified (in openSCAD) for many similar spool holders I initially thought of extremely complicated kludges with springs and elastic, but settled on gravity as being much simpler - and it hardly ever fails :-)