Quote Originally Posted by soofle616 View Post
I've been thinking along the same lines recently. Unfortunately, while I have the mechanical and design prowess to come up with a variety of solutions, I don't have the programming knowledge to make any needed changes to the firmware for an active head retraction method. Something passive like your spring retract might work though.
Maybe between us we can come up with a solution - if time ever allows! A good read here: http://tinyurl.com/prr48wy regarding extruder forces, seem to be in the 1 to 3Kg range.

I have one of the Airtripper extruders for a 3D project I started a while back and hope to finish one day (this is as far as I got: http://tinyurl.com/ouzpgba ) but two house moves and two more to come next year have put that project on hold. I recently bought the FFCP as a stop-gap as needed parts for my main project (http://www.cine2digits.co.uk/). It was for this project I discovered that a thin white ABS layer (0.4 to 0.6) makes for a good diffuser with performance not to dissimilar to expensive, and soon to become extinct, flashed opal glass. The problem of the head(s) dragging across the surface is not tolerable for this application!