SummaryIdea was to put this out as an idea but now machine running it appears to be very useable and stable not added latching mechanism yet but simple hole and peg would accomplish this waiting on delivery of Router/milling head which is largest tool to settle on location of Latch and orientation. Ran into my first problem today and although I did not realise it a very slight descrepancy between my X and Y axis on Duo 2.0a, advice for others is print all plates in same direction as receiver to avoid tolerances on this extremely tight to avoid SLOP that may cause poor quality output. Added a mount for Silverline 600w Multipurpose Router still no latch but cut some old 4mm Hardboard as is with 3mm end mill cutter without any problem a little tougher than the foam test but no problems at moment if needed an elastic band under and over mount is the security latch when used a few times and loosens with wear latch will be needed so thats next. My design for a Quick Release head for the Mostly Printed CNC IE version using 25mm conduit, not ready for use yet as I am testing but more of an idea for someone to produce something that could be standard making tool heads easy to design and share. Any comments welcomed if you use it and it works would be nice to know, if you try it and it has a problem let me know and I will try to fix it. Needs a locking mechanism and tool holder to be of use basically a prototype to illustrate an idea. Printed and tried for size and fit of tool plate works nicely for IE version of Mostly Printed CNC using 25mm tubes. Next step add a latch and a tool holder then print a little slower looks like I pushed the i3 a little to fast this time. No play in the slide mount but clearance for the mounting screws will be a problem as it is so will need to add a small countersink. Tool mounts added for Flexible shaft 22mm and 21mm plus E3D V6 print head Cheap chinese copy, Silverline Depth guage for calibration, for testing purposes while still waiting on delivery of Silverstorm 600W 240V 1/4" Multipurpose Router. No Latching mechanism yet picture added (red wire just holding not part of) Have now printed part on three printers Deltabot, Wanhao i3 and Da Vinci 2.0a in PLA,ABS and NuNus Semi Flex PLA, all parts interchanged interference fit but easy enough to use.Print SettingsPrinter: Wanhao i3Rafts: Doesn't MatterSupports: Doesn't MatterResolution: 0.25Infill: 70%