Workbee gantry modifications

****work in progress**** do not treat this as ready.

25th November 2020
Aliexpress is now advertising 80160 heavy extruded beam for $200USD so the Y plates have been modded to use the 80160 beam with 8 x 8mm holes, a very simple mod. v45 STEP and f3d uploaded as source files.

22nd October 2020
Ballscrews hre being test fitted using 3d prints so they are updated, still only "for interest" step file included as is a 3fd file which needs a bit more cleaning up.

27th August 2020
By all means cut this mk3 in MDF or something as a test and provide feedback.

Please note my work is normally GPL but it is based on the Workbee in which case the Workbee licence takes precedent if there is any conflict. Any residual parts are 100% licence and Copyright of the Workbee creator(s) please respect this.