Mostly Printed CNC Bushing Remix

thingiverse

See final update. Don't build this yet, it has a problem. This is a total remix of the Mostly Printed CNC to use bushing. It simplifies many parts to make assembly easier. This design is still in progress and will change. Allted did an awesome job on this, and my design should not detract from his great work. It's merely an alternative for those who want to try it. To build the unit: Print 4 corner pieces (stand upright with supports) Print 4 roller1's (lay on motor mount. No support) Print 1 resizedcnccenterforbushings88 (stand upright with supports) Print 14 endcap's (no support) Print 1 zaxismotormount231 (no support) Print 4 feet Print 1 nutlock The bars are held in place by drilling holes into the bars and using a 3mm tap. Then screw them together with 3mm screws. This unit works with bunting bearings or bushing if you will. They are 15/16" x 1 1/2" long. You'll need at least six of these. Find them here: https://www.zoro.com/bunting-bearings-sleeve-bearing-id-1516-l-1-12-pk3-cb151812g3/i/G3982474/ This design also uses nema 23's. You'll also need a nema 23 to 5/16" screw coupler. My nema 23 shaft size is 8mm, so I'm using an 8mm to 8mm coupler and it works well. Find it here: http://www.ebay.com/itm/5-16-inch-to-8mm-Set-Screw-Shaft-Coupler-By-Actobotics-Part-625194-/281957727216?hash=item41a5fd7bf0:g:hZQAAOSwT6pVsV4I Other than these special items, all other hardware for this unit is basically the same as the original design by Allted. You'll still need 8 608zz bearings, 8 5/16" screws 2" inches long, and 8 5/16 Fender Washers. Get these here: http://www.amazon.com/gp/product/B005DZZC4G?psc=1&redirect=true&ref_=oh_aui_detailpage_o01_s00 Update - 3/20/2016 I'm currently building this thing and making changes as I go to make it easier. I'll also provide any helpful advice. Update - Added a channel guide for better wire management to the roller unit. Now you can hide all wires coming out of the bars. Update 3/21/2016 - Added feet to the unit and an alternative center with bushing for the tool head at request of some people. These bushings are not necessary but if you want them, here they are. To be clear, the file called resizedcnccenterforbushings88.STL is without tool head bushings, and the file called cnccenterforbushingswithtoolbushings.STL has the bushings. Either one should work fine. Update 03/22/2016 - Added a lock cap to the nut assembly to prevent the nut from sliding up. Update - I've tested the x and y axis bushing, and they work great. Very smooth. Update 4/1/2016 - I've tested the z axis, but it's not working as hoped. It's too loose. I need to find some bushings that fit a little snugger. These are 15/16" and close but have some play. I'm putting the project on hold to explore another option. Don't build this yet; it doesn't work. I'll post again when I've devised a solution to the problem.