Drag Knife Holder

thingiverse

I have many platforms that I pursue with much joy. I have added 3 D printing as a new platform which made learning more about CAD and STL file development. I have a CNC table that I use for Plasma cutting and Routing of different materials. I have build an optional Drag Knife holder to attach to the router on the table. It worked well but when I added 3 D Printing I though this is a great opportunity to develop a new holder. The process started with a CAD drawing and then moved to 123D Design to convert that 1 drawing into 3 separate STL files to be printed. The DFX file was the base and I either extruded sections or subtracted other sections and then manipulated each of the 3 parts to a final shape for printing. This assembly is designed to float the drag knife using its own weight to cut through the vinyl but not its backing paper. The linear shaft and bearings allow the blade holder to move freely up and down very smoothly. The blade swivels inside of the holder as it changes direction to cut all shapes in the sign vinyl. I bought 2 – 8 mm linear bearings, 1 hardened 8 MM and the Drag Knife holder from eBay shown here. https://www.ebay.com/itm/300-500-350-400-450-8mm-Linear-Motion-Shaft-Hardened-Rod-3D-Printer-CNC-Prusa-i3/152143072244?ssPageName=STRK%3AMEBIDX%3AIT&var=451338987453&_trksid=p2060353.m2749.l2649 300 mm which was cut to make 4 shorter shafts https://www.ebay.com/itm/Roland-Blade-Holder-for-Cutting-Plotter-Vinyl-Cutter-Sign-Making-Machine-4/111813114847?ssPageName=STRK%3AMEBIDX%3AIT&_trksid=p2060353.m2749.l2649 this is a #4 blade holder with has a 11.5 mm OD body size. https://www.ebay.com/itm/6-PCS-LM8UU-8mm-Linear-Ball-Bearing-Bush-Bushing-For-Rod-RepRap-3D-Printer-L-JB/253458898103?hash=item3b0353dcb7:g:EgoAAOSwa-dWjp9w 2 needed for each finished Drag Knife holder assembly. I pressed the bearing into the holder section and then used it to help keep the shafts in alignment with the other 2 section as they are pressed together for final assembly. The 2 holes in the bearing section are to be taped with a 10-32 tap. This is to attached a mounting plate for mounting to the CNC table. https://www.youtube.com/watch?v=gn1Xh9PaInc&feature=youtu.be reports the video did not work here is the address for it to try I remove the on below now.