darran
05-18-2018, 06:58 PM
A couple of months ago I joined Vancouver MakerLabs (http://www.makerlabs.com/). After taking their intro CNC course, I have spent a fair number of hours learning Fusion 360 and working with their little Shopbot Desktop. The Shopbot had fallen into a bit of disrepair. The existing spoil board was a minefield of deep grooves and screw holes where people had respectively cut too deep or secured their work-piece with all manner of screw fastener. I set about creating a new board, replete with a 2" x 2" grid of dog holes backed with 1/4" 20 tpi T-nuts. I modelled and created the CNC tool paths for cutting this spoil-board in Fusion 360. The fixtures holding the board down at the edges are temporary - these secured the board while the internal hold-down slots were being milled. (I've gotten into the habit of modelling all fixtures accurately so that Fusion's CAM system can detect collisions.)
Moving on, what use are dog holes if you can't leverage them ... so I similarly created work-piece hold down cleats and side-pressing cam clamps. (Note, neither of these are my own design. See here (https://www.youtube.com/watch?v=9WfI9C_Zpmo) and here (https://www.youtube.com/watch?v=O-rqf4uSXRE) for the YouTube videos detailing the cleats and cam clamp designs respectively.)
I also fabricated a new male base plate for the Shopbot's broken dust shoe holder. I started with a flatbed scan of the matching female half of the dust shoe assembly. I then brought this into Fusion 360 with the Attached Canvas, calibrated against a known dimension and quickly created a highly-accurate sketch. Extrude the part, over to the CAM environment to create an SVG file suitable for laser cutting, and soon after we had a new base plate made from 6mm acrylic. I glued in the magnets and the dust shoe mount was back on the machine.
Finally I added a unistrut support for the dust extraction hose and MakerLabs' Derek Gaw added a strip of white LEDs to provide illumination for this portable machine. Now that the "meta making" is complete, I'm ready to get back to designing and CNCing something real.
An image gallery showing the results can be seen at https://gallery.autodesk.com/projects/shopbot-desktop-tlc. (If you'd rather I add the images directly to this thread, just let me know and I'll update the post.)
I love this little machine ... despite having broken my first bit yesterday. Totally my fault obviously: I was rushing and made a CAM setup error.
Moving on, what use are dog holes if you can't leverage them ... so I similarly created work-piece hold down cleats and side-pressing cam clamps. (Note, neither of these are my own design. See here (https://www.youtube.com/watch?v=9WfI9C_Zpmo) and here (https://www.youtube.com/watch?v=O-rqf4uSXRE) for the YouTube videos detailing the cleats and cam clamp designs respectively.)
I also fabricated a new male base plate for the Shopbot's broken dust shoe holder. I started with a flatbed scan of the matching female half of the dust shoe assembly. I then brought this into Fusion 360 with the Attached Canvas, calibrated against a known dimension and quickly created a highly-accurate sketch. Extrude the part, over to the CAM environment to create an SVG file suitable for laser cutting, and soon after we had a new base plate made from 6mm acrylic. I glued in the magnets and the dust shoe mount was back on the machine.
Finally I added a unistrut support for the dust extraction hose and MakerLabs' Derek Gaw added a strip of white LEDs to provide illumination for this portable machine. Now that the "meta making" is complete, I'm ready to get back to designing and CNCing something real.
An image gallery showing the results can be seen at https://gallery.autodesk.com/projects/shopbot-desktop-tlc. (If you'd rather I add the images directly to this thread, just let me know and I'll update the post.)
I love this little machine ... despite having broken my first bit yesterday. Totally my fault obviously: I was rushing and made a CAM setup error.