I decided to build a dedicated frame & enclosure for my Liteplacer rather than mount the machine to a table like it was designed. Since the plan is to add feeders and other features over time as needs evolve, the added cost of 80/20 extrusion seems justified. I had previously designed the frame in Solidworks and the extrusions were ordered cut to length. All that was left to do was drill a few holes, tap some of the ends and assemble.
Speaking of tapping… why is it that you never seem to break a tap when you have a spare? But always seem to when you don’t. Murphy’s law of course came into play… and I ended up donating my only 5mm tap to the scrap bin.
Putting this all together necessitated the manufacture of several parts. A total of 12 custom brackets were manually machined on the ole Bridgeport. Mounts for the footpads, monitor, PC, and the brackets to mount the Liteplacer into the enclosure were created. There is something uniquely satisfying about using machinery to build more machines, but all the handle turning really had me wishing for a CNC… more on that in a future post.
The Liteplacer mounts into the frame with a machined bracket at each corner. I also made up a center bearing support out of some 0.125″ aluminum. This supports the Y axis shaft center bearing from the frame, and allows removal of the Liteplacer’s rear crossbar.
With the machine mounted, it was time to wire it up. Continuous flex rated cable was used for all the moving runs of wire. I found some Trex-Onics 18AWG / 6 conductor shielded cable on ebay that was reasonably priced. The axis motors and limit switches were all wired in using this shielded cable. The cables were terminated at the control end using Amphenol C 091 A Series connectors to mate up to the control box.
The Y axis cable carrier ran a little long for my enclosure and was going to hit the front cover when the Y axis came all the way forward. I cut a piece of 0.125″ aluminum and formed up a relocation bracket to move the mounting point rearward which afforded me plenty of room.
While the 80/20 extrusion is really nice for it’s adaptability, it doesn’t make for a particularly rigid frame without cross bracing it. You’ll notice in the picture and rendering at the top of this post that I’ve added some aluminum panels to the bottom, rear and sides of the machine. In addition to better enclosing the machine, these serve as structural elements, effectively cross bracing the machine in all three directions. The polycarbonate covers on the upper portion of the machine will also add a bit of rigidity, albeit to a lesser extent than the aluminum panels.
The plates are 0.125″ 5052 aluminum, and the pan that sits just under the open bed area is 0.080″. These parts were laser cut at a local shop that also did the forming of the “bed pan”. The polycarbonate covers are 3/16″ thick, and used up an entire 4′ X 8′ sheet. I laid these out in Solidworks and pestered my buddy Jon until he cut them on his router table.
Most of the polycarbonate covers won’t be installed until the rest of the details are sorted out and the machine is up and running. I’ve got at least one or two more posts worth of details to cover before the machine is finished. I still need to build and mount the vacuum reservoir. I also need to build circuit board and parts holders. Then it will be time to load software and start placing components. Thanks for reading and keep an eye out for updates.