Week11 - Mechanical Design


This week was all about building the MTM Snap Machine. MTM meaning Machines That Make Machines. It is cleverly made with HDPE, the same material as milk bottles, so instead of wood and glue and screws the machine "snaps" together precisely. The material is also remarkably uniform. This piece was 0.5" and didn't deviate at all across the entire surface. One of the first cuts was obviously the most important.




All cut out and ready to go. Following the instructions on the website, this cut took about 5 hours. So plan your time or nudge the speed a little. We got very precise cuts but they didn't seem functionally more precise than the Arch shop pieces and their cut took about half as long. YMMV.






The parts snap out cleanly, having left 1/8" by 1/8" "tabs" to hold them in place, and the nub of the tabs files off cleanly. Once all the parts have been snapped and filed, they are sorted and construction begins.




Here is the XY bed being put together. In addition to doing the cut with Toni and Vernelle, I put the bed together, mounted it on the rails, cut the lead screw, and assembled the whole bed into the main machine.




You can see the hack saw I had to use to cut the lead screw. Not the tool I would've chosen but it was all we had at the time. The lead screw costs $123 so I was particularly careful not to damage the threads. After cutting I cleaned up the threads with a file and took great care not to strip the plastic threads of the lead screw lock nut.


We are currently waiting for the motor controller boards and programming to complete this machine. This design costs about $650 total and is meant to replace the Roland Modella which costs about $25,000. The MTM Snap is capable of the same precision and can mill surface mount circuit boards just as well. It has a small bed size but will work perfectly for PCB and wax milling.




Work and decisions about final projects continue. Node to node communication will be necessary, so this coming week's topic will be vitally important.


So, until next time then, Space Cadets! NovySan, OUT!