CNC Circuit Mill/Research Development
Developers
- Yoonseo - ykang404(at)gmail(dot)com - Kanada - English
- Mister Scr3wdriv3r - mister.scr3wdriv3r(at)gmail(dot)com - Germany - Freiburg - English, German
Mailinglist
- ose-cnc(ät)googlegroups[dot]com
Conference Meeting
Via Skype. Ask for skype contacts via mail.
Next: 10pm CET March 29, 2012
We use Tortoise HG for Revision Control. Here you can see a little tutorial about tortoise, available for linux and win.
- /.hg - includes the revision database
- /brain_StOrm - good to put pictures, drafts of any idea
- /CAD - includes the Prototype Folders
- /CAD/YYYY_MM_DD_Name_001 - includes the SolidWorks CAD Drawings
- /Documents - Documents in general
At any file yout put inside please use the prefix YYYY_MM_DD_ on the creation date and clear title what is inside of the file.
Resources
What Programms and Hardware we use:
- Google Sketchup
- SolidWorks
- Arduino
Accounts
- dropbox
- flickr
- googlegroups
- to be fullfilled
Research
- CNC
- CNC Software
- CNC Circuit Mill Discussion
- Circuit Mill Problem Statement
- Ultimaker Pick and Place
Ideas
If it's going to be a dedicated circuit mill, as opposed to a generic tabletop CNC that happens to be used for circuit milling, then it should have more functions. With only a modest increase in complexity it could have a copper board "magazine" and a mechanical flipper that would automatically position an arbitrary number of two-sided copper boards to be milled on both sides. Perhaps the router bit can also be used to drill (route) some of the holes; at least the mounting holes. Both a router and drill can be mounted on the gantry. The router can be solenoid controlled (down to the right height or up and out of the way). The drill can be on the z-axis so it has full range of motion.
- The Red Blue CNC mill was Nick Santillan's graduate project. It is made up of three identical axes with holes every 3.5", allowing them to be reconfigured modularly. At his blog and Ponoko and Design Boom and core77
- Open Source CNC Mill - Design already exists!
See Also
CAD of Mobile Gantry Design (In Progress)
X Axis Frame Design Rationale
- The major functions of the X-Axis Frame are to provide a flat working platform on which to rest boards to be milled, and ensure the rigidity of the X-axis precision shafts and leadscrew.
- Start by assuming that the x-axis frame needs to support a pair of precision shafts and allow mounting of the working platform and stepper motor with leadscrew.
- The working platform has to be some sort of flat sheet or plate.
- Some sort of rectangular support structure seems a good start, with a total part count of 5.
- Here is an visual example using 1 plate and 4 rectangular bars:
- This is rigid and has space at the sides for gantry mounting, but bulky. We notice that a lot of material is still being used despite the low part count. Keep in mind that part count and material volume, future design implications, and ease-of-manufacturing must all be considered separate, though interrelated factors in effective design.
- If we use only 2 rectangular bars (for supporting the precision shafts), then we can save on material volume by using 2 angles as structural supports.
- Here is an visual example using 1 plate, 2 rectangular bars, and 2 angles:
- This is relatively volume-efficient, with plenty of open space at the side for gantry mounting. The major concern with this design is that the resistance to force vectors is heavily dependent on the angle supports, which significantly lose mechanical advantage as the rectangular bars get taller. Low-profile setups will be best for this design.
- Here is another take on the 1 plate, 2 rectangular bar, 2 angle setup. What if the angles were to mount the precision shafts instead of the rectangular bars?
- The major concern with this design is the vulnerability to forces with strong vectors along the horizontal plane. Again, low-profile setups will be best.
- For completeness of the practical variations of the 5-part x-axis frame, consider the use of 4 angles and 1 plate:
- The major concern with this setup is that the angles, though volume-efficient, will not provide enough rigidity at their 4 junctions.
Gantry Design Rationale
- The gantry needs to be mounted at 2 points per precision shaft for stability, as well as somehow being connected to the movement of the leadscrew nut.
- Starting from the x-axis, assume that the 2 precision shafts and 1 leadscrew are firmly mounted. One C-channel per precision shaft gives us the 4 contact points necessary per axis; 1 angle centred at the leadscrew and across the C-Channels can make the connection. A flat bar for the C-Channels can provide rigidity along the plane perpendicular to the precision shafts.
- Here is a visual example (note that the square bars should be seen as round instead):
