Hi All,
Fusion 360 CAD Files (view or download)
Cost Breakdown and full Parts List (google spreadsheet)
I'm planning a CNC router build for 3D carving of wood, V Carve inlay work, some aluminum work, plastics, etc.
I have a few years of experience with industrial routers (Anderson Stratos) so I want it to be fully featured: Automatic Tool Change, Good dust collection, vacuum table, 0.001" precision, high rigidity and reliability.
This forum has been incredibly helpful for me so far, so hopefully by giving away the design files and cost breakdown here I can help other people as well.
Frame: 200x100mm and 100x100mm GFS extrusion from Misumi. I plan on filling the extrusion with epoxy granite to reduce vibration.
Misumi Extrusion
The aluminum plate used throughout the build is 1" ATP-5 (similar to MIC-6) tooling plate.
Spindles I'm looking at are the Jianken 2.5kW or Mechatron 2.2kW, both water cooled. I'm thinking I could just put a 100 gallon water tank on below the table, which would add 850 lbs of weight to the machine. I'm concerned about using ISO20 tool holders, as these are rare and don't support 1/2" tooling, still waiting on quotes from both companies though...
Mechatron Spindle
Jianken Spindle
Linear motion will be 2010 Ballscrews and 25mm Linear Guideways. 2 Ballscrews on the X axis (stationary axis), 1 on Y (gantry), and 1 on Z axis. I plan on using the FK/FF style bearing block rather than the BK/BF style, because it seems like these would have a more sturdy connection to the frame.
Drive motors will be either 180W JMC servos or their larger 400W versions. These are integrated servos so they don't require additional drivers.
JMC 400W
Controller would likely be UCCNC 300ETH-5LPT and UCCNC Control Software
Things I'm still figuring out and would appreciate any help with:
1. Does this design seem sufficient and sturdy enough for the things I want to do with it? General critique of the design appreciated.
2. Deciding between using 1" HDPE or 3/4" Aluminum plate for the table bed. Benefits of HDPE are it's easy to machine and about $350 rather than $1000.
3. Help with spindle choice. It seems like ISO30 or HSK25 Tool Holders are way more common than ISO25 or ISO20. How big of a concern is this? Should I limit spindle options to only more common tapers?
4. Help selecting a quality VFD. I know Huangyang is popular but obviously their quality is low. I don't want to be fighting a low quality VFD, does anyone have a recommendation for better quality ones around 2.5kW in the $300 price range?
5. Help selecting power supply for the motors. The (400W) motors are listed as 6A, 24~50VDC (36V typical value). This isn't my strong suit, any good power supply recommendations that would accommodate these motors?
Generally do these CNC routers only use 1 large power supply for all drive motors or do they use one for each motor? For some reason I haven't found an answer to this question yet.
6. Ballscrew technical details! Because I'm using the flanged rather than pillow style blocks, I won't have any adjustment for length of the ballscrew, is this a concern? Let's say there is 1700mm as drawn between the two bearing blocks. With machining on both ends how do I know exactly what size or order the screws at, and if they come in 1mm (or whatever) too long or short will this be a big issue? I've never installed ballscrews before.
7. Any good vacuum pump suggestions? Have any of you successfully implemented vacuum hold-down and would be willing to share any insights on the best ways to go about it?
8. Any recommendations for what kind of electrical cabling I should use throughout the build?
9. Looking at the cost breakdown spreadsheet, for my benefit and anyone else who might want to build this or a similar machine, are there any glaring issues or things I've overlooked?
The model is parametric, so after downloading the model in Fusion 360 you should be able to adjust the length, width, height, plate thicknesses, etc. using the "change parameters" tool.
Thank you all for your help!
Ben