I have been experimenting with using MakerSlide to create a mixed lead-screw and rack&pinion CNC router. The project is in a very rough state, but folks may want to build on what I have started, or offer improvements, so it seems reasonable to publish initial results. The drawings are in 3D. Bart's 3D drawings are a great help in trying to figure out how things work. Mine are not as good as his, but hopefully helpful in getting across concepts.
If you decide that you want to build part or all of this project, keep in mind that I have no idea of whether or not it will work. So far it seems promising, but this design uses some parts that are expensive enough that I would recommend trying this only if you are fairly tolerant of having parts made several times and are okay if the thing turns out not to work.
The design is done in Autodesk Inventor 2012. This is my first Inventor project, and I'm sure that my inexperience will show when you look at the files. I have tried to assemble the parts so that they move as they do when actually constructed. A zipped version of the Autodesk files may be found here:
http://dl.dropbox.com/u/24641716/autocad.zip.
I have also posted the design in STEP format. The STEP files may be found here:
http://dl.dropbox.com/u/24641716/cnc-slide.zip.
One of my objectives with this project is to see if I can combine 3D printed parts with MakerSlide. So far, I have been ordering parts from Ponoko. I'm very happy with the speed of delivery and quality of the plastic parts that they have made for me. The current STL files for parts may be found here:
http://dl.dropbox.com/u/24641716/STL.zip. If you have any of these parts made using Ponoko or another service, keep in mind that they are just what I presently think will work. I have had to have several of these parts made two or three times. Even with 3D software to help, I find mistakes. I would not recommend that you have these parts produced if you are expecting them to be right the first time.
My current CNC machine is CNCRouterParts based. I used that to produce the aluminum flat parts that I needed for this design. I have included the VCarve Pro files and individual DXF files for those parts in a zip file here:
http://dl.dropbox.com/u/24641716/DXF.zip. If you are thinking about building a CNC router, then it's very possible that you don't have one already. As a test, I ordered the same parts that I made from eMachineShop
http://www.emachineshop.com/. There is an EMS file that is part of the zip. It cost me around $131 USD to have these parts made. They were produced quickly and are exactly what I expected. If you use the VCarve files, keep in mind that they are in inches while the DXF files are in millimeters. I'm doing this design in millimeters, but my existing machine uses inches. That's why there is a difference.
I have put some photographs of the parts that I have built on Google+. Those, along with some brief notes, may be found here:
https://plus.google.com/photos/101440406689536737329/albums/5734777303367817569.
I really like DumpsterCNC parts. You will see those in the drawing for the Z axis. It's a close fit, but it looks like they will work.
It seems that a Bosch Colt router is about the right size for this build. I got my mount from K2 CNC
http://k2cnc.com/shop/products.asp?cat=31. The Colt mounts seem to be out of stock at the moment.
For dust collection, my plan is to go with a Kent CNC shoe
https://www.kentcnc.net/nc/. I hope this works with the Z assembly. I should find out in a week or so.
My current machine has spindle speed control, which I really like since I cut plastic, MDF, and aluminum. My thought is to use a SuperPID controller
http://www.vhipe.com/product-private/SuperPID.htm for the Colt.
The drawings don't show the right stepper motor. I tried the Vextra from Automation Technology (part number in drawing), but that one did not seem right, so I am currently using the KL23H276-30-8A
http://www.automationtechnologiesinc.com/products-page/nema-23/nema-23-14-single-shaft-with-flat-282-oz-in with a Gecko G540 that I also got from Automation Technology.
There are quite a few parts from McMaster and Misumi. The rack&pinion, aluminum extrusion, and extrusion connectors are from Misumi. The part numbers are in the drawing. At present, I don't have any plans to put together a bill of materials. There are, for the most part, no screws and nuts shown in the drawings. Sorry about that. If you build some of this, you will probably have to do what I do and have lots of M5 and M4 socket cap screws, lock washers, and flat washers in front of you.
There is a, hopefully minor, annoyance with the drawing. I don't know what I was thinking, but the X and Y axis should be swapped. I am leaving that alone for now as it appears to me that this would be a major re-work of the drawings. When I wire the device, I think that I will swap the X and Y.
I hope all of the URLs work properly. I have not previously used Dropbox or Google+ to share files. I'm happy to upload them here, but a few of the files are big and upload attachment did not seem to like them.
When I get some time, I will post a few of the pictures individually, along with some comments related to what has worked and some problems that I have encountered.
My hope is that I can test some basic cutting in a month or so. I have run out of V Wheels, but have some on order from Inventables. The rest of the aluminum extrusion for the project arrived from Misumi yesterday, so it should not be too long before I can test cutting.