Hello, I am putting together an Openbuilds MiniMill kit from the amazing anniversary sale. I have a relatively small spindle from my old CNC that has both a 43mm circular mount and a flat mount that uses M6 screws at a spacing of 60x40mm. The router mount is completely off-diameter compared to the circular mount, but there is a 3D printable adapter that is out there somewhere. I don't think the mount would be secure enough given the large diameter difference. The double-wide C-beam plate for the Z-axis seems to have a hole positioning that matches the M6 holes, but may need to be drilled out a bit. The issue is that if mounted directly with those holes, the spindle might be too high on the Z-axis. Also, the C-beam end mounts stick up a little bit compared to the double-wide C-beam plate and the spindle would be blocked if mounted flat on the C-beam plate. I was thinking about mounting another double-wide C-beam plate to the original plate with 3mm spacers in between and offset downwards, and then mounting the spindle to that. I don't have another double-wide C-beam plate so I would 3d print the second one. Does anyone have any other ideas of how the spindle can be mounted? The dimensions of the spindle are in the image below. https://www.damencnc.com/userdata/a...b-p-er11-0-27kw-18000-24000rpm-18014-en-G.jpg Thanks!
If the holes lines up somewhat, even with some addtional drilling, I'd suggest the existing plate > alu spacer > Spindle body via the bolt holes. Spacing it off the plate will help with heat too
If you do find you need to extend it down, do not 3d print an extension. It won’t provide the stiffness this requires. Go to the hardware store or home center and get a piece of 1/4”x3” wide x 8” long aluminum bar stock to make the extension. System stiffness is everything when it comes to the cutter’s ability to cut so don’t do anything that reduces stiffness.
I could not mount directly to the double wide C beam gantry plate because it would be too annoying to get to the back of the plate, and there is no countersink for the M6 screws. I found that if I printed a double wide gantry plate with the mounting holes low on the plate, then an extension was not required after all. However, the spindle did have to be mounted on its thinner side to leave space for the screws to mount the two plates together. The plate was printed 10mm thick to use the M5 20mm screws and 3mm aluminum spacers that were part of the kit.
The build has been completed with the VFD and probe mounted. The lights have been mounted in an alternate location since it just didn't fit the square spindle very well.
