So I just finished my build, and have some points to make and I hope the people from carbide listen. I’m not trying to come off as a jerk or anything but inform them of some things.
The cutting area of the XXL is not 33x33 like advertised. With the router installed and moved all the way back I can realistically only see about 31 inches of usable Y travel all the way up to the front guard. Similarly for X travel, I can only use about 32 inches. I am slightly upset about this as I was planning to use all 33 inches of the cutting area.
The kit does not come with all the tools needed for assembly. Not that this was a big deal for me, but I had to use my own wrenches for the homing sensors.
The instructions had several holes in them. Especially with the wiring. after doing some searching, it seems that people have been complaining about this for a long time.
Question:
Does anyone else have issues with moving the axis manually while the system isn’t powered and it fighting back? I figure that manually moving the stepper motor is generating power for the controls board, and generating enough power that the stepper motors fight back. When I manually move the system with the power off, the control board lights up and I hear the windows finding a new USB device. Has anyone experimented with diodes wired in so that you can’t send power back to the board? I would like to be able to manually run my system for planing and what not.
Yeah, I do have to agree with you on the cutting area. Not in front of my machine but those numbers sound about right. I was a little miffed about this as well, but less so as I didn’t have a specific project in mind when I discovered it.
Again, not in front of my machine, but iirc, I think I have soft limits set around 831mm x 792mm, so ~32.72" x ~31.2"
1 - the cutting area measurement includes the overhang off the front of the machine – some users have added plates which extend the flat are to include these, others use the area at the front to cut oversize pieces mounted at the front of the machine, esp. boards clamped vertically to cut dovetails. The wiki Shapeoko CNC Router, Rigid, Accurate, Reliable, and Affordable addresses this by noting:
Cutting Area (note that this includes a 2 3/16" overhang area at the front of the machine)
Metric: 425mm x 425mm (note that Carbide Create limits this to 406.4 x 406.4mm)
2 - the limit switches are a recent addition to the standard kit — not sure if your tools were left out, or there’s a gap in the list. Please let support@carbide3d.com know. FWIW, the community was maintaining a list of tools at: Shapeoko CNC Router, Rigid, Accurate, Reliable, and Affordable — this needs to be updated, and hopefully it will happen as part of the below.
3 - Hopefully there will be a new set of instructions presently.
To answer your question — Yes, the stepper motors generate electricity, and one should not push the machine by hand. The idea of using diodes to prevent the blowback into the stepper drivers is an interesting one, but it’s not one which we at Carbide 3D can support due to liability issues. I will further note — if you want a planer, or a router table, buy one, or use the machine to make one. Our operating checklist specifically notes: http://docs.carbide3d.com/article/41-machine-operating-checklist
Do not reach into the machine’s working envelope, nor insert any object into it while the machine is operating.
You can’t just add a diode in the wiring between the board and the steppers. The current flows both ways much like an AC motor. You’d have to design protection into the board itself (probably before the actual stepper controllers)… which would add to the cost.
If you truly want to move the device freehand, just unplug the steppers from the controller… but I think it would be easier to make a job that does planing you want (large rectangle, create a pocket, set depth, done)
I’m just curious, what did you need the FULL 33" for that 32 isn’t going to cover for you?
No comment on missing tools… other than that I’d rather they not include tools at all and instead say “you’ll need these tools for assembly, so go get a set” to encourage people to go buy a good set of tools they’ll likely need anyway…
I had done the original So3 assembly manual last year, but they haven’t requested an updated version to match the updates & expansions to the machine. But, if you take photos and annotate them regarding what in particular needs mark-up, I’d be curious to see it, and I’m sure that doing so would also help them get that content sorted out better.
Regarding moving the axis when the machine is off, I’ll second what @WillAdams & @r3dey3 have said, but also note if you’ve got the power off you can disconnect the USB and move the gantry slowly without fear of damaging the electronics, and prior to installing homing switches it’s actually the preferred way to “zero” the machine for a job—put it where you want it in the work-envelope relative to your material (according to your CAM setup), and then turn everything on, tell it you’re at “program zero” and start the job.
I would also recommend against trying to use the machine as a manual machine-tool, because any forces over the limits of the holding-power of the motors & belts generated by user-action will cause the router to move on one of the axes by either “skipping teeth” on the belts or back-driving the motors, and this is not good for the machine OR your work-precision, if a tool suddenly bounces out of—or worse, into—your workpiece.