I’m running VCarve Pro to Carbide motion on a Shapeoko 5 Pro. I love this machine, HOWEVER, I get very small changes in Z height while the carving is in process. Usually after several passes the Z height return to the proper level. This could happen again - maybe, maybe not. This occurs when flattening, stock removal, or during a 3D carve (2 images attached).
2 images - one is a large view and you can see this occurred
I also run Vectric to Carbide Motion. I have found that it is best to run a finishing pass at a 45 degree angle to the grain, especially in stringy woods (my favorite stringy wood is cypress). The fibers do not sever cleanly causing a “grab” on your cutter. Running with the grain in stringy wood doesn’t shear the fibers, it peels them.
This can be caused by poor wire harness connector contacts. I’ve had issues with my Z & X axis doing that sort of thing - just a couple lost steps here or there that doesn’t seem to really affect the final outcome much.
I found what finally got rid of it was changing out the connectors to something more robust that maintains good contact even while the gantry gets vibrated while moving fast. I actually think one of the pins on my Z-axis motor connector showed discoloration due to being heated from contact resistance - which means less power getting to the stepper motor to move it & maintain accurate & precise positioning & movement.
Thank you for the responses. I check all wiring & harnesses for any discoloration or signs of heated conditions, tightened every last bolt, screw, etc… and did a full maintenance of the machine. I then ran a test and got ZERO changes in height. I will watch and see if this occurs again and maybe I can narrow down the ultimate issue.
Please note that poor connector connections do not always give a visible indicator. The connectors are susceptible to vibrations during machine use & different vibrations can cause sudden intermittent loss of steps in a connector that is just barely making proper contacts. You can easily check your stepper motor connectors for issue by simply jogging an axis & then fiddling/gently flexing/stressing the connector a bit while it’s in motion. If the stepper stops/grinds/reverses from just slight stress on the connector, then it’s most likely causing lost steps during operations when vibrations or a dust colleciton hose hits it. Some users have found that zip-tieing the 2-sides of the connector together works. But securing the connectors in positions that protects them from being strained in any way during operation is adviseable.
Folks -
I believe I found the problem. The placement of my dust hose! During a carve, I watch the dust hose follow insync with the spindle, not touching or interfering. Twice the hose appeared to cause a slight drag to the Z axis. When all was finished, that was where 2 inconsistencies were on the flay bottom. I removed the hose and left the Sweepy - perfect!! Ran 2 more jobs - perfect!!
Now to figure our a new, improved vacuum hose plan.
