First I have to tell you how much I am loving my X-Carve. I started out with the MPCNC and moved to X-Carve when my MPCNC gave me soo much trouble that I retired it.
The X-Carve has been so much more reliable and generally trouble free.
Unfortunately it has not been completely without issue. Last week I had an 1/8" mill chucked up and started a carve. I set the Z probe up for zero and it failed to stop when the mill hit the Z probe puck. It continued down, broke the mill and, in the process, forced the carriage towards the front of the machine. When this happened it moved the Y zero stop forward a bit over 1/4".
Now my zero is off. I need to move the Y zero stop back to it’s original position or re-mark my waste board to reflect the new zero. I prefer to return the previous zero.
I am a bit stumped as to how to do this. Any suggestions?
Also, any tips on preventing future Z crashes would be appreciated.
what program was you using to Z-Probe with? Easel or something different like UGS, Bcnc, Chillipeppr? if Easel did it make contact before sending the probe command? if not Easel how do you know that contact was made? that is why Easel has the check for contact before you send the probe feed down, if no contact is detected then don’t send the probe as it will not stop until it hits it limit which is usually far below the waste board.
I would check my wiring for loose connections as it would seem that you lost contact and never triggered the probe.
I am using Easel and it did pass the “contact” test then failed to detect contact with the puck when I continued.
I am now poising my hand over the kill switch when I zero.
I did measure and input the exact thickness of my puck but I missed the the max seek distance setting. That said, I am having trouble seeing how that will save me in the future unless I limit myself to a fixed material (workpiece) thickness. What am I missing?
And finally, Jeff: I can figure out moving the screw but, what is the “correct position”?
I “ballparked” it and I have it close enough for rough work but if I want precision I need to fix it… And, while typing this response, I got an idea! EVERYBODY DUCK!!
Moving it is easy. The challenge is trying to get it back as close to exactly where it was before.
What I wound up doing was:
Homed the machine
Dropped the Z down until the tip of a Vee bit was almost touching the waste board
Jogged the Y to the right a couple of inches
Checked the gap between the zero switch and the stop with feeler gauges.
Used feller gauge to adjust a couple thousandths
Zeroed again and repeated the above process until the tip of the Vee bit centered (almost…) on the Y0 registration mark.
Fortunately the broken bit was a $3 mill not one of my spendy ones.
I noticed that the connection to my z-probe is flaky. With the probe plugged in to the female jack, I can rotate the male probe plug within the jack and can feel the resistance to my rotating the plug change – at the point of least resistance the probe isn’t making contact properly and will fail the z-probe test. Fortunately Easel has you check this prior to probing and the flaky probe connection has yet to cause a Z axis crash. I should note that simply rotating the plug a bit (until it resists rotation) will restore connection. I’m probably going to switch to a different style probe plug or seek out parts made to a more exacting standard and replace the plug ends…
Well… there are no graphics and that is not how I do it.
There are lines that I scribed in the waste board along X0 and Y0. Where they meet is, obviously, X0,Y0. That is the point where I locate my workpiece zero. Then I home the machine and then set the Z axis using the probe.
I prefer the consistency that I get using the machine home. When I was running the MPCNC machine I did not have limit switches so I did “eyeball” the start location and found that I could not manage adequate repeatability or accuracy.