Y Gantry lags behind B Gantry

I have a Woodworker X50 with Masso.I recently was getting a B rail error message with homing. Support told me to update to the latest firmware, which I did, and then I got a Y rail hard limit warning with homing. The Y gantry would go to the limit switch on homing and stick there, actually moving forward a little bit while the B rail did what it was supposed to do, getting to the switch and moving back a couple of mm. Support told me to remove the X rail and then run the Y and B gantries back and forth as fast as possible. At first, the Y gantry did not move, but after I cycled it backwards and forwards several times, they seemed to move together. I replaced the X rail, and now it would home and there would be no error. I then ran a job which came out very rough and uneven using a 1/16th tapered ball nose, which has never happened before.

When I started moving the gantries around, I would notice the Y gantry would lag behind the B gantry slightly when moving forward and backwards at higher speeds. When I would move them all the way to the back, they would both strike the back of the rails. When I move them all the way forward, the Y gantry would be about three-quarters of an inch shy of the limit switch while the B gantry was appropriately at the limit switch. I shut it off and re-homed a couple of times, and it would re-home perfectly with both gantries hitting the limit switch. The same thing would happen as I started moving the Y and B rails back and forth. The Y rail would lag behind, and there’d be a gap when I brought it all the way forward. The pictures below show the gantries at maximum forward position after homing. I also included a picture of the machine settings, where the estop shows “High” as does Input 7. Don’t know if those have anything to do with this or not.

Have you tried turning off the controller and pulling the Gantry as far back as you can on both sides then re-homing? Also make sure your rails and ball screws are properly lubed.

I just did it and the Y gantry lags on the way up. It gets to the limit switch just after the B rail and homes with no warnings, but it is lagging behind the B gantry whenever I send it backwards or forwards still.

Kurt Ehlert

Check all your cables and make sure all your connections are good, maybe even unplug and re plug them in on both ends. If that doesn’t fix it check for mechanical binding. Unbolt your stepper motors and “move” the gantry and see if both steppers are spinning. If they are, then leave them off the machine and push the gantry back and forth, see if you feel any major resistance. If you do, then I would unbolt the ball nuts, and push the gantry back and forth it should be smooth, if it’s not then you could have a bad linear bearing. If it’s smooth, spin the ball nut on the ball screw, it should be smooth. If not then you probably have a bad ball nut.

I am new to the Onefinity machines, and I am waiting for my new machine from Onefinity, but I do have another brand, so my thoughts may not work. If you can swap stepper motors and see if the problem follows the motor or if it stays consistent with the change. On my machine, I can swap the stepper motors left to right without any problems, which I have done for testing. Just a thought.

Randy

I just took the ball nuts off every axis yesterday and cleaned them.

Kurt Ehlert

Are both steppers spinning/functional?

With the Xrail off, the Y rail catches compared to the B rail. When I removed the motor, the gantry moved smoothly again. I took off the bushing and replaced it and the gantry moved smoothly but as soon as I put the motor back on, it started catching again.

Try taking your Y motor and swapping it with the side of the gantry that seems to be lagging behind. If that solves your problem then you have a bad stepper. If that doesn’t help then try swapping your Y cable with the B output on your controller. The idea is to isolate if you have a bad stepper or a bad controller channel.

Im having the same problem with machine with the QCW and the fixed stand. After measuring diagonal to measure for square i was about .6" off. If i was on a wood bed like you i would loosen up you top gantry then remove your Y1 bolts and move it to the correct spot making sure your diagonal measurement proves your square redo the alignment procedure redo. Good luck

When I switched the Y rail stepper to the B rail, now the B rail stutters and doesn’t move smoothly without power.. It seems the original Y rail stepper is the problem. I’m assuming I need to replace that stepper motor, right?
Thanks for all your help, by the way.
Kurt

Yes probably the stepper. If all you did was swap the steppers. If you swapped the wires at the control box then it is probably the driver if you are on an open loop system. Does that make sense? Glad to help.