Axis Fails to remain at intended Z Height

[Canadian Fenix]

Hello everyone,

I'm fairly new at this but I have tried my best to solve this issue by reading many forums so at last I am here.

I have a Rostock Max V2 and I'm using matter controller, I had tightened my belts and checked all my pullies about 30 hours ago and rechecked them when this issue presented itself, my belts are snug but not to tight, I can grab them fairly easily and they have deflection I feel is adequate for the installation. I've performed a visual inspection of the entire belt system and the attachment of the drive gears to all stepper motors and everything seems ok.

The Y axis is having trouble staying at the proper height when printing. I have checked and recheck Z height and Ensured proper bed levelling and it has not helped either.

After ensuring proper first layer height can be achieved at all axis I start my print and as the head approaches the Y axis the layer squishes excessivley, the longer it prints close to the Y axis the worse it gets and when the next layer starts its like the Y axis is left behind and the problem continues.

I have used functions in Matter Controller to test the height of the head from the bed after a failed print attempt and the head moves well from Center to Z , Center to X and then scrapes and drags itself from Center to Y.

If I have not provided enough infor for a diagnosis or if you believe you have an idea about where I should start looking I would appreciate any help that can be provided. Cheers.

[mhackney]

What happens center to -Y ?

[Canadian Fenix]

The head drags and scrapes the bed, if I'm using PLA with green tape it shreds the tape up and is possibly damaging the glass. No glass damage confirmed yet.

[mhackney]

So to be clear you get dragging in both center to positive Y and center to negative Y? But not along the Z and X both positive and negative directions?

[Canadian Fenix]

I've taken more time to observe the issue, this is what I noticed.

Using The tower calibration macro provided by seemecnc I observed the Center to Y axis movement. It's clear that "something slipped" as the head traveled I noticed a small but noticeable drop towards the bed while moving towards Y tower. When the tower calibration completes it is apparent the Z height had shifted closer to the bed than at the beginning. I ran and re ran the macro, as soon as the limit switches are pressed it restarts and does the same thing every time.

[IMBoring25]

If the belts stay properly tensioned it almost has to be the grub screw on the motor.

[KAS]

Are the limit switches mounted securely with no wiggle? Sometimes they'll loosen and give weird results.

[Canadian Fenix]

It was the grub screw, thanks. i discovered this upon pulling the motor.