Rostock Tower Calibration Woes

[TimMcBrayer]

I have recently completed the mechanical build of my Rostock Max V2 and am working my way through the calibration process. I've got everything wired up properly and am working off of the User Guide 1st edition, in section 2.4. I have two issues.

The first issue is annoying, but I can deal with it. It is an issue with running the "Tower Cal" gcode script, which moves the hot end sequentially towards the X, Y, and Z towers so that the height of the extruder can be adjusted. Usually, it stops early and doesn't complete the program. Most common it seems as if the script simply quits during or after the programmed pause with the extruder by the Y tower. If it proceeds from there it will then sometimes stop by the Z tower. Only occasionally will it finish the program and return to the center after visiting all three axes. I've retyped the script, and tried copying it from the PDF, with no change in behavior. It always fails to resume from one of the pauses (G4 S5). But the first two pauses always complete successfully.

The second and more troubling issue is that the adjustment procedure and end stop screws just don't have the range of travel to complete the calibration. I have the X and Z screws bedded down as short as they can go, and the Y screw fully extended, and the extruder is still way too high at the Y tower calibration point. I'd guess it's around 1mm too high, with no threads left to extend. A longer screw seems like a possibility, but it also feels like it would be masking the real problem.

I've checked that the end stop switches are securely mounted, and that nothing is interfering with them. The belts are all of equal tightness, as far as I can tell, and none of them are slipping that I can hear. It's acting as if the Y tower is too tall, if I had to hazard a guess.

Do I start disassembling the printer to ensure the Y tower is seated fully at top and bottom? Is this sort of issue adjustable in the software? Any ideas on what my next step should be?

[IMBoring25]

It does sound like a problem with tower seating, lean, or twist. There is the ability to do a software offset for the endstop locations, but if you're that far off, I'd expect you'll have significant dimensional issues with your prints.

[TimMcBrayer]

Thanks for the confirmation. I definitely didn't get the top of the printer seated on the Y axis!

Oops...

[geneb]

That same thing bit me once.

g.