Calibration Problem

[jmargush]

I just recently got a Rostock Max v2, I went to go print my fan shrouds and I noticed that the fan was very loose in the peek fan shroud but didn't think anything of it until my layer fan was too loose in it's shroud.

I didn't touch any of the scaling settings I then measured the shroud and it was about millimeter off.

I then printed a calibration cube from MatterControl and these are the measurements, 21.2mm X-axis, 21.5mm Y-axis, and 10.07mm Z-axis. My Z-axis seemed to be printing properly.
I then used the Prusa calculator to find my steps per millimeter and got 80 I went into my EEProm ready to change it when I noticed it was already set to 80.

Next, I printed a 5 mm cube and that was sloppy so I decided to print a cylinder that was 30 mm wide and that was 31.87 mm.

I believe it might be over extrusion from my extruder motor or something else that I don't know about. I would really like to know how to get my prints to come out with proper dimensions. Any ideas or fixes I could try? Thanks.

[Eaglezsoar]

Check your configuration.h and find the entry for diagonal rod length, for a standard Rostock Max 1 or 2 the entry should be 269.
See this link: http://forum.seemecnc.com/viewtopic.php?f=60&t=7826

Ensure your belts are snug on all axis. If none of this works just post another message in this thread.

[jmargush]

The Diagonal length is 269, and all of my belts are snug.

[Tincho85]

Hi, do you have the new ball-cup arms?
If you do and your arm length is set to 269, your prints will be bigger. Because your printer thinks it has to move further than it actually does.

The diagonal rod length for the ball-cup arms is 290.8mm.

[Eaglezsoar]

Hi, do you have the new ball-cup arms?
If you do and your arm length is set to 269, your prints will be bigger. Because your printer thinks it has to move further than it actually does.

The diagonal rod length for the ball-cup arms is 290.8mm.

Good Catch! I had forgotten about those arms.

[jmargush]

Hi, do you have the new ball-cup arms?
If you do and your arm length is set to 269, your prints will be bigger. Because your printer thinks it has to move further than it actually does.

The diagonal rod length for the ball-cup arms is 290.8mm.

I did what you said and it printed too small so I fiddled with my arm length and now I have it set to 281.2 mm.

Is this okay to change or is there another setting that I could change to fix my problem?

I also noticed that my X-axis was printing about .11 mm off. Is that a big difference or is that a good tolerance?