nickel calibration print undersized

[bretsquire]

So after updating the firmware and doing the Z axis and tower calibrations on my Orion printer everything seems to be working great except that it fails the nickel calibration test: http://www.thingiverse.com/thing:11261

I don't know if this has to do with the printer or how slicer is configured but the hole is slightly smaller than a nickel.

Is there any configuration settings I can tweak to improve this?

[Polygonhell]

How much undersized, it's not actually a very good calibration piece, because circles tend to shrink.
It could be any number of issues from over extruding, to the slicer putting a slight seam in the circle, to an actual physical calibration issue.
If you really want to calibrate for size, do a real extrusion width calibration i.e. print a single wall test cube, and verify wall measured wall thickness against specified wall thickness (note if your using slic3r and not overriding it, you need to look in the comments at the top of the gcode for this). Once you've done that print a 100x50x10 rectangle and measure it. Usually they are slightly undersized because of plastic shrinkage.

[1ggy]

If you're printing in ABS, you should see a shrinkage of just under 1% from the physical shrinkage of the material as it cools. To fix this, you have to use the scale feature in the slicer. The problem with circles, however, is that when you make them, there is going to be more material on the inside of the circle than there needs to be. Skeinforge has a feature that can account for this and allows accurate holes, IDK about cura or slic3r though.

[bretsquire]

@Polygonhell
For a 100x50x10 test:

• is that x,y,z planes respectively?
• is that the same as the previously mentioned single wall test cube?
• what am I looking for in the comments of the gcode?

@1ggy
Is Skeinforge easy to setup for the Orion printer or should I just stick to slic3r?

[Polygonhell]

There is a sticky somewhere on extruder calibration that describes using the single wall test print.
The 100x50x10 is x, y, z it just needs to be long enough to minimize error in measurement.