If you are looking for perfect circles and all else is calibrated focus on the y-axis drive rod.  Been covered many times, search for the "how to print perfect circles" post by user Adrian.  To give you an idea of some options.

Link: http://www.soliforum.com/topic/4824/how … -for-ever/

Looks like I am reviving an old topic here, but would like to know if Raven or Gomisan was able to eliminate the .5mm dimensional size issue using the nickle calibration? I am only able to get either the inside or outside of the calibration to be accurate with the x y steps. If the inside is perfect, the outside is too large. The suggested solution of dialing down the extrusion multiplier isn't good, because I would be going below 90%. The e-steps are well calibrated to begin with as well.

Also, even with much adjusting/ aligning /lubricating the belts and pulleys, stepper voltages, acceleration and jerk setting, as well as eliminating looseness in the print head, circles print out of round- diagonal to the x y! I would appreciate knowing if anyone else had these problems when calibrating the x y with a solidoodle 2.

Thanks for all the help everyone has provided already - I learn so much from this community!

Ok... thanks I'll check that. That's exactly the wall width I got doing a single walled cube. But I'll try measuring the raw extruded material.

Don't confuse a printed wall with an extruder into thin air using the manual tab extrusion... One is volumetrically controlled to deliver the wall width specified in the slic3r config and the other is just dumping filament out the nozzle and allowing it to naturally expand as it cools...

i.e, you can make a .4 nozzle print .42 or .48 or even .6 walls...

At the end of the day - I think you'll be just chasing your tail.. its pretty much a certain that any printer shipped since May has a .4mm nozzle - thats all they stock now. You'd be far easier just using calipers to measure the nozzle hole than guessing based on the expansion of an extruded thread... But either way... its highly unlikely you have anything other than a .4mm nozzle given when you ordered your printer and since you have a printrboard... Feel free to Skype Solidoodle or ask on the IRC Channel.. but you'll most likely get the same advice as above directly from Solidoodle too...

Anyway, all I can do is do each calibration and eventually I'll hit upon the one that is affecting it.

Also.. on the Solidoodle site is says:

http://store.solidoodle.com/index.php?r … duct_id=79

So where does it say they use a .40mm nozzle?

If you have gaps - then check both your extruder steps-per-mm and your extrusion multiplier .. bump it up .01 or .02 and see how it goes.. or use the Flowrate % indicator mid-print to see... again only 1% or 2% should be required (i.e, 101, 102...)

maybe i should measure my extrusion rate... with longer length.. I only measured 3cm.. maybe i should try the whole 10cm so this way the error rate is smaller.
I guess I will also check my Z... by printing out a cube to measure height and check my wall width and such.. maybe after all these... I will accept my defeat :-)