Accuracy issue

Hello all, long time follower, first post.
I have created an i3 modeled printer with a 12"x12" printbed. All works great with one exception. I create models in autoCAD units in mm, I use Repetier units set in mm. I created something that needs close tolerances a couple days ago and noted pieces were not exact. So I created a 20mm cube with 1mm walls. Off the bed I pulled a 19.89mm cube with 1.13mm walls.
Setup: ramps 1.4, Repetier, slic3r, E3d hotend, .4 nozzle.
I need my resolution tighter, any knowledgable peeps out there that may be able to help?



Thanks,
B

You are probably extruding to much material. Check your nozzle size, calibrate your extruded and if that does not work, play with the filament multiplier setting in your slicing program.

Calibration links can be found in this thread:

hotend issues
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