does slic3r account for extrusion width in holes?

No matter how small I trim my external perimeter extrusion-width down, I can't get a 2mm hole to actually be 2mm. It seems like Slic3r puts outer perimeters exactly at the hole dimension then the external extrusion squishes out further. I don't want to have to oversize my holes in the design...

mini kossel with 3mm PLA, 205 deg, bed 40 deg on blue tape, 40mm/sec perimeter, 90% width small perimenters @ 20mm/sec
thanks

I'm pretty sure Slic3r accounts for that. There's probably a setting that'll adjust it as well, make sure it's on "expert mode."

This is a very common problem and I am not aware of any complete fix or workaround other than to oversize holes that are aligned with the Z axis. Checking 'external perimeters first' reduces the extent of the problem in my experience.

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Large delta printer [miscsolutions.wordpress.com], E3D tool changer, Robotdigg SCARA printer, Crane Quad and Ormerod

Disclosure: I design Duet electronics and work on RepRapFirmware, [duet3d.com].

There are many effects at play that affects hole size. Filament tends to be drawn inward when cornering, the matetial shrinks when cooled, the inside of the corner is squashed more than the outside etc. If layers aren't perfectly alligned, it makes the hole smaller. You can try hexagonal holes instead of circular, which helps. Drilling out holes isn't that bad.

See
http://manual.slic3r.org/troubleshooting/dimension-errors

The only fix is to download and print a hole size chart on Thingiverse and then design your holes based on that chart. Here is the one I designed [www.thingiverse.com]

I probably have used it 500 times since I designed it.

Slic3r has a setting in the advanced tab of print settings that can compensate for wrong hole sizing; maybe you could adjust that value to fine tune hole sizes.

How does that XY size compensation not change the dimensions of everything?