Trouble printing perpendicular walls I'm trying to print the following model:


I'm using Simplify3d to print the model with the following settings on my Qidi X-pro:

Filament is ABS
Bed temp is 100 °C
Extruder temp is 230 °C
1 top layer
1 bottom layer
4 perimeter shells
The outside direction is 'outside in'.
Internal infill is triangular at 60 %.

I've tried numerous tweaks to the settings, but, I can't seem to get a perfect perpendicular exterior wall as seen in the photos. The print more resembles a trapezoid. It appears like the walls are bowing inward. This also seems to throw off the dimensions. They aren't consistent. For example, the height of the part is 6 mm, but, in measuring with a caliper it shows 5.8 mm to 6.2 mm.
Can anyone tell me how I can get my external walls perpendicular?
You may be getting shrinking due to cooling on the non-top and non-bottom layers. Sixty percent infill is rather substantial. I'm printing 20 hour pieces in ABS at 100 °C / 250 °C using ten percent infill and getting nothing like what your image shows.
Can you do with a lower infill? More isn't always stronger. Four perimeter shells may be a factor but you'll probably see a difference with a smaller percentage infill.