Prints too large in X/Y Replicator 2

Hey!

I am having a little trouble getting prints to be dimensionally accurate with my replicator 2. I have moved to slic3r as makerware is failing to slicing some complicated parts correctly, and I am having much more luck with slic3r. The one snag is that the prints are not coming out dimensionally accurate on the X/Y plane.

I am starting with a simple 20x20mm cube but the dimensions are 21.22, rather than the 20.15 when sliced with makerware. I am using whpthomas' slic3r configs found here and makerbot firmware 7.5.

I checked the Gcode from both makerware and slic3r with gcode viewer and it shows the same model size for each output. This I would have thought would indicate that the X/Y steps were set correctly in slic3r, but I could be wrong.

Does anyone know what the problem could be, or could point to a more detailed guide on using slic3r with a replicator 2?

Cheers

Jimbles

edit: Sorry, forgot to say I am using slic3r 1.2.0 on win7 64bit

Edited 1 time(s). Last edit at 08/19/2014 05:32AM by jimbles.

Slic3r does not deal in steps, the g-codes send the move distances in mm. The number of steps per mm are set up in the printer's controller (usually in a configuration file), not the slicing software. Over 1mm of oversize over 20mm is a huge error, if you are certain that your STL file is correct, it is possibly due to loose belts or some other mechanical problem.

Dave