X/Y tolerences in Lulzbot Cura

How does one adjust X and Y tollerences in Lulzbot cura?

I’m kisslicer (which I don’t have profiles for my Taz 6) I would simply set the inset. I see no equivalent setting in cura.

I have seen people suggest designing tolerances in to the part but that assumes two things;

  1. That the user always has that fine grain control
  2. That such a suggestion is reasonable even when they do.

Parts are designed to depict their intended output. Tolerances are decided in both the CAM and the CNC stages of fabrication, why would 3d printing be any different?

From a software standpoint this is an easy fix. Why hasn’t it been implimented? Parts are always going to be oversized unless there is a compensation.

I don’t think “tolerance” is the correct term here. Tolerance really is a function of the machine hardware (usually, and in this case), not software.

However, I do understand your problem. You say parts are always going to be oversized, but it’s actually generally the opposite. Since the material is hot when it extrudes, as it cools down it shrinks a little bit. This is usually only noticeable in the X/Y directions and results in undersized outer dimensions and holes. I think I read that Cura automatically compensates for this a little bit, but it is not adjustable as far as I know. One solution is to scale the part up in the X/Y directions just a bit: 1% or less.

On Lulzbot printers, the profiles typically squish the first layer down for good bed adhesion. This causes the outer dimensions of parts to be too big, and holes to be too small, on the bottom of the part. You can play around with your first layer settings (mostly Z-offset and initial layer height) to help fix this problem.

Personally, when designing a part, I always have the manufacturing method in mind beforehand. If I know I am going to be 3D printing a part on my Lulzbot, I throw a 0.02" chamfer on the bottom of my part to compensate for the first layer squishing. As far as the plastic shrinking due to cooling, this really isn’t a very noticeable problem that I worry about often.

CheeseJam, I think you mean (mostly Z-offset and initial layer height)

Yeah! Sorry for the typo, I fixed it.

You can calibrate the steps and change the firmware quite easily.