'Bad' Accuracy of finished parts

I don’t know weather to put this is the hardware or software section.

I have a pretty new Taz 6 that I really love overall. However, my finished parts have sloppy tolerances. If I draw a part say 2 millimeters thick it can come out anywhere up to 2.29 mm thick. If I draw a slot 2.2 mm wide to accept the 2 mm part it could come out as narrow as 1.5 mm. Sometimes it comes out right but 90% of the time I need to trim and cut every part and slot. It gets very frustratrating.

I am using Verbatim PLA and the built in settings in Cura. I never use the “speed” setting and the difference (as regards this problem) between standard and high detail is marginal. if I use “high detail” I may not have to trim by hand as often but I still have to trim most of the time.

So am I expecting too much? Is .5 mm tolerances to much to ask? Is this the machine or Cura?

Perhaps I need to totally rethink my designs but I have had the same problem with every interlocking method I have tried

This and variations of it are are what I am trying to do.

It sounds like you’re using the default settings. If you want parts that are very accurate, you need to calibrate the printer. There are a lot of threads around the forum, but I’d start with these to see if you get closer. Note you will need the expert settings in Cura.

Filament diameter. Measure this with calipers/micrometer and enter it in Cura. Every filament is a little different.
Extruder idler tension. Set it so there is about 5mm between the washers to start with.
Extruder E-steps.
Z-offset. Make sure the first layer is exactly the height you asked for.
First layer extrusion amount, this is set high by default. Dial it back to 100%.

Start with known calibration parts like the simple 20mm cubes. Make one change, test, repeat until you get that setting dialed in. And note you might have to adjust temperature etc. when you change colors etc… Usually not a lot, but it’s good to know.

Excellent! Thank you for the useful reply!

I had searched on “accuracy” but did not get anything useful. “Calibration” does sound like a better search term! Duh! :slight_smile:


Dont forget to adjust your extrusion multiplier also, I typically use 95% for fairly good fit.

Is that a Cura setting? I don’t recognize that one (I am not in front of the software right now)

For anyone else reading this… I found Z-offsets in the manual but the esteps @ttabbal mentions were less obvious

So I got a couple of great links from Nick Prust at the help desk support on setting esteps and other calibration tasks.


Plus there are several other great step by step guides under.

Yeah, OK, I am simple, I like step-by-step guides with big pictures, I can admit it! :slight_smile:

Hey guys,

I did not want to do thread about filament here in the hardware forum so I started a new one in the appropriate place. I think I have problems though? Or do I ? :slight_smile: https://forum.lulzbot.com/t/filament-tolerances/4318/1

I did everything you said and I am getting straight up 20 mm cubes now (except as noted in the other thread, filament variations) but I think I have the base machine set up well now!

Thank you and everyone else for chiming in and edu-ma-kating me!


robajohn thanks for posting the links you got from support. I was just about to put up a post looking for help with some minor issues just printing a 25x25mm cube to tighten up my prints and saw your post. Running to my printer right now with a black Sharpe to work on my Esteps. Fingers crossed!

So glad I found this post. I will probably do this first when I get the printer setup tomorrow. :slight_smile:

In cura “extrusion multiplier” is known as Flow(%).

Thanks Jim!