Dimension accuracy issues with S5

[davelnewton 0]

I'm vetting my newly-acquired S5 and having some serious accuracy issues.

 

I have a simple Lego cap (hollow rectangular prism with solid top), 8mm x 24mm external, 1.6mm walls. You know; Lego.

 

On my MakerGear M3 with its default settings I get a print in about 12m, and it's almost exactly 8mm x 24mm.

 

On the S5, *after* some deburring and sanding, it's 8.3mm x 24.2mm. Wall thickness is 1.7mm.

 

I'm running the stock AA 0.4 print core, still on the spool of 3mm filament that came with the printer. For comparison, the M3 is running 3.5mm.

 

Is this the kind of accuracy I can expect? 0.3mm is pretty far off (IMO, anyway; perhaps I've been spoiled). I'm trying a new print with a smaller layer height and less infill to compare, just in case, but it's already ~%30 slower than the M3. 

 

Let me know what else you'd like to know, I've attached the STL if anybody cares.

Lego 1x3 Spacer (Topless).stl

[AgelessRevision 0]

Have you solved the dimensional inaccuracy issue yet? I too am working on a UMS5 and facing similar issues in printing out standard small rectangular prisms. I'm using a 0.8 mm nozzle, printing  abs. The part I'm working with is a 35 mm x 12.0 mm x 4.2 mm block set at 100% infill, 0.7 line width and 0.8 mm layer heights. I found that tweaking the horizontal expansion setting can alter the accuracy of the x and y dimensions, but I have not found a solution for the z-axis yet. The dimensional inaccuracies i'm facing are 0.2 mm off in the z- dimension, and .35mm in the y.  

 

 

[Framar 38]

Same here. Working on a S5 and get a 0,2 to 0,3mm inaccuracy in X and Y.

[AgelessRevision 0]

What about in your Z dimension Framar? What do you think is causing your dimensional inaccuracies? I think faster print speed might contribute to inaccuracies in X and Y, i'm using 30 mm/s and get errors within the .2-.3 range.  Also, for me since i'm laying down 15 lines per layer at 0.8 mm line widths, I imagine the error is larger in that direction since the line widths i'm using are pretty fat.  Let me know if you solve your dimensional accuracies and what factors you changed if you don't mind sharing. 

 

 

FIX:

In my previous post I said I was printing 0.7 mm line widths and 0.8 mm layer heights, but I mixed up the numbers, I'm actually using 0.8 mm line widths and 0.7 mm layer heights. 

[MarcM 0]

@davelnewton - I'm not sure which material you printed with.  However, we also experienced accuracy issues and, in talking about it with our reseller, found that while Cura/Ultimaker adjusts print speed and nozzle temps for different materials, there is no accounting for thermal rate of expansion--apparently users are left to figure that out on their own.  We did some experimentation here and found that, for ABS, applying a scale factor of 1.0017 (X,Y, and Z) in Cura resolved the accuracy issues (mostly).