MakerFarm 8" i3v Prusa build by Printbus

[printbus]

NOV 2014 BENCHMARKS USING MAKE:2015 TEST MODELS - continued

Results for the Dimensional Accuracy, Overhang Performance, Fine Positive Space Features Performance, and Mechanical Resonance in XY were discussed in the prior post.

MECHANICAL RESONANCE IN Z
My initial round in ABS didn't fare well, possibly because as the column got taller, I could see the print moving as the nozzle moved around each layer. The final PLA print didn't have that problem and came out very clean throughout the entire column, with no discernible difference between the bottom and top of the column. This was also printed without a minimum layer time constraint, with cooling airflow applied, and zero infill to eliminate bits of infill that analysis in gcode.ws indicated would appear between the inner and outer walls. Scores a 2 out of 2.



NEGATIVE SPACE TOLERANCES
On the initial ABS print, I could remove three of the pins. On the subsequent PLA print, I could only remove two. Work remains to figure out whether this can be improved through Cura settings. This only scores 2 out of 5.

FOLLOWUP COMMENT: With Slic3r, I obtained a print with one additional peg loose. With Simplify3D, the print had four of the five pins removable.



BRIDGING PERFORMANCE
This model surprised me in both the ABS and PLA prints. I expected very poor results since Cura provides no settings specific to bridging. While there a couple of droopy ones, all spans are intact. The drooping exceeds 2mm, so this gets a 4 out of 5. Not bad for a slicer that most view as incapable of bridging. This model was printed with a brim to ensure bed adhesion. A hefty amount of print cooling airflow was applied, with the print oriented so that the airflow was in-line with the spans.



RESULTS SUMMARY
My assessment of the final prints totals to 24 points out of a possible 29. The biggest hit is the loss of three points since only two pins could be removed in the Negative Space Tolerance test. Not messing around with eliminating the fine strands left on the Fine Positive Space Features Performance test cost a point. And I'm very happy with only losing one point in the Bridging Performance test.

Note that you can't directly compare these totals to the results in the Make: Shoot Out article. Inexplicably, the article uses a different scoring structure than provided in the Thingiverse instructions for the test models. I also wish that Make: would have provided photographs of some of the scoring results in order to improve consistency in the assessment results.