'The University of Texas at Austin, Bureau of Economic Geology'
Abstract
12 identical FDM parts were produced in ABSM30, each having 16 features for replicated
measurements. Half the features were positive (posts), half were negative (holes). Half of all
features were rectangular, half were round. Two different CMMs with 1.5mm touch probes were
compared, one CMM additionally used a laser, and manual measurements were taken with
gauges and calipers. All features were measured using these 4 measurement systems. All
measurements were compared against the theoretical feature size to generate a percent error
value. The laser values were notably different than both probe values. The manual
measurements were similar to one of the two CMM probes. Positive versus negative features
were significantly different in 7 of 8 cases. Feature size and measurement error were inversely
proportional. The largest features had the least amount of error in all cases while the features
below 6mm had the most error and high variation.Mechanical Engineerin