Recommendations for FARO Arms

This page answers questions about which FARO arm to use in your tube measuring application. We've listed the different options in this page so that you know what to consider.

Arm Repeatability and Ball Probe Accuracy

This chart shows the arm repeatability for the different FARO arm models. FARO arm sizes is listed in VOLUME - which means the diameter of the sphere volume that the arm can reach in total. So the length of the arm 1/2 the volume value.

	WORKING VOLUME
	1.2 M (4 foot)	1.8 M (6 foot)	2.4 M (8 foot)	2.7 M (9 foot)	3 M (10 foot)	3.7 M (12 foot)
Edge		0.024 (0.0009)		0.029 (0.001)		0.064 (0.0025)
Prime	0.016 (0.0006)	0.019 (0.00075)	0.024 (0.0009)		0.042 (0.0017)	0.060 (0.0023)
Fusion		0.036 (0.0014)	0.043 (0.0017)		0.074 (0.0029)	0.104 (0.0055)
	REPEATABILITY mm (in) Performance specifications according to B89.4.22

These repeatability values are also referred to by FARO account managers as "accuracy" values. You can expect the ball probes to perform within these values when the arm is setup and used properly.

In general, you can take these values are double them to get the expected accuracy of the laser scanners. FARO also calls these "Laser Line Probes" because they scan using one line or "stripe" of laser at a time. The different scanners have a huge variance in performance. Choosing the right scanner is very important. (More important than choosing the right arm in our opinion.)