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 scanners "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.)

FARO HD Scanner

The HD scanner is the blue laser scanner. It is also known as "Version 6" internally at FARO. It is, by far, the best performing laser scanner that FARO offers. If you can afford this scanner, then we strongly recommend it over every other scanner. The reason is because it handles reflectivity issues MUCH better than all previous versions. For details on why, see this page about the scanner: FARO Version 6 Scanner

FARO ES Scanner

The ES scanner is the last red laser scanner released. It is also known as "Version 5" internally at FARO. It's performance is much better than any previous versions, but (unlike the HD scanner) you may have to deal with lighting issues with this scanner. Sometimes external lighting can interfere with this scanner. You may need to move the arm to a darker room to measure. Skylights from external sunlight will make scanning impossible in our experience. It also cannot handle reflectivity issues as well as the HD scanner. The way to solve this issue is to spray the part with a surface coating that is a white or a bright color (yellow, blue, green, red, etc.). If you must purchase an non HD scanner, this the only other scanner that we recommend.

FARO Version 4 Scanner

This is the original Edge scanner. We only recommend it if this is your only option.