FARO Laser Tracker Rental and Precision Measurement: A Quality Inspector's FAQ

I'm a quality/compliance manager at a metrology equipment company. I review every technical document before it reaches customers—roughly 200 deliverables a year. In 2024, I rejected 14% of first-round deliveries due to calibration data or spec sheets that didn't match the actual product.

Here are the questions I actually get from engineers, QC leads, and purchasing teams.

• What is FARO and why does it keep showing up in measurement discussions?
• Is the FARO app actually useful?
• Is a FARO laser tracker rental a smart move?
• What accuracy spec should I care about on a FARO laser tracker?
• Laser tracker or portable CMM arm: which one do I need?
• Why should a QC person care about pipette stands and titrators?
• How to use Starrett angle finder correctly.

What is FARO and why does it keep showing up in measurement discussions?

FARO makes portable 3D measurement systems: 3D laser trackers, portable CMM arms, and the software that turns raw sensor data into inspection results. If a part fits on a traditional stationary CMM, you can measure it there. But if your part is a large weldment, a turbine blade, or a machine-tool frame, moving the part to the CMM is not practical. FARO's advantage is that the instrument goes to the part, not the other way around.

Everything I'd read about precision measurement said stationary CMMs were the gold standard. In practice, that belief broke down when customers started asking for in-situ measurements on parts that couldn't fit through the lab door. Over the past decade, the real trend is clear: traceable measurement is moving closer to the manufacturing line. That's not a knock on stationary CMMs. It's just that the measurement approach has to match the work envelope.

Is the FARO app actually useful?

In my experience, yes, but with limits. The FARO app is the companion app for field capture and device setup. It connects to a FARO tracker or arm, checks the device status, lets the operator preview measurement data, and sends it to CAM2 without manual data entry. On our shop floor, it cut a typical first-article setup from about 45 minutes to 20 minutes. (Should mention: the app does not plan your measurement strategy. You still need an inspector who understands datums and tolerances.) What I mean is the FARO app is an efficiency tool, not a substitute for experience.

From a quality standpoint, the efficiency gain matters because it reduces the number of transcription errors. Every time someone copies a coordinate from a screen to paper to a spreadsheet, there's a chance of a typo. The app shortens that chain. That aligns with what I tell every new hire: the best process is the one that removes manual steps without removing thought.

Is a FARO laser tracker rental a smart move?

Sometimes. A FARO laser tracker rental makes sense when you have a defined project, a clear schedule, and an operator who has run this equipment before. It works especially well for a two-week measurement campaign, a pre-purchase validation, or a sudden capacity spike. I had two hours to decide on a rental for a rush contract. Normally I'd do a full buy-versus-rent cost model, but there was no time. I went with the rental based on the project timeline alone. Even after I approved it, I kept second-guessing: what if the unit arrived without calibration? Didn't relax until the calibration certificate arrived with the tracker.

Inspect a rental as carefully as a purchase. Ask for the current calibration certificate, confirm that the certificate follows ISO 10360-10 for laser trackers, verify the software version, and make sure the operator has used that exact model before. The rental company's advertised turnaround means nothing if the data quality is bad.

What accuracy spec should I care about on a FARO laser tracker?

The number that matters is usually the maximum permissible error, or MPE, not a one-sigma marketing number. A one-sigma value is a statistical point on the distribution; MPE is a limit that the instrument should not exceed. Comparing one manufacturer's one-sigma number to another manufacturer's MPE is like comparing two thermometers with different scales.

I also look for the conditions behind the spec. Laser trackers can deliver excellent static accuracy under controlled temperature and stable mounting, but shop-floor performance depends on thermal gradients, vibration, and operator technique. This is why I ask for an acceptance test report performed to ISO 10360-10 before I trust a rental or a new unit. If the report doesn't state the standard, I send it back. It's the same rule I apply to every measurement device.

Laser tracker or portable CMM arm: which one do I need?

A FARO laser tracker tracks a handheld retro-reflector over distances from a few meters to tens of meters. It's the right choice for large parts, assembly jigs, robot bases, and machine-tool alignment. Because the tracker sends a laser to the reflector, you need a clear line of sight between the instrument and the measurement point.

A portable CMM arm is articulated and measures smaller volumes by touch. You can mount it to a surface plate or stand, then probe points directly on the part. It's better for dies, molds, and panels where all the features are within arm's reach. Laser trackers win for large-volume work—at least, that's been my experience with aircraft tooling and heavy equipment. But nobody should talk you into a tracker if all your critical features fit inside a two-meter cube. Size the equipment to the parts, not to the brochure.

A fixed CMM is still the right choice for small prismatic parts that need maximum rigidity and temperature-controlled repeatability. The portable system is not a replacement for that; it is a complement. In our lab, we use both. The portable arm handles inspection on the floor, and the fixed CMM handles tight tolerance measurements in a controlled environment. Efficiency comes from choosing the shortest measurement path that still meets the tolerance requirement.

Why should a QC person care about pipette stands and titrators?

On the surface, pipettes and titrators have nothing to do with laser trackers. In a quality system, they share the same principle: traceability. I've watched quality teams invest heavily in a portable measurement system and then trust a pipette that hasn't been verified in months. A tilted pipette stand can damage the pipette body or the tip; a damaged pipette gives wrong volumes; wrong volumes in your standards become wrong readings on high-end instruments.

A titrator, especially an automated one, needs routine calibration and a documented verification record. If the instrument that prepares your reference sample is out of tolerance, every downstream measurement is suspect. ISO 8655 covers piston-operated volumetric apparatus, and it's a good place to start if you're setting up a lab quality process. This is the less glamorous side of precision measurement, but it's often where measurement errors actually begin.

How to use Starrett angle finder correctly

If you're looking for how to use Starrett angle finder, here's the method I teach. It looks simpler than it is.

1. Clean the base and the blade. A tiny burr or chip changes the contact angle.
2. Release the lock, close the blade fully, and verify the reading against the zero mark. Do this every time, even if the tool hasn't moved from its drawer.
3. Place the base against one reference surface.
4. Rotate the blade until it contacts the surface you want to measure.
5. Lock the blade, then read the scale.

Like most beginners, I skipped the zero check once and adjusted a batch of brackets by the wrong angle. That mistake cost us a full rework day. Now the zero check is not negotiable.

One practical warning: for inside measurements, check which scale you're reading. The same tool can show the included angle or its supplement, depending on the reference edge. Put another way: if the reading is suddenly 180 degrees off, verify your reference before you adjust anything.