There's no single answer to what measurement tool I should buy. It depends on what you're measuring, how tight the tolerance is, and what it costs if the measurement is wrong. I say that as a procurement manager at a 180-person aerospace supplier. I've managed our metrology equipment budget of about $180,000 a year for six years, negotiated with more than 40 vendors, and logged every order in our cost tracking system. When someone asks me about FARO laser tracker accuracy, my first question back is: accuracy for what?
Here is the way I sort measurement requests. I separate them into four buckets:
- Large 3D parts and assemblies
- Small one-axis depth and step features
- Electrical signals and power issues
- Thermal patterns and temperature anomalies
Your team may have all four. That's normal. The mistake is assuming one tool can cover all of them.
Four scenarios I use when choosing a measuring tool
Before comparing spec sheets, define the job. Are you checking a one-inch step? A whole assembly frame? A voltage signal? A hot spot on a motor? Each one leads to a different tool. In our own purchasing history, the most expensive errors came from starting with an impressive catalog and then trying to make it fit every task. That gets expensive fast.
Scenario 1: Large 3D volumes -> FARO laser tracker
If you need to measure a large part over multiple axes—an aircraft jig, a car body side, a turbine housing, a whole machine tool alignment—a FARO laser tracker is genuinely hard to beat. It gives you 3D coordinates across a large volume, sets up in different locations, and can track a target as you move around the measurement envelope.
FARO laser tracker accuracy is usually published in micrometres per metre, but I don't rely on that number alone. The meaningful figure depends on the test standard. Look for verification against ASME B89.4.22 or ISO 10360-10, which define how the accuracy test is run. What I mean is that the published spec is measured in controlled conditions; your shop's temperature gradients, floor vibration, operator skill, and even the lighting can change the real-world result. A tracker is not a plug-and-play device.
There is also the FARO app. I used to treat software as an afterthought, but the companion app changes how fast your people can set up a measurement plan, collect data, and interpret deviations. During our 2024 audit, we found that our lead technician's familiarity with the FARO app cut setup time by about 30% compared with the previous year. That is a soft saving, but it shows up in inspection throughput.
From a cost view, the purchase price is only the beginning. A laser tracker needs calibration every year or two, depending on use, plus a service contract if you want priority support. Shipping the unit back to a service centre and losing it for a week has a real cost. In Q2 2024, we paid $400 for a rush calibration slot on our tracker because the standard queue would have put us past a customer milestone. That felt like an upcharge, but the alternative was missing a $15,000 delivery window. The question is not whether the $400 is fair. The question is whether the certainty is worth more than the risk.
Scenario 2: Small depth and step checks -> digital depth micrometer
Now the opposite situation. If you're measuring a slot depth, a counterbore step, or a ledge that is under 50 mm, a digital depth micrometer is usually the better tool. It has high resolution, it is calibrated in seconds, it costs a few hundred dollars, and it can sit right at the work cell.
When I audited our 2023 spending, I found that 70% of our dimensional checks were on small features where a digital depth micrometer was accurate enough. We still had portable CMM arms and a far more expensive system on the floor. The arms are great for certain tasks, but for a one-axis depth check, they are overkill. The cheap tool is often the right tool. I know that goes against the impulse to buy the flagship system first, but the total cost of ownership is way more important than the sticker price.
Should you buy a FARO tracker for this scenario? No. You'd be paying for 3D capabilities you don't use, and the extra training and setup time would slow you down. Get a good depth micrometer, keep it calibrated with gauge blocks, and teach your machinists to use it. It will solve more daily problems than a laser tracker will.
Scenario 3: Quick electrical checks -> keep a multimeter nearby
Some measurement problems are electrical, not dimensional. A sensor starts drifting, a probe loses power, a connection corrodes. If you don't have a multimeter nearby, you will waste time hunting for a dimensional problem that isn't there.
I learned this back in 2020 during a phantom quality issue. Parts looked slightly misaligned, and we spent almost two days rechecking the fixture with a CMM arm. It turned out the power supply to the probe had a voltage drop, which made the feedback signal unstable. A $90 multimeter found the problem in about ten minutes. Since then, every machining cell in our area has a multimeter nearby, and we've cut a ton of wasted troubleshooting time.
This scenario is a reminder that your measurement toolkit should match the failure modes you actually see. For electrical checks, a multimeter is faster, cheaper, and more appropriate than any optical metrology system.
Scenario 4: Thermal inspection and the glass question: can thermal cameras see through glass?
Thermal cameras are useful for finding hot motor bearings, overloaded circuit panels, and missing insulation. But the most common question I get is whether a thermal camera can see through glass. It can't. Glass reflects long-wave infrared and blocks almost all of the IR signal from the other side. So if you point a thermal camera at a window, you see the reflected thermal image of your own surroundings, not the temperature behind the glass.
This applies to FLIR models as much as any other brand. FLIR makes excellent thermal cameras, but they are bound by the same physics. I once had a manager ask us to buy a thermal camera to scan a product behind a glass inspection door. We didn't need a new camera; we needed a hatch that let the IR through, or a contact sensor on the product itself. The camera would have been a $3,000 mistake.
If you need to inspect heat from a target behind glass, get a germanium IR window or use a different measurement method. If the target is not behind glass, a thermal camera can be a valuable addition to your inspection toolkit.
How to tell which scenario you're in
When a request comes in, I ask three quick questions:
- What exactly are we measuring? A 3D coordinate, a single depth, a voltage, or a temperature pattern?
- What will happen if the measurement is wrong by more than the allowable tolerance? A rework, a customer rejection, or a safety issue?
- When does the answer need to be ready? If the deadline is tight, the reliability of the delivery schedule matters as much as the tool's accuracy.
That last point is the one I keep coming back to. A low-cost tool that arrives too late can cost you more than a premium tool that arrives on time. In 2022, we rented a cheaper measurement option for a rush project and it failed on a 0.05 mm tolerance. We had to redo the whole setup and lost a weekend. The rental was $1,200; the redo cost us about $8,400 in overtime and schedule slips. We never made that trade again.
This is also why I have mixed feelings about rush fees. Part of me thinks they are overpriced. Another part of me understands that the vendor is selling priority access to a finite resource, especially when calibration and service capacity are tight. After the 2024 tracker calibration incident, we now budget a small line item for rush service every year. We hope not to use it, but it removes the surprise from the decision.
One more thing: do not expect any instrument, including a FARO laser tracker, to stay accurate without regular calibration. If a supplier implies otherwise, walk away. Calibration is not an optional fee; it is the input that keeps your accuracy claims valid.
Bottom line on FARO laser tracker accuracy and your budget
FARO laser trackers are excellent for large-volume 3D measurement. If that is your main requirement, they deserve a place in your capital plan. But they are not the answer to every measurement need. A digital depth micrometer handles small one-axis checks, a multimeter nearby handles electrical problems, and a thermal camera handles temperature patterns—as long as there is no glass in the path.
Build your spending plan around the measurement tasks you actually perform, not around the most advanced spec sheet. Compute the total cost of ownership, including calibration, software, training, and rush service. And when a deadline is tight, pay for certainty: the expensive tool that arrives on time is usually cheaper than the affordable one that does not.
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