Choosing the Right Measurement Tool for Your Shop: Laser Tracker, CMM Arm, or Something Else?

Not Every Problem Needs a FARO Laser Tracker

When I took over purchasing in 2020, I figured there was one "best" measurement tool for our shop. I was wrong. After three years of ordering everything from FARO CMM arms to handheld multimeters, I've learned that the right choice depends entirely on what you're measuring, where you're measuring it, and how much downtime you can afford.

Here's the thing: no single device covers all needs. A laser tracker FARO sells is amazing for large-volume metrology, but it's overkill for checking a small bracket on the assembly line. And that cheap 10 multimeter from the supply closet? It'll get you a voltage reading, but don't expect sub-millimeter accuracy.

So let me walk you through the scenarios I see most often in our shop and what I've found works—and what doesn't.

Scenario A: Big Parts, Tight Tolerances, On-Site Work

If you're aligning a 10-meter press or checking the geometry of an assembled aircraft wing, you need a FARO laser tracker. Period. The portability and range (up to 80 meters) mean you can measure right where the part sits, without moving it to a temperature-controlled lab.

I had a near miss here. Two years ago, I almost approved a cheaper stationary CMM quote because the per-unit cost looked lower. But then I remembered the TCO lesson. The laser tracker eliminated the need to crane parts to a different building, saved 15 hours of setup per project, and reduced rework by 12% in the first six months. The $65,000 price tag? Painful upfront, but the payback was under 18 months.

What I'd tell a colleague: If your parts are larger than a washing machine and tolerances are ±0.001 inch or tighter, start with a laser tracker FARO. Don't let the sticker shock blind you to the savings in logistics and rework.

Scenario B: Medium-Sized Parts, Flexible Measurement on the Shop Floor

For the majority of our work—machined housings, brackets, fixtures—a FARO CMM arm is the sweet spot. It's portable enough to bring to the part, accurate enough for most quality checks, and much easier to maintain than a traditional gantry CMM.

I wish I had tracked how many times we avoided moving a part to the inspection room because someone just carried the arm over. Based on my rough logs, it's about 60-70 times a year. Each move saved 20 minutes of crane time and paperwork. That adds up.

Tip: When pricing a FARO CMM arm, ask about service packages. Our arm needed calibration after a drop—didn't think it would happen, but it did. The $2,500 repair would have hurt a lot more without the prepaid plan. Total cost of ownership includes those "what are the odds" moments.

Scenario C: Electrical Checks, Basic Sensors, and the "Cheap Stuff"

Now, not everything needs a six-figure metrology system. Sometimes you just need to check if a voltage is live or if an efector pressure sensor is reading correctly. That's where a Fluke multimeter comes in. And yes, I get the question "which Fluke multimeter do I need" a lot.

I don't have hard data on which model is best for every purpose, but my rule is: never go below the 17B+ if you're doing anything safety-critical. The cheaper 10 multimeter? It worked fine for a while, but when it gave a wrong reading on a 480V circuit, we almost had an accident. The $40 savings nearly cost us a lot more.

But here's the nuance: Don't let the brand allure fool you. If all you need is a go/no-go for a pressure switch, a basic efector sensor with a local indicator is often cheaper and more reliable than rigging up a full data acquisition system. The TCO of over-specifying measurement tools is real—you pay for complexity you don't use.

How to Decide Which Scenario You're In

In conversations with our operations manager, we use three quick questions:

1. What's the largest dimension you need to measure? More than 3 meters → laser tracker. 0.5 to 3 meters → CMM arm. Under 0.5 meters → maybe a handheld tool or gauge.
2. How often does the part move? If it's stationary and large, bring the tracker to it. If it's on a pallet, bring the arm. If you're chasing it down a line, you need a portable solution.
3. What's the risk of bad data? Safety-critical or high-value → invest in accuracy. Quick pass/fail with low consequence → a basic meter or sensor might suffice.

I should add that I once skipped the last question and ordered a cheap pressure sensor for a pneumatic safety circuit. It drifted after two weeks. The downtime from an unexpected shutdown cost us $3,200 in lost production. So now I always ask: what happens when the measurement is wrong?

Looking back, I should have built a simple TCO spreadsheet from day one. The FARO laser tracker, the CMM arm, even the basic Fluke multimeter—each has a place. The trick is matching the tool to the job, not the brand to the budget.