Questions to Ask When Buying a Used CMM

Buying a used Coordinate Measuring Machine (CMM) can feel like a smart move for manufacturers looking to save money. After all, a used system can cost up to 30% less than new equipment, making it look like a bargain. But without asking the right questions, that bargain can quickly turn into a money pit. To make the right decision, manufacturers need to treat CMMs not just as an expense, but as an investment in accuracy, productivity, and longevity. Here are the most important questions to ask when buying a used CMM and why they matter.

Buying a Used CMM

1. What’s the Long-Term Investment Value?

CMMs shouldn’t be seen as a short-term purchase. A properly maintained and recertified machine can last decades. The question isn’t just about upfront price, it’s about longevity, productivity, and the value of having a system that won’t fail when you need it most.

2. How Will This Win Over the C-Suite?

Often, it’s the quality engineer advocating for a better CMM, while the CFO or president focuses on the price tag. Quality leaders should prepare to answer the C-suite’s concerns by highlighting longevity, reduced downtime, and the measurable savings of buying right the first time.

3. How Do I Keep This CMM Running for Decades?

Ask about a post-sale checklist. Ideal lab conditions include:

  • Stable air pressure and clean air supply
  • Controlled humidity and temperature stability
  • Proper vibration isolation systems

These factors determine whether your CMM delivers decades of accurate measurements or breaks down frequently or even permanently.

4. What Services Come After the Sale?

A CMM purchase should include more than hardware. Does the provider offer:

  • Full service support including installation, setup, and calibration?
  • Training for your operators from software and proper CMM usage?
  • Parts replacement, upgrades, and calibration?

The right partner supports you through the entire lifecycle, not just at the point of sale.

5. What Size of CMM Fits My Needs?

Not all CMM purchases are equal:

  • Part Size: A great rule of thumb is to add, on average, 600 mm to the size of your largest part’s dimensions to get the ideal CMM size
  • Part Geometry Complexity: The more complex the part’s geometry, the larger the CMM’s measurement volume should be to allow the probe head to get access to all of the part’s features.
  • Inspection Volume: If you are measuring dozens to hundreds of parts a day, you might be able to utilize a multi-up fixture to reduce the time for part placement and fixturing.

6. How Accurate Does the CMM Need to Be?

Many buyers overspend on precision they don’t actually need. In metrology, accuracy is tied to uncertainty percentages. For example, aerospace and medical industries often require measurements at 10% uncertainty. That means if your tolerance is five ten-thousandths, your measurement device needs to measure at one-tenth that level.

7. What’s Involved in Relocating the CMM?

Moving a CMM isn’t as simple as loading it on a truck. Ask about:

  • Proper bracing and rigging
  • Transport conditions
  • Reinstallation, calibration, and recommissioning at your facility

Relocation can easily add $20,000 or more if not planned correctly.

8. What About Software and Hardware?

Some CMMs are sold without software, leaving buyers stuck with additional costs. Ask whether software, controllers, and probe heads are up to date. Old electronics often fail quickly, making the system unreliable.

9. Am I Buying a Money Pit?

The most important question: Is this machine truly an investment, or a liability waiting to happen? Without warranties, updated electronics, and service backing, a low-cost CMM can drain budgets through constant repairs.

Buying a Used CMM: The Bottom Line

There are many questions to ask when buying a used CMM and skipping them can cost your business thousands. By focusing on longevity, service, accuracy, and lifecycle support, you transform a risky purchase into a smart investment.

Don’t risk buying a money pit. Contact Made to Measure Metrology today to learn how our recertified CMMs can deliver decades of reliable performance backed by full service and training.

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