Introduction
When purchasing used SMT pick and place machines, cost-effectiveness is only part of the equation. Ensuring performance and reliability is equally critical. Second-hand equipment can come with hidden problems that lead to component misplacement, production delays, or even line downtime. This article explores the 10 most common issues found in used SMT machines—and provides actionable solutions you can use to maintain efficiency and avoid costly repairs.
1. Feeder Not Feeding Tape Properly
Symptoms: Component tape doesn’t advance or gets stuck mid-process.
Causes:
- Worn or slipping one-way bearing on the tape reel roller
- Damaged gear or missing return spring
- Improper tension in tape mechanism
Fix:
- Replace worn-out bearings
- Clean feeder slot and recheck tension spring
- Use only compatible feeder types per brand
🔗 See our SMT Feeder Listings for tested replacements.
2. Feeder Floating or Misaligned

Symptoms: The feeder sits too high on the mounting base, causing nozzle collisions or mispicks.
Causes:
- Dirt buildup under feeder platform
- Improper seating or locking of feeder bracket
Fix:
- Clean feeder base regularly
- Inspect feeder mount for wear or damage
🛠 BUYSMT provides pre-cleaned feeders with mounting alignment checks.
3. Component Pickup Fails
Symptoms: Components are not picked up or are dropped during travel.
Causes:
- Clogged or damaged nozzle
- Weak vacuum pump
- Worn feeder push pin
Fix:
- Replace or clean nozzle
- Test vacuum pump performance
- Adjust or replace feeder pin
🔗 Check our full range of SMT Nozzles.
4. Vision System Failure
Symptoms: The machine fails to recognize fiducials or component orientation.
Causes:
- Camera calibration lost
- Lens dust or CCD aging
- Lighting system failure
Fix:
- Recalibrate camera
- Clean lenses with IPA
- Replace faulty vision modules
💡 BUYSMT offers tested machine vision kits with 24h performance burn-in.
5. XY-Axis Drift or Skew
Symptoms: Misalignment of component placement over time.
Causes:
- Stepper motor wear
- Dirty guide rails
- Encoder calibration drift
Fix:
- Re-lubricate axis rails
- Re-align encoder
- Replace faulty motors if needed
6. PCB Clamping Issues
Symptoms: The PCB is loose or warps during placement.
Causes:
- Worn clamping system
- Incorrect board thickness setting
Fix:
- Replace rubber clamp pads
- Reset board clamping gap parameters
7. Inconsistent Placement Accuracy

Symptoms: Components are slightly off-pad.
Causes:
- Vibration due to floor leveling issues
- Aging ball screw mechanism
- Poor machine leveling
Fix:
- Use vibration dampers
- Level the machine base
- Service ball screw regularly
8. Software Compatibility or Crashes
Symptoms: Old software not running or unable to read new CAD files.
Causes:
- Unsupported Windows versions
- Licensing issues
- Missing drivers for feeders or nozzles
Fix:
- Install updated offline programming software
- Use emulators if needed for old OS
- Choose machine models with active support
9. Air Pressure Problems
Symptoms: Low pickup rate or random nozzle drop errors.
Causes:
- Low air pressure or moisture in lines
- Air valve leaking
Fix:
- Maintain >0.6 MPa clean air supply
- Replace leaking air valves
10. Aging Electrical Systems
Symptoms: Sudden stops, error beeps, or intermittent power loss.
Causes:
- Faulty power supplies
- Relay contact aging
- Main board capacitor failure
Fix:
- Replace power modules
- Clean and inspect relays annually
- Use surge protection
Conclusion: Prevent Problems Before They Happen
Buying used SMT pick and place machines doesn’t mean accepting poor performance. With proper inspection, maintenance, and reliable parts sourcing, your production line can stay as efficient as a brand-new setup.
At BUYSMT, every machine undergoes:
- Full system test before shipping
- Feeder and nozzle compatibility check
- Free troubleshooting consultation
📞 Need help with troubleshooting your SMT machine?
Contact us today: www.buysmt.com/contact
Or explore our tested used SMT equipment catalog