Keep this card with the machine or in your CNC toolbox.
IF SOMETHING DOESN’T LOOK OR SOUND SAFE — STOP.
Don’t continue testing simply to finish the checklist.
1 — STOP & DOCUMENT
☐ Stop the machine.
☐ Don’t immediately restart the program.
☐ Look at the setup before moving anything.
☐ Take photos of the collision area and witness marks.
☐ Record any alarm or error message.
☐ Identify what was moving.
☐ Identify what made contact.
What Hit What?
☐ Cutter → Material
☐ Cutter → Clamp
☐ Cutter → Fixture
☐ Cutter → Spoilboard
☐ Holder / Collet Nut → Obstruction
☐ Dust Shoe → Obstruction
☐ Spindle → Obstruction
☐ ATC / Holder / Fork → Obstruction
☐ Rotary / Vertical Setup
☐ Other: ______________________________
Where the contact occurred helps determine what should be checked next.
2 — CHECK WHAT WAS EASIEST TO MOVE
Before assuming the machine moved, check:
☐ Cutter
☐ Tool holder
☐ Collet / collet nut
☐ Workpiece
☐ Clamps
☐ Fixture
☐ Dust shoe
☐ Spoilboard
☐ Tool number
☐ Tool length / offset
☐ Work offset
☐ Material thickness
☐ Program / setup information
Check everything that was easier to move than the machine before assuming the machine moved.
3 — INSPECT THE TOOLING CHAIN
Spindle → Holder → Collet → Cutter → Cutting Edge
☐ Inspect the cutter for damage.
☐ Check whether the cutter slipped in the collet.
☐ Inspect and clean the collet.
☐ Inspect the collet nut.
☐ Inspect the holder taper.
☐ Inspect the spindle taper.
☐ Quarantine questionable tooling.
Label questionable holders:
BUMP — CHECK BEFORE USE
☐ Install known-good tooling for diagnostic testing.
Every precision part between the spindle bearings and the cutting edge affects the quality of every part you produce.
4 — CLEAN BEFORE YOU MEASURE
☐ Clean spindle taper with the proper non-abrasive tool.
☐ Clean holder taper.
☐ Clean collet.
☐ Clean cutter shank.
☐ Remove debris from ATC rack / forks where applicable.
☐ Clean measuring surfaces and reference tools.
KEEP PRECISION MATING SURFACES CLEAN AND DRY
Unless the manufacturer specifies otherwise, don’t apply oil, grease, wax, or rust inhibitor to spindle tapers, holder tapers, collet gripping surfaces, or cutter shanks.
Never diagnose a precision problem through a layer of dust.
5 — HOME & MOVE
Clear the machine before moving it.
☐ Machine area clear.
☐ Clamps and fixtures clear.
☐ Dust shoe clear.
☐ Cables and hoses clear.
☐ Home the machine normally.
Does it home normally?
☐ YES
☐ NO — STOP
Jog one axis at a time.
☐ X moves normally.
☐ Y moves normally.
☐ Z moves normally.
☐ Rotary / Vertical system normal where applicable.
STOP IF YOU FIND:
☐ Binding
☐ Grinding / scraping
☐ Jerking
☐ Severe or unusual vibration
☐ Unpredictable movement
☐ Homing / sensor problem
Normal movement comes before cutting accuracy.
6 — CHECK THE SPINDLE
☐ Install appropriate known-good tooling.
Never run an ATC spindle empty.
☐ Perform normal spindle warm-up.
☐ Listen through normal operating speeds.
☐ Sound normal.
☐ Vibration normal.
☐ Acceleration / deceleration normal.
☐ Temperature behavior normal.
STOP FOR:
☐ Grinding / scraping
☐ Severe or increasing vibration
☐ Rapid or unusual heating
☐ Smoke / burning odor
☐ Improper holder seating
☐ Spindle alarm
☐ Other abnormal behavior
7 — CHECK THE ATC
If equipped:
☐ Inspect rack and forks.
☐ Inspect holders.
☐ Check air pressure / air system.
☐ Verify spindle-cone cleaning air blast.
☐ Clear the complete tool-change area.
FIRST TOOL CHANGE — SLOW & VISUAL
Watch:
☐ Approach
☐ Holder return
☐ Release
☐ Pickup
☐ Seating
☐ Clamp
☐ Departure
☐ Correct tool identification
THEN CHECK EVERY POSITION
☐ All 7 / 10 / 12 positions verified as applicable.
STOP FOR:
☐ Strike or drag
☐ Holder seating problem
☐ Release / clamp problem
☐ Damaged fork
☐ Tool identification mismatch
☐ Tool-drop risk
☐ Abnormal repeated sound or movement
Never interrupt a tool change unless safety requires it.
If interrupted, verify that the physical tool positions and the control agree before continuing.
8 — MAKE THE MACHINE PROVE IT
Use the protected Diagnostic Program Library.
Start with familiar tests.
☐ Script Test
☐ Square
☐ Circle
☐ Triangle / Diamond
☐ Pocket & Plug
☐ Repeated Feature
☐ Hole Pattern
☐ Return to Origin
☐ Small Surfacing / Tram Test
Compare with the Healthy Machine Baseline.
Ask:
Does today’s result look, measure, sound, and fit like the healthy machine?
☐ YES
☐ NO / NOT SURE
9 — MEASURE ONLY WHEN THE EVIDENCE GIVES YOU A REASON
If a diagnostic test shows meaningful change:
☐ Runout
☐ Return-to-position
☐ Repeatability
☐ Squareness
☐ Circle geometry
☐ Tram
☐ Fit
☐ Other: ______________________________
Before measuring, ask:
What question am I trying to answer?
☐ Clean the measuring setup.
☐ Use known-good tooling.
☐ Repeat the measurement.
☐ Record the results.
☐ Compare with the Healthy Machine Baseline.
One reading is an observation; a repeatable reading is evidence.
Don’t adjust the machine while you’re still trying to understand the problem.
Measure first. Understand second. Adjust only when the evidence identifies what needs adjustment.
10 — MAKE THE DECISION
GREEN — RETURN TO WORK
☐ Machine agrees with Healthy Baseline.
☐ No meaningful or repeatable change identified.
ACTION
Record the event.
Return to production deliberately.
Watch the first production run.
Get back to woodworking.
YELLOW — INVESTIGATE
☐ Something changed or remains unexplained.
ACTION
Repeat the relevant test.
Verify the setup.
Eliminate tooling and other easy variables.
Change one variable at a time.
Compare again with the Healthy Baseline.
DON’T GUESS. INVESTIGATE.
RED — STOP
☐ Unsafe condition
☐ Abnormal movement
☐ Severe vibration
☐ Spindle / holder concern
☐ ATC strike or tool-retention concern
☐ Significant repeatable change
☐ Continuing could cause additional damage
ACTION
STOP TESTING.
Preserve the evidence.
Complete the Machine Event Snapshot.
Contact technical support or qualified service personnel.
Red describes the next decision—not necessarily the size of the repair.
MACHINE EVENT SNAPSHOT — QUICK NOTES
Date: ______________________________
Operator: __________________________
Machine: ___________________________
Program: ___________________________
What happened?
What made contact?
Tool Number: _______________________
Cutter: ____________________________
Holder / ATC Position: _____________
Alarm / Error:
What Passed?
☐ Visual Inspection
☐ Homing
☐ X Motion
☐ Y Motion
☐ Z Motion
☐ Spindle
☐ ATC
☐ Script
☐ Square
☐ Circle
☐ Fit
☐ Other: ______________________________
What Failed or Changed?
Measurement / Baseline Difference:
Photos / Video Taken?
☐ YES
☐ NO
FINAL STATUS
☐ GREEN — RETURN TO WORK
☐ YELLOW — INVESTIGATE
☐ RED — STOP / CONTACT SUPPORT
BEFORE YOU CLOSE THE EVENT
Once the machine is healthy and back in service, ask:
What simple change could prevent this event from happening again?
☐ Lower / safer workholding
☐ New no-go zone
☐ Revised toolpath
☐ Safe-Z change
☐ Tool-table correction
☐ Work-offset verification
☐ Startup / Cycle Start checklist
☐ First-run procedure
☐ Machine-handoff rule
☐ ATC procedure
☐ Fixture change
☐ Other: ______________________________
Prevention Action
THE AFTER THE BUMP RULE
Don’t adjust first.
Don’t measure first.
Don’t cut first.
STOP → DOCUMENT → INSPECT → CLEAN → TEST → COMPARE → DECIDE
If the machine passes, get back to work.
If it doesn’t, give technical support the information needed to help you get up and running as quickly as possible.
Then use what you learned to make the next bump less likely.