The signs of dulling
Dulling is gradual rather than sudden, so operators adapt to it and may not notice. The measurable signs are:
- Burn marks or fuzzing on the cut surface
- The machine labouring; a change in noise and vibration
- Needing to reduce the feed rate
- Dimensional drift and the cut face losing squareness
What deferring maintenance really costs
Working with a dull tool does more than lower surface quality. A labouring machine draws more energy, bearings and spindles wear faster, and the waste rate climbs.
Each of these looks small on its own, so the total usually goes unnoticed — while the cost of regular sharpening stays small beside it.
How to set the interval
Giving a fixed number of days is not right; the interval depends on the material, the section and the daily running time. Resinous material and thick sections tire a tool faster.
The practical method is to record, over the first few cycles, the point where cut quality starts to fall off, and to fix the maintenance interval just before it.
Repair under the same roof
Besides sharpening, repair is available for damaged tools. Asking whether a tool can be repaired before replacing it is usually the more economical route.