| Category | Problem | Cause | Remedy |
|---|---|---|---|
| Threading with Dies | Poor finish (5/5) | Bar end not chamfered | Ensure bar end is chamfered |
| Reaming | Rapid Tool Wear | Insufficient stock to remove | Increase the amount of stock to be removed |
| Threading with Dies | Rapid wear (1/2) | Incorrect/lack of lubricant | Adjust conditions |
| Threading with taps | Rapid wear (1/3) | Wrong type of tap for application | Use tap with lower rake angle and/or higher relief and/or longer chamfer. Use coated tool. |
| Threading with Dies | Rapid wear (2/2) | Speed too high | Adjust conditions |
| Threading with taps | Rapid wear (2/3) | Lack of lubricant | Use good lubrication in order to prevent built up edge and thermal stress on cutting edge. |
| Threading with taps | Rapid wear (3/3) | Tap speed too high | Reduce cutting speed. |
| Counterboring and Countersinking | Rough Finish (1/2) | Dull cutting edge | Resharpen to original tool geometry |
| Counterboring and Countersinking | Rough Finish (2/2) | Wrong feeds & speeds | Increase speed - also try reducing feed |
| Milling | Short Tool Life (1/3) | Tough work material | Select the suitable tool |
| Thread milling | Short tool life (1/3) | Wrong cutting data | Reduce speed/feed |
| Counterboring and Countersinking | Short Tool Life (1/5) | Excessive cratering | Increase speed or decrease feed |
| Milling | Short Tool Life (2/3) | Improper cutting angle and primary relief | Change to correct cutting angle |
| Thread milling | Short tool life (2/3) | Instability | Check tool holder |
| Counterboring and Countersinking | Short Tool Life (2/5) | Abrasive material | Decrease speed and increase feed Increase coolant flow |
| Milling | Short Tool Life (3/3) | Cutter/workpiece friction | Use coated tool |
| Thread milling | Short tool life (3/3) | Rapid wear | Reduce speed |
| Counterboring and Countersinking | Short Tool Life (3/5) | Hard materials | Reduce speed - rigidity very important |
| Counterboring and Countersinking | Short Tool Life (4/5) | Insuffi cient chip room | Use larger diameter tool |
| Counterboring and Countersinking | Short Tool Life (5/5) | Delayed resharpening | Prompt resharpening to original geometry will increase tool life |
| Drilling | Spiral finish in hole (1/2) | Insufficient feed | Increase feed |
| Drilling | Spiral finish in hole (2/2) | Bad positional accuracy | Use a spot drill before drilling |
| Drilling | Splitting of the web (1/4) | Feed too high | Reduce feed to optimum rate |
| Drilling | Splitting of the web (2/4) | Insufficient initial clearance | Regrind to correct specification |
| Drilling | Splitting of the web (3/4) | Excessive web thinning | Regrind to correct specification |
| Drilling | Splitting of the web (4/4) | Heavy impact at point of drill | Avoid impact at the point of drill. Take care with taper shank drills when inserting / ejecting them from a spindle |
| Reaming | The tool clamps and breaks (1/6) | Worn out tool | Regrind to correct specification |
| Reaming | The tool clamps and breaks (2/6) | Back taper of the tool is too small | Check and replace / modify the tool |
| Reaming | The tool clamps and breaks (3/6) | The width of the land is too wide | Check and replace / modify the tool |
| Reaming | The tool clamps and breaks (4/6) | Workpiece material tend to squeeze | Use an adjustable reamer to compensate for the displacement |
| Reaming | The tool clamps and breaks (5/6) | Pre-drilled hole is too small | Decrease the amount of stock to be removed |
| Reaming | The tool clamps and breaks (6/6) | Heterogeneous material with hard inclusions | Use solid carbide reamer |
| Threading with taps | Undersize (1/5) | Wrong type of tap for application | Use spiral point for through hole or spiral flute for blind hole. Use coated tool to prevent built up edge. Use tap with higher rake angle |
| Threading with taps | Undersize (2/5) | Incorrect tolerance | Choose a tap with higher tolerance, especially on material with low oversize tendency, such as cast iron, stainless steel |
| Threading with taps | Undersize (3/5) | Incorrect or lack of lubricant | Use good lubrication in order ot prevent chip blockage inside the hole. |
| Threading with taps | Undersize (4/5) | Tap drill hole too small | Increase drill diameter to the maximum value. |
| Threading with taps | Undersize (5/5) | Material closing in after tapping | Adjust conditions |
| Reaming | Undersize hole (1/5) | Insufficient stock to remove | Increase the amount of stock to be removed |
| Reaming | Undersize hole (2/5) | Too much heat generated while reaming. The hole widens and shrinks. | Increase coolant flow |
| Reaming | Undersize hole (3/5) | The tool diameter is worn and is undersize | Regrind to correct specification |
| Reaming | Undersize hole (4/5) | Too low feed or cutting speed | Adjust cutting conditions |
| Reaming | Undersize hole (5/5) | Pre-drilled hole is too small | Decrease the amount of stock to be removed |
| Milling | Wear (1/5) | Workpiece material too hard | Choose correct tool with higher grade material and/or proper coating |
| Milling | Wear (2/5) | Improper feed and speed | Adjust cutting conditions |
| Milling | Wear (3/5) | Poor chip evacuation | Reposition coolant lines |
| Milling | Wear (4/5) | Conventional milling | Climb milling |
| Milling | Wear (5/5) | Improper cutter helix | Select the suitable tool |
| Milling | Workpiece inaccuracy (1/5) | Tool deflection | Choose a shorter tool and/or place shank further up holder |
| Milling | Workpiece inaccuracy (2/5) | Insufficient number of flutes | Use a tool with more flutes |
| Milling | Workpiece inaccuracy (3/5) | Loose/worn tool holder | Repair or replace it |