Some sparks can be normal when grinding steel. Heavy sparks, strong heat, discoloration, or a “burned” finish usually mean you’re using too much pressure, too much speed, or you’re overheating the blade.
Do this immediately:
- Stop and let everything cool:
Heat buildup is one of the main reasons for poor results and faster wear. Let the blade and grinding head cool down completely.
If you see blue/purple discoloration on the blade edge, that’s a sign of overheating
- Reduce pressure and speed:
Use light pressure only. Start at the lowest drill speed and increase only if necessary. Stay under 2500 RPM.
- Avoid long contact in one spot:
Keep the blade moving slowly and evenly. Staying in one spot creates excess local heat and poor finish.
- Sharpen fewer blades per minute:
Sharpen a maximum of 1 blade per minute to avoid overheating.
- Check blade material:
If you’re attempting carbide: stop. Carbide is not suitable and can cause rapid head wear and poor results.