Diagnose Center für Schleiftechnik von THELEICO

Diagnostics centre

Tips from our experts

Here you will find possible solutions to problems that can occur during grinding. In this respect, the symptoms observed on the machine, the possible causes and help or correction suggestions are listed. In some cases there are different causes and several solutions for one symptom.

If you have further questions, please consult our experienced application engineers:
Tel. +49 (0) 291 / 9901-0, Email This email address is being protected from spambots. You need JavaScript enabled to view it.

Select the relevant problem field for the diagnostics process:

Symptom Cause Solution
Chatter marks at regular
?Vibration in the machine Check machine bearings for wear
Chatter marks in checked pattern Disc not balanced or deformed Balance or redress disc
Irregular chatter marks Disc fastening unstable or workpiece loose Tighten disc fastening or fasten workpiece
Irregular surface scratches /Disc too soft Coolant dirty
Reduce workpiece speed
Use harder disc
Coolant dirty Replace coolant
Check filter
Spiral-shaped marks Dressing techniques not optimal Check diamond for sharpness and fixation
Check parallelity of dresser
Surface too rough (coarse) Disc too coarse Use fine, slow dresser
Use fine-grained disc
Disc too soft Use workpiece speed
Use harder disc
Metal deposits on the disc Dress more often
Use softer, more open disc

Symptom Cause Solution
Disc not dimensionally stable Disc too soft Increase work speed
Use harder disc
Disc too coarse Use finer-grained disc
Burn marks on diameter Disc too hard Reduce work speed
Use softer disc
Use easier cutting abrasive
Burn marks on flanges Rub disc edges on the shoulder Relief grind dressing disc edges
Coolant short Increase coolant flow to contact area
Workpiece not parallel Dirt in the centring holes Clean and lubricate holes
Workpiece incorrect Check alignment - align
Workpiece bends Use counterholder
Excessive wear on disc Reduce work speed
Dress slow and fine
Disc moved beyond the end of workpiece ? disc when grinding 1/2 to 1/3 of its width with the workpiece ?
Workpiece not round Disc too hard Reduce work speed
Dress coarser
Use softer disc
Workpiece incorrectly aligned check holes and chuck centring
Disc will not cut Disc is shiny Reduce work speed
Dress coarsely
Use softer grade disc

Symptom Cause Solution
Non-round workpiece Workpiece set too low Increase cutting height using holes
Disc too hard/fine Increase regulating wheel speed
Reduce operating power
Make disc grippier by dressing coarse and fast
Reduce cutting depth
Use softer/coarser disc
Uneven dimensions Varying cutting depth Set balancing feed
Ensure constant grinding allowance
Check taper and non-roundness
Workpiece not parallel Regulating wheel incorrectly dressed Check settings and redress regulating wheel
Cutting edge incorrectly set or workpiece cutting edge worn Check and adjust
Diamond worn Check and adjust/replace
Workpiece guides incorrectly aligned Check guides and adjust
Disc is acting soft Lower dressing speed
Use harder disc
Reduce cutting depth
Rods not straight - through grinding Rods are not straight before grinding Straighten rods
Workpiece guides / workpiece-
cutting edge incorrectly aligned
Check and adjust
Heat build-up Reduce cutting depth

Symptom Cause Solution
Abrasive detachment Disc too soft Use harder disc
Failure of the corners Disc too soft Use harder disc
Disc too coarse Use finer grain size and/or harder disc
Vibration Faulty dressing Dress more frequently
Disc too coarse for size of cast iron piece Use disc with feiner grain size
Disc too hard Use softer disc

Symptom Cause Solution
Non-round Workpiece distortion due to too high clamping pressure Reduce clamping pressure
Overheating of the workpiece leads to uneven workpiece Use softer, cutting disc
Increase expansion of coolant feed
Workpiece fastening not round Check and correct alignment
Widened hole on the ends bigger than in the middle Disc moves out too far at both ends of the hole Reduce stroke length so that only 1/3 of the disc length protrudes from the hole after the stroke
Holes not parallel Incorrect honing movement or length Check that it does not move out more than 25% of the honing length. Check that back edge of the honing tool passes midpoint of the hole length
Inadequate surface quality Bench speed too high Reduce bench speed

Symptom Cause Solution
Unevenness on workpiece Distorted workpiece due to magnet holder, springs back when removed from the bench Reduce clamping pressure
Low material removal, high segment wear and low power consumption Segment too soft Use harder segment
Segment too fine Use coarse-grained segment
Motor not working, low material removal and high power consumption Segment too hard Use softer segment
Reduce bench load
Cross-grinding angle too big
Incorrect ratio between rotating, forward and backward speeds Increase rotating speed and/or reduce forward and backward speed

Symptom Cause Solution
Burn marks, burnishing or cracking Insufficient coolant Check outlet tug and position of the lead
Cooling mixture does not match the specification Check thinning
Disc too hard Reduce planing speed of the disc
Coolant degeneration Replace coolant