58 Troubleshooting Guide Check the obvious first . Before changing the grinding wheel specification, investigate the following most common causes for most grinding problems: 1 . Diamond dressing tool condition (check if worn or dull, rotate tool or replace if necessary) 2 . Coolant direction, volume & filtration 3 . Wheel dressing procedures (dress more open to free up cut rate, dress more closed to improve finish) Problem Possible Cause Correction Burn Poor coolant direction Redirect coolant into grinding zone   Restricted or low coolant volume Increase coolant volume Wheel too hard Use one grade softer wheel Wheel structure too closed Use porous bond wheel Wheel dressed too fine Dress wheel coarser, more “open” Worn dressing tool Inspect, rotate or replace dressing tool Work speed too slow Increase work speed Infeed too fast Reduce stock removed per pass or upgrade to 5SG Loading and Glazing Wheel too fine Use coarser grit or softer grade wheel Wheel too hard Use one grade softer wheel Too durable abrasive Use a sharper more friable abrasive Poor coolant quality Change coolant or use high detergent type Wheel structure too closed Use a porous bond wheel Wheel too finely dressed Dress wheel very open Diamond dressing tool worn Replace diamond and dress coarse (open) Depth of cut too small Increase feed and traverse speed Chatter Unsupported work Increase work support Machine vibration Check for worn bearings Too heavy cut rate Reduce cut rate Wheel too hard Use one grade softer wheel Wheel structure too closed Use a porous bond wheel Wheel out of balance Check wheel balance or try new wheel Chatter marks on workpiece Worn spindle bearings Check and correct for truth and end play Wheel out of truth Redress wheel and check mounting Poorly clamped wheel Check tightness of mounting nuts Glazed face of wheel Redress wheel with sharp dressing tool Poor surface finish Incorrect wheel dress Dress wheel finer (slow down dressing tool traverse) Worn dressing tool Inspect, rotate, or replace dressing tool Too coarse grit size Use a finer grit size Wheel too hard Use softer grade Not holding form Wheel too soft Use one grade harder wheel Wheel structure too open Use a more closed wheel structure Not holding corner Incorrect wheel dress Dress wheel finer .   Face and side true wheel Too large grit size Use smaller grit size (maximum grit diameter less than 1 . 5 times corner radius) Wheel too soft Use harder grade wheel Wheel structure too open Use more closed structure wheel