Somta - page 53

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(b) Possible Cause
Speed too high or feed too low.
Solution
Use the recommended speed/feed -see page 40/41.
(c) Possible Cause
The workpiece material is too hard.
Solution
Use a HSS-Co reamer.
Tapered or Bell-Mouthed holes
(a) Possible Cause
Mis-alignment of the reamer and the hole.
Solution
Align the reamer and the hole.
(b) Possible Cause
The machine spindle and/or bearings are worn.
Solution
Only use equipment which is in good condition.
Reamer rubbing and not cutting
(a) Possible Cause
Too little reaming allowance in the hole.
Solution
See table of stock removal on page 38.
(b) Possible Cause
Reamer re-sharpened with too little or no relief on the bevel
lead.
Solution
Re-grind the bevel lead to a 6°- 8° relief.
Oversized holes
(a) Possible Cause
Excessive run-out on the machine spindle or holding device
eg. taper sleeve, collet or chuck.
Solution
Only use equipment which is in good conditon.