Reamers Guide
Information on Reaming

REAMING RECOMMENDATIONS by The Tap & Die Co, London

 Choice of Reamer:
 Straight Flute reamers may have advantage in blind holes, since lefthand spiral flutes tend to push swarf forward. Generally speaking the standard range of reamers will suffice for reaming most ferrous and non-ferrous metals.

 Reaming Speeds:
 Should be approximately 50% of the speed used for drilling the same material. Faster speeds are generally not an advantage , but may be possible in exceptionally rigid and efficient designs. Chatter degrades the surface finish and must be strictly avoided.
 Refer our ‘Drills Guide’ and ‘Drill Speeds’ in our 'Technical Data'

 Reaming Feeds:
 Should be approximately 100% greater than the feed used for drilling the same material. Insufficient feed may degrade the finish and roundness of the hole and increase tool wear.

 Coolants:
 Should be as that recommended for drilling. Adequate coolant supply ensures a good surface finish

 

 Reamers Guide for Predrilling Diameters for Reaming (Recommended):
 DIAMETER OF REAMER

   PREDRILLING DIAMETER

  Two-flute drill   Core Drill
   mm    inch  mm  inch  mm  inch
   2 - 6   1/16 - 15/64  -0.2  -.008  -0.2  -.008
   6 - 10   15/64 - 25/64  -0.3  -.012  -0.25  -.010
  10 - 14   25/64 - 9/16  -0.4  -.016  -0.25  -.010
  14 - 18   9/16 - 23/32  -0.5  -.020  -0.3  -.012
  18 - 30   25/64 - 9/16  -0.6  -.024  -0.4  -.016
  30 - 50   1.3/16 - 2  -1.0  -.040  -0.5  -.020

 Notes: For hand reaming rather less stock may be left in order to reduce the effort required. We suggest the nearest standard drill diameter to the calculated diameter from the above table will be acceptable. Special drill diameters should not be required for predrilling

The Tap and Die Company website has a lot of other very useful 'Technical’ Data & Information for you to view