Turning Between Centers

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Turning Between Centers (TBC) is a technique for eliminating the pen turning mandrel and it's problems with flex, out of round, and other alignment issues.   One barrel at a time is installed and turned.  The bushings used in this technique are specific to TBC, and cannot be used with a mandrel.  It may be possible to convert a standard bushing to use as TBC.

To use this technique, you will need

  • A 60 degree dead center installed in your lathe head stock.  It must match the MT taper of your lathe head stock.
  • TBC bushings for your pen.  These can be purchased from several individuals here on IAP and are much higher quality that the bushings normally supplied for mandrel turning.
  • A 60 degree live center for your lathe tail stock.

The bushings for this are usually specifically made for TBC.  Instead of a hole for a mandrel, there is a tapered recess that exactly matches the 60 degree live center or dead center.

A dead center is used in the head stock to drive the barrel, and a live center is used in the tail stock.  A dead center is commonly used in metalworking lathes and can be purchased from suppliers of such equipment.  Several individuals on IAP also sell these at reasonable prices.   

The bushings are inserted into one blank and the blank is put between the centers.  The dead center makes the blank spin, and the live center allows it to spin.

Now you just need to turn the blank as you would normally.  A minor advantage to this technique is the dead center will spin if you "catch" the blank.