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I
will describe the method used to construct the Capstans for my HMS
Warrior of 1781 and my Oliver Cromwell. No dimensions will be given
since actual dimension will depend on your scale.
Tools
used were the usual files and xacto knives, and drills. I also used
a Sherline Lathe, and a Sherline Mill with the Indexing attachment
P/N 3200.
In
making the barrel for the Capstan a dowel of the correct diameter
is needed. I wanted to use boxwood. Boxwood dowels are not available
so I chucked a square piece of box in the four-jaw chuck and turned
it to the diameter needed. I always make one or two spares when
making any repetitive parts like this. The set up is what takes
the time. Far better to make extras while the set up is ready than
to try to set up again and find minute dimensional differences.
Make
each dowel about 1 ½ or so inches longer than needed. This
will give you the necessary length to hold in the chuck while working
on the open end. I also turned a small diameter on the end that
will become the base. This part will be inserted into the partner
to mount the capstan.
With
suitable diameter dowel prepared, set up the Indexing Attachment
(IA) on the Mill. Attach your three-jaw chuck to the IA and chuck
up a piece of dowel. Make sure you have enough length of dowel exposed
to match the needed height of your capstan plus about a ½
to ¾ ". The extra is to allow clearance for the head
of the mill when you cut your slot. Make sure everything is tight
and set the index to O. Select an appropriate mill. Use metal cutting
mills. An exact size mill is great but if you do not have the exact
size you need then use one slightly smaller.

Do not try to make the depth of the cut in one pass. Make several
shallow cuts to keep form splintering out the wood. Making too deep
a cut may also cause the dowel to deflect and even break it out
of the chuck. Cut a slot to the calculated depth. If you need a
wider slot than your mill, move the table in or out half the extra
width needed and cut, then move it in the other direction half the
required extra distance. Always keep track of where your zero position
on the table is and return to that before beginning the next cut.
Always allow for backlash. Now rotate the IA 60 degrees and repeat.
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