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Chuck jams on lathe
spindle
This is a common problem with fixtures on a lathe. To
help prevent it try a plastic or fiber washer between
insert/chuck and spigot shoulder of spindle. Greasing of
insert face and spindle can also help.
Note
Use of plastic spindle washers could affect accuracy.
Safe Lock Woodworm
screw creeps forward or
is not seated properly in
chuck
Ensure the Safe Lock Woodworm screw is placed
correctly between jaw slides and behind the jaws
Wooden tenon shifts
during turning
Check that the tenon area is made correctly for jaws to
grip. Check that the tenon is not oversized or
undersized.
See tenon operation instructions.
Use careful chisel techniques that do not exert
excessive pressure. Irregular rough wood blanks need
to be checked to see if there is enough jaw surface
contact.
Wood blank does not seat
properly in internal
mortise mounting
Check the angle of the dovetail made in the mortise is
the same angle as the jaws. Make sure the bottom of
the recess is flat and square to face.
Check that the bowl is not incorrectly riding on the flat
shoulder of at the base of the jaws.
Chuck runout inspection procedure
The runout tolerance is specified at the chuck body and not on the workpiece.
Generally, wood is a flexible material which makes it an insufficient medium to
measure accuracy. Radial runout values on a workpiece is amplified as the length of
the workpiece increases therefore the measurements must be taken at the chuck
body to standardize the procedure.
Equipment Required
A Dial Test Indicator (DTI) is required to inspect and quantify the level runout on the
chuck.
