guide bar is graduated in degrees at one end and in
inches per foot of taper at the other end to provide for
rapid setting. Figure 6-78 is a view of the end that is
graduated in inches per foot of taper.
When you prepare to use the taper attachment, run
the carriage up to the approximate position of the
work to be turned. Set the tool on line with the center
of the lathe. Then, bolt or clamp the holding bracket
to the ways of the bed (the attachment itself is bolted
to the back of the carriage saddle) and tighten the
clamp (C, fig. 6-79). The taper guide bar now
controls the lateral movement of the cross slide. Set
the guide bar for the taper desired; the attachment is
ready for operation. To make the final adjustment of
the tool for size, use the compound rest feed screw,
since the cross-feed screw is inoperative.
There will be a certain amount of lost motion or
backlash when the tool first starts to feed along the
work. This is caused by looseness between the
Figure 6-78.--End view of taper guide bar.
Figure 6-79.--Turning a taper using taper attachment.
6-45