23
Parting Tool - 1/8", used for scrap ing, making a
cut-off, or to s et diameters for s izing.
Figure 35
Basic Tu rning Tools
For safety and best perfo rm anc e, keep tools sharp.
If a tool stops cutting or requires excessive
pressure to make a cut, it needs to be sharpened.
A number of brand name sharpeni ng jigs and
fixtures are available; however, a woodturner
should lear n to sharp en tools f reehand.
For best results, use a slow speed grinder (1800
rpm) fitted with a 60-grit aluminum oxide wheel (for
shaping) and a 100-grit alum. oxide wheel (for final
sharpening and touchup). The grinder should be
located ne ar your lathe and at a c omfortable
height. A diamond dre sser will keep the wheels
true and eli minate gl azing.
Never allow the tool to rest in one place on the
wheel, keep it m oving and use a light touch.
Carbon steel tools can overheat easily and should
be cooled frequently. If the edge turns blue, it has
lost its temper and should be ground past the blue
area. High-speed steel tools are not as likely to
overheat, but can be damaged if allowed to get red
hot. High-speed steel tools should not be
quenched for cooling. Honing with a diamond lap
or slipstone will save trips to the g rind er and keep
the edge fresh.
11.3 Spindle Turning Spindle turning takes place between the centers of
the lathe. It requires a spur or drive center in the
headstock and a live or dead center in the tailstock.
A cup center rathe r than a cone ce nter in the
tailstock will ofte n reduce the ris k of splitting the
stock.
Figure 36 shows the basic profile shapes in spindle
turning.
Figure 36
11.4 Stock Selection Stock for spindles should be straight grained and
free of checks, cracks, knots and other defects. It
should be cut 1/8" to 1/4" larger than the finished
diameter and may require additional length so the
ends can be removed later. Larger stock should
have the corners removed to produce an octagon
making the piece easier to rough down to a
cylinder.
1. With a comb ination squa re, or plas tic center
finder f or ro und sto ck, loc ate and m ark c e nter
on each end of the workpiece. Accuracy is not
critical on full rounds but extremely important
on stock where square sections are to remain.
Put a dimple in the stock with an awl or nail, or
use a spring-loaded automat ic center punch.
2. Extremely hard woods may require kerfs cut
into the ends of the stock (Figure 37) using a
band saw, so the wood will accep t the spur
center and t he live ce nter.
Figure 37