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RECOMMENDED SPEED
Always follow recommended speed to do spindle turning
depending upon the size and length of workpiece.
ROUGH FINISH
SQUARE LENGTH RPM RPM
to 2" 1 to 12" 1300 2000
to 2" to 24" 1100 2000
to 2" to 38" 1000 2000
2 to 4" 1 to 12" 1000 1800
2 to 4" to 24" 900 1600
2 to 4" to 38" 700 1400
4" Plus 1 to 12" 800 1400
4" Plus to 24" 600 1100
4" Plus to 38" 400 800
DUPLICATE TURNINGS
Identical turnings require great accuracy when plotting the
work and performing the various cuts. Many methods have
been devised to aid in perfecting the work.
Use of Patterns
Professional workers generally use a pattern or layout board. This
is a thin piece of wood or cardboard upon which is drawn a full-
size half section of the turning. The contour of the finished surface
is drawn first. Then, the diameters at various critical points are
drawn to scale as vertical lines intersecting the contour line.
By placing the pattern against the roughed-out cylinder, you
can quickly mark the various points of the critical diameters.
• To make each sizing cut, use outside calipers and set
these by actually measuring the length of the vertical lines
on the pattern which represent the diameters desired.
Make the sizing cut down to the proper diameter by using
the calipers to determine when the cut is finished.
• After making the sizing cuts, hang the pattern behind the
lathe where it will serve as a guide for completion of the
workpiece.
Figure 50
Using a Template and a Diameter Board
When many identical turnings are to be produced, it is conve-
nient to have a prepared template. This can be made of thin
wood or cardboard, it is cut on a band saw or scroll saw to
have the exact contour or the finished turning. The number
one finished turning can also be used as a template. Attach
the template to a board and then mount the board behind the
lathe, on hinges, so that the template can be moved down to
touch the workpiece and allow you to closely observe
progress of your work.
If a great many turnings are being produced, a diameter board
will save the time used for resetting calipers. This is simply a thin
board along the edge of which a number of semicircular cuts
have been prepared to represent all the various caliper settings
required for measuring the sizing cuts. Each semi-circular cut is
held against the workpiece instead of using the calipers.
Figure 51
Using a Template
Using a Diameter Board
LONG SPINDLES
A long turning can be worked in short sections, with joints
arranged to be at shoulders where they will not be noticed.
• Long thin work that is likely to whip while turning should be
supported at one or two places by a backstick. This is easy
to make. A simple backstick consists of a short length of
wood mounted vertically in an extra tool rest and notched
so that it can be used to support the spindle from behind.
An improved type, which uses 2 roller skate wheels to form
the notch, also is shown.
• Position the backstick against a pre-tumed portion near the
center of the spindle, this portion being at least YJ' over finish
size to allow for later removal of any marks made upon it.
• Operate lathe at a slower speed than normal. Lubricate the
workpiece at point of contact with the backstick. Use
beeswax (preferred), lard or grease.
• After completing the turning, remove the backstick and fin-
ish off the original point of contact. Sand off any slight
burns remaining on workpiece.
Figure 52 - Use of Backsticks
CUTTING DOWELS
Dowels of any size can be turned quickly with the simple jig
shown. If the stock is prepared as a split or quartered turning,
half round and quarter rounds will be produced.
The jig uses a _/2"gouge as the cutting tool and will produce
dowels up to 7/_6"diameter. Make the jig from suitable hard-
wood stock as shown.
• The hole through the jig must be large enough at the side
to the left of the gouge to allow passage of the square
stock. At the right of the gouge, this hole must be just the
diameter of the finished dowel. Make the jig so that you
can hold and guide it by hand.
• To start, center the stock like a spindle turning and turn
down about 2" at the right end to desired size.
Figure 53
15
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