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•
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 46
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 47
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 _/8"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 48 - 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 7M' 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.
•
Then, remove the stock. Place your jig over the turned
end, with turned portion through the smaller jig hole, and
recenter the stock on the lathe.
•
Hold the jig firmly and start the lathe.
•
Push the jig slowly right to left along the stock until the
whole dowel is completed.
Figure 49
MISCELLANEOUS
OPERATIONS
GUIDE BLOCKS FOR SCRAPING OPERATIONS
A guide block can be clamped to a chisel to limit the depth of
cut and aid in the production of perfect cylinders, tapers and
facings on faceplate turnings. Scraping methods must be
used when the guide block is employed.
Figure 50
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