Powermatic 3520B - Manual (Page 25)

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Turn off the lathe and use a brush or paper
towel to apply the finish. Remove excess finish
before restarting lathe. Allow to dry and sand
again with 320 or 400 grit sandpaper. Apply
second coat of finish and buff.
Face Plate and Bowl Turning
Face plate turning is normally done on the
inboard side of the headstock over the bed.
Larger workpieces must be turned on the
outboard side (remove tailstock and tool support
base, and move headstock to opposite end of
bed - see Figure 9).
Mounting Stock
Use of a face plate is the most common method
for holding a block of wood for turning bowls and
plates:
1. Select stock at least 1/8" to 1/4" larger than
each dimension on the finished workpiece.
2. Always select the largest diameter face plate
that can be used for the workpiece to be
turned.
3. True one surface of the workpiece for
mounting against the face plate.
4. Using the face plate as a template, mark the
location of the mounting holes on the
workpiece, and drill pilot holes of the
appropriate size. Face plates are drilled for
No. 12 screws. (Phillips and square drive
screws will hold up better than slotted
screws. Sheel metal screws are case
hardened with deeper and sharper threads
than wood screws.)
If the mounting screws on the face plate
interfere with the workpiece, a glue or waste
block can be used:
5. Make a block the same diameter as the face
plate, Figure 37. Both waste block and
workpiece should have flat surfaces for
gluing.
6. Glue the block to the workpiece. Avoid using
brown paper or newspaper between the
waste block and workpiece. It may work fine
if you are using scrapers, but a slight catch
with a bowl gouge can separate the two.
NOTE: When using a waste block, be careful
with the adhesive you select. Dry workpieces
can be bonded with ordinary white or yellow glue
but must be clamped to ensure a good bond.
Green workpieces require cyanoacrylate type
glue.
Figure 37
Faceplate or Chuck?
While faceplates are the simplest, most reliable
method of holding a block of wood for turning,
chucks can also be used. As there are dozens
of chucks to choose from, the woodturner should
first consider all the different types of turning that
will be done, and read reports or discuss with
other turners who own chucks before making a
decision.
A chuck is not a requirement, but is handy when
working on more than one piece at a time.
Rather than removing screws, you simply open
the chuck and change workpieces.
The most popular ones are four jaw scroll
chucks with a variety of jaws to accommodate
different size tenons. Most also come with a
screw chuck as well.
Wood Selection
Firewood is the cheapest, most widely available
stock to use while learning to turn bowls. Simply
waste wood for a while practicing turning
techniques. Develop skill with each tool before
attempting to make a finished piece. It is best to
start with dry wood, without worrying about
drying or distortion. Once turning becomes
comfortable, try green wood which cuts very
easily. As the turner gains experience, he or she
will find extraordinary grain and figure in the
form of burls, crotches and bark inclusions.
Checks and Cracks
Green wood will check and crack. For best
results, leave logs in as long a length as you can
handle. As the material starts to dry, surface
cracks will develop on the ends of the log. Cut
off two to three inches and you should find good,
sound wood. Also cut the log in half along the
pith to avoid having it in the finished piece. Most
checks radiate from the pith.