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Tip
#56
Lathe Turning
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Faceplate
Turning
Faceplate
turning is similar to spindle turning in some respects, but
very different in others. We'll point out those differences
as we go through this basic procedure. As with spindle turning,
faceplate turning also involves six basic steps: Mounting,
rounding, sizing, shaping, sanding and parting.
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Figure
12-38.
Prepare stock for faceplate mounting by scribing the
outside diameter of your project and a circle slightly
larger than the faceplate on the surface.
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Mounting
To mount stock on a faceplate, first find the center of the
stock by drawing diagonal lines from corner to corner. Then
scribe the outside diameter of your project (the diameter
desired after rounding) on the stock. Also, scribe a circle
slightly larger than the diameter of the faceplate in the
center of the circle you've already marked (Figure
12-38). Then cut the stock round using a bandsaw or scroll
saw (Figure
12-39). This removes excess stock which makes turning
safer and easier.
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Figure
12-39.
Cut the workpiece into a circle to make turning it safer
and easier.
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Figure
12-40.
Glue a scrap block and your turning stock together,
center-to-center. Put a piece of paper (brown craft
paper or grocery sack) between them as shown.
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If you
don't want screw holes in the bottom of your finished project,
you can mount the turning stock to another block of wood;
then mount this block to the faceplate. Select a scrap block
at least 1" thick and about the same diameter as the faceplate
you'll be using. Find the center of this scrap block; then
glue the block to the turning stock, center-to-center. Put
a piece of paper (brown craft paper or grocery sack) in between
the block and the turning stock (Figure
12-40). Warning: Leave the pieces clamped for at least
24 hours prior to turning. Later on, this paper will make
it easier for you to part the scrap block from the turning.
After
the glue has set up com-pletely (at least 24 hours), mount
the scrap block to the faceplate with three #12 x 1-1/4" wood
screws. Warning: Be sure the screws penetrate into the
block at least 3/4". For large, bulky faceplate turnings
use longer screws and a thicker scrap block.
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Figure
12-41.
Mount the faceplate (with the scrap block and turning
stock attached) on the main spindle of the Mark V.
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Be sure
the speed dial is set on “Slow.” Then mount the
faceplate on the main spindle of the Mark V (Figure
12-41). Position the tool rest to turn the outside of
the workpiece first. When the tool rest is properly positioned
and the set-screws secured, turn the work-piece by hand to
make sure it doesn't scrape against the tool rest. Make a
four-point check. All four locks -power plant, carriage, tool
rest height, quill-should be secure. The speed should be set
at “Slow.” Turn on the Mark V and slowly turn the
speed dial to the recommended speed for the operation. The
stock should rotate smoothly, without excessive vibration.
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Figure
12-42.
Before rounding a faceplate turning, check which way
the wood grain runs. If the grain is perpendicular to
the axis of rotation, do not attempt to shear. Scrape
the workpiece round as shown.
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Rounding
Round the outside diameter first. Use a gouge, just as you
would for spindle turning, with this one exception: If the
wood grains are perpendicular to the axis of rotation, do
not attempt to shear. Scrape the workpiece round (Figure
12-42). Trying to shear will tear out large chunks of
the stock. Shearing only works well when the wood grain is
parallel to the axis of rotation.
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Figure
12-43.
Use dividers or a compass to mark concentric circles.
A light touch is in order.
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Sizing
After the workpiece has been rounded, it should be marked
to show the limits and the depth of shapes you wish to produce.
With the machine turned off, work with dividers or a pencil
compass to mark concentric circles (Figure
12-43), but be sure to use the tool rest for support.
Use a light touch. You can use a marking gauge to mark dimension
lines on the perimeter of the workpiece as shown in Figure
12-44.
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Figure
12-44.
A marking gauge can be used to mark dimension lines
on the perimeter of the workpiece.
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Shaping
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Figure
12-45.
Turn the outside of your workpiece first. Remember:
If the wood grain is perpendicular to the axis of rotation,
use a scraping action.
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Most woodworkers
prefer to turn the outside first (Figure
12-45). Make your beads and coves in the same manner as
you would for spindle turning. If the wood grain is perpendicular
to the axis of rotation, scrape the desired shape in the outside
of the workpiece.
When you
get ready to turn the inside of the workpiece, turn the machine
off. Let it come to a complete stop; then reposition the tool
rest at 900 to the axis of rotation, about 1/4" in front of
the workpiece. Adjust the height so that it's about 1/4" below
the center of the workpiece.
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Figure
12-46.
To shape the inside of a faceplate turning, position
the tool rest in front of the stock, just below the
center. Feed your chisels against the "down" side of
the workpiece. This will help hold the tool against
the tool rest. Click on image to see larger view.
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No matter
what the orientation of the wood grain, scraping is the only
way to shape the inside of a faceplate turning. This is slow
work, so have patience. Select a round nose chisel, turn on
the lathe, and slowly feed the chisel against the “down”
side of the stock (Figure
12-46).
When doing
deep hollowing jobs, keep adjusting the tool rest to provide
good chisel support even if it means partially inserting the
tool rest in the hollow being formed (Figure
12-47). As you continue the
hollowing
operation, periodically check the inside diameter of the turning
with “inside” calipers so that you don't scrape
away too much
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Figure
12-47.
Always place the tool rest so the chisel will have maximum
support even if on hollowing jobs it means inserting
the tool rest into the cavity being formed.
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stock
(Figure 12-48).
Stop scraping whenever you've removed as much stock as you
want to cut away. Figure
12-49 shows a gauge you can make to check the depth of
hollowing cuts. It's just a dowel that passes through a hole
in a “beam” and which is locked in place with a
setscrew. Cut depths can also be checked by placing a straightedge
across the face of the workpiece and then measuring from it
to the bottom of the cavity.
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Figure
12-48.
Use “inside” calipers to periodically check
the inside diameter of your turning so that you don't
scrape away too much stock.
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Figure
12-49.
You can make a simple gauge to check the depth of cut
on hollowing jobs.
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Figure
12-50.
A full-sized template can be used to mark dimension
points and to check the profile. Click on image to see
larger view.
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Templates,
like those described for spindle turnings, can also be made
for faceplate work (Figure
12-50). One side of the template is used to mark dimension
points, the other side has the checking profile that you use
to gauge the cuts you make. Templates are always a good idea
when you must turn duplicate pieces.
Sanding
When you've finished shaping the turning, turn off the machine
and let it come to a complete stop. Warning: Remove the
tool rest before sanding a turning on the lathe.
You can
remove the feathers either by wetting the wood or by removing
the faceplate from the main spindle and remounting it on the
upper auxiliary spindle (Figure
12-51). This reverses the direction of rotation.
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Figure
12-51.
Remounting the faceplate on the upper auxiliaiy spindle
reverses the direction of rotation so that you can sand
the "feathers" off the turning.
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Parting
To part a faceplate turning, first dismount the faceplate
from the Mark V spindle and unscrew the faceplate from the
scrap block. Clamp the scrap block in a vise and place a bench
chisel against the joint between the block and the turning
(where you've put the paper). Sharply rap the chisel with
a mallet, driving it in between the block and the turning
(Figure 12-52).
The turning will part from the scrap block. Sand any paper
or excess glue off the turning.
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Figure
12-52.
Part the turning from the scrap block by driving a bench
chisel in between the block and the turning.
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Continue
to Other Special Techniques
Back to Spindle Turning
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