AmericanWoodworker-ToolTest-WorkshopLathesJan2003.pdf

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Tool Test:
By Tim Johnson
and Alan Lacer
Workshop
Workshop
There’s one
for every
budget
Lathes
Lathes
ART DIRECTION: VERN JOHNSON • PHOTOGRAPHY: MIKE HABERMANN, UNLESS OTHERWISE INDICATED
88
A m e r i c a n Wo o d w o r k e r
JANUARY 2003
sk anyone who’s seen the
ribbons of shavings fly—
turning wood is compelling.
Transforming a spinning hunk
of rough wood into an object of
beauty has such enormous
appeal; everybody wants to try it.
For versatility, nothing beats a
general-purpose lathe (Photos 1
and 2). In addition to bowls and
plates, a general-purpose lathe
can also turn table legs, bedposts
and other furniture parts. It can
even handle small turnings, like
goblets, pens and tiny toy tops.
Spindles (long, slender pieces,
such as pens, chair parts and table
legs) are turned between the
headstock and tailstock centers.
Bowls and plates are mounted on
a faceplate, which threads onto
the headstock spindle.
A
DRIVE
SPINDLE
TOOL-REST
ASSEMBLY
TAILSTOCK
GAP
HEADSTOCK
CABINET-
STYLE
BASE
A TRADITIONAL-STYLE LATHE has a
fixed head that supports the drive spindle
and a narrow cabinet-style base that houses
the motor.The tool-rest assembly and tailstock
slide and lock on the cast-iron bed.The gap
allows turning slightly larger diameters of thin
stock over the bed. Large-diameter bowls
mount on the outboard side of the head.
1
MOVEABLE
HEADSTOCK
CONTINUOUS
BED
A Lathe Can Be
a Big Investment
2
We tested 18 general-purpose lathes,
ranging in price from $260 to $1,350.
You can pay a lot more (see You Should
Also Know About, page 97), but the
machines we tested should fit the bill for
both serious amateur woodworkers and
small professional shops, where the
lathe isn’t used constantly.
All of the lathes we tested have at
least 12-in. capacity for bowls and
enough spindle capacity to handle a
dining table leg.
Most of these machines come sup-
plied with bolt-together leg sets or
stands. Machines with cabinet-style
bases usually come fully assembled. In
a few cases (noted in the chart on page
96), the stand is an additional-cost
option.
For testing, we divided the lathes
into two price categories: more than
$800 and less than $800.
BIG
FOOTPRINT
THE NEWEST
LATHES feature
headstocks that slide
or pivot, gapless beds,
well-located controls,
motors mounted near
the drive spindle and
widely splayed legs.
3
A BIG BOWL
BLANK
requires a heavily built
lathe. Every lathe we
tested has the
capacity to mount a
large-diameter bowl
blank, but not all
of them can
handle the force
that blank generates
when it spins.
SOLIDLY BUILT
HEADSTOCK
BIG
MOTOR
ROBUST
TAILSTOCK
MASSIVE
BED
A m e r i c a n Wo o d w o r k e r
JANUARY 2003
89
Tool Test
Bowl Turning: The Acid Test
SPEED-
CHANGE
LEVER
EXPANDING
PULLEYS
MECHANICAL
VARIABLE SPEED SYSTEMS make it very easy to change speeds on the fly.
Moving the speed-change lever causes the inside diameter of one pulley to expand
while the other contracts.The change in diameters changes the spindle speed.
4
STEP PULLEY
SPINDLE
Just about any lathe is adequate for spin-
dle work, small bowls (less than 6-in.
diameter), thin plates and platters.
Larger bowls, however, push many of
these lathes to their limits (Photo 3).We
found that turning 12-in.-diameter
rough green-wood bowl blanks was the
acid test. Here’s why:
• Green wood is heavy, because it’s full
of water. The lathe must be built heav-
ily enough to withstand the force gen-
erated by a massive spinning blank.
• Rough-cut blanks are unbalanced and
out of round.A heavy, unbalanced piece
can cause destructive vibration on a
lathe that lacks stability.
• The blank’s edge speed (the rate at
which its outer edge travels) increases
with its diameter. To maintain a safe
edge speed with a 12-in. bowl, the lathe
needs to have slow low-end speeds.
Must-Have Features
DRIVE
BELT
BELT-TENSION
LEVER
Green-wood bowl turning has become
enormously popular, for several rea-
sons. The wood is free, it cuts like warm
butter, and a wide variety of interesting
material is just waiting to be found.
For bowl-turning, the bottom line
is a lathe’s ability to spin a rough-cut,
unbalanced blank safely.A capable lathe
must turn at very slow speeds and be
equipped with a motor that generates
sufficient torque. It must have enough
mass to dampen significant vibration
and the tool rest and tailstock must be
rock-solid.
Slow Low-End Speed
5
STEP-PULLEY DRIVE SYSTEMS are simple, reliable and efficient, but you have
to stop the lathe to change speeds.The number of steps on the pulleys
corresponds with the number of speeds.
Fig.A Motor Size
A big motor is better because it delivers more power for turning at slow speed.
1/2 HP
Craftsman 21712
Grizzly G5979
Grizzly G1067Z
Record CL1-36
Ridgid WL1200
Yorkcraft YC-900WL
3/4 HP
Central Machinery 34706
Delta 46-715
General 160-1-M1
Grizzly G1495
JET JWL-1236
Record CL 3-48
Woodtek 829806
1 HP
Craftsman 21715
JET JWL-1442
Nova 3000
Vega 1446
Woodfast C1000
Lathes operate over a range of several
speeds, to accommodate different size
turnings. In general, as the diameter of
the blank increases, the appropriate
speed decreases.
The key factor is the blank’s edge
speed. Edge speed increases with diam-
eter; the further the blank’s outer edge
is from the center, the faster it rotates.At
the same spindle speed, the edge of a
12-in.-diameter bowl blank travels
over
20 times faster
than a 1/2-in.-diameter
pen blank. For large-diameter bowl
turning, slow low-end speed is a must.
90
A m e r i c a n Wo o d w o r k e r
JANUARY 2003
Workshop Lathes
For pen making, it’s just the
opposite.
A safe operating speed
depends on the size of the
blank and the stability of the
lathe. For big, out-of-round
bowls, slower is definitely
better. Many of the
lathes we tested don’t
have the combination
of slow speed and sta-
bility to safely handle
heavy 12-in. green-
wood bowl blanks.
Speed Changes
For speed changes, most
of the lathes we tested are
equipped with mechanical-
variable-speed systems
(Photo 4). Mechanical
systems are user
friendly, but they rob
a bit of the motor’s
power and you can
only
change speeds
while the lathe is running. This
can create a dangerous situation, if you
haven’t slowed the speed down all the
way before mounting a big bowl blank.
We found the slowest low-end speeds
on step-pulley-equipped lathes (Photo
5).With this manual speed-change sys-
tem, you have to stop the machine and
move the belt. Repositioning the belt
can be difficult if there’s not enough
room for your fingers.
Power
SHELF-
FLANGE
6
WEIGHT IS GOOD.
Robust, cast-iron machines have two
important attributes for turning.They’re heavy and
they absorb vibration.The Jet 1442’s cast-iron legs are the best of this
category.They provide a wide stance and a low center of gravity.They
also include flanges for a shelf, so you can add even more weight.
Stabilize a lightweight lathe
The motor has to develop sufficient
torque to keep the bowl rotating while
you cut. For power at slow speed, a big-
ger motor is better. Small motors just
don’t generate enough torque.
Lathes equipped with 1-hp motors
were the most capable (Fig. A). Three-
quarter-hp motors were adequate, but
more likely to bog down with a heavy
cut.You may have to tailor your cutting
rate to the lathe’s ability to keep up.
One-half-hp motors lack sufficient
power. They’re okay for spindles, but
they stop too easily or spin too fast for
big bowl blanks.
WELL-SEALED
SAND BAGS
7
IMPROVE ANY LIGHTWEIGHT LATHE for bowl turning by adding
ballast.Add a shelf and load it with bags of sand sealed in plastic. Ballast
absorbs vibration and lowers the lathe’s center of gravity.
A m e r i c a n Wo o d w o r k e r
JANUARY 2003
91
Tool Test
QUILL LOCK LEVER
Stability
QUILL
CENTER
TAILSTOCK
QUILL
ALIGNMENT
KEYWAY
WIDE
BED
TOOL-REST
BANJO
TOOL
REST
For stability, a lathe needs mass, a wide
footprint and a low center of gravity.
Look for heavy cast-iron components
(Photo 6) and a base with provisions for
a low shelf, so you can add ballast.
Cabinet-style bases (Photo 1) have a
narrow footprint that makes the lathe
tippy for bowl turning. Bolt-on
legs (Photo 2) splay for stability, but
their lightweight structure amplifies
vibration.
Adding ballast to a low shelf
improves the stability of any lathe, by
absorbing vibration and lowering its
center of gravity. Sand, sealed in plastic
bags so it won’t leak, makes great ballast
(Photo 7).
Rock-Solid Tailstock and Tool Rest
LOCK LEVERS
8
A TOOL-REST ASSEMBLY AND TAILSTOCK that adjust easily, and
lock positively are essential. Substantial castings and a wide bed
provide rock-solid support. Look for a long tool-rest banjo, a massive tool
rest, long lock levers that are adequately spaced to prevent pinch points,
and a tailstock quill with separate accommodations for
alignment and locking.
GAP
CONTINUOUS
BED
9
92
A CONTINUOUS BED allows you to position the tool rest
behind a bowl blank, as well as in front of it, so you can work
both surfaces without remounting the bowl. Delicate, thin-walled bowls
are possible, because the inner and outer surfaces will be perfectly
concentric.A gap in the bed (inset) limits the tool rest’s location.
A m e r i c a n Wo o d w o r k e r
JANUARY 2003
Loosening or movement of the tail-
stock or tool-rest assembly during oper-
ation can be hazardous, so these parts
must lock positively (Photo 8).
A good tool-rest assembly is essential.
It’s always at the center of the cutting
action and it gets handled more often
than any other part of a lathe. Uncom-
fortable, hard-to-use lock levers are a
real nuisance.The tool rest should be
heavily made. A long banjo (over 11
in.) extends the tool rest’s reach, a must-
have for bowl turning.
On most of the lathes we tested, the
tool rest and banjo are merely ade-
quate. Secure locking is difficult,
because the lock levers are either too
short, too thin, or too close together.
Unsatisfactory lock levers for the tool
rest are most common. Even lathes
equipped with decent levers on the
banjo employ crummy ones to lock the
tool rest.
Many of the smaller lathes came with
extension arms that mount in the
banjo(photo, lower left, page 94).
They’re intended to increase the reach
of the tool rest for outboard turning,
but they aren’t very useful.A long banjo
is much better.
The tailstock houses and supports
the tailstock quill, which holds the
lathe’s second center. For accuracy, this
center should align with the drive

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