Sherline 4400 Lathes - Assembly and Instruction Guide

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Guide to Approximate Turning Speeds
Material Cut Speed
S.F.M.
1/4" (6mm)
Diameter
1/2" (13mm)
Diameter
1" (25mm)
Diameter
Stainless, 303 67 1000 RPM 500 RPM 250 RPM
Stainless, 304 50 800 400 200
Stainless, 316 47 700 350 175
Steel, 12L14 174 2600 1300 650
Steel, 1018 87 1300 650 300
Steel, 4130 82 1250 650 300
Gray Cast Iron 57 900 450 220
Aluminum, 7075 400 2800 2800 1400
Aluminum, 6061 375 2800 2800 1400
Aluminum, 2024 268 2800 2000 1000
Brass 400 2800 2800 1400
Another tool available to Sherline
machinists that holds carbide
inserts is the 1/4"–3/8" two-
position rocker tool post, P/N 7603 (See Figure 47). This
tool post has slots on two opposite sides to hold both 1/4"
and 3/8" square shank tools individually or at the same time.
This allows you to switch quickly between tools of the two
dierent sizes simply by rotating the tool post. The 3/8" side
is designed to t the larger 3/8" square tool holders commonly
used for carbide or diamond inserted tips. Adding this tool
post to your arsenal will allow you to keep both your standard
1/4" high-speed steel tools set up for jobs where they are
sucient and also have a 3/8" carbide insert tool ready for
jobs where it is required.
Sherline also oers a ceramic insert and holder, P/N 2265. (See
Figure 48.) The 3/8" IC negative rake ceramic indexable holder
will bring a lot of enjoyment to your machining, particularly if
you choose to turn hard materials such as tool steel or abrasive
materials like berglass or composites.
When searching for a mirror-like nish on copper or aluminum,
diamond inserts are also available. Though expensive, certain
jobs can make their use desirable.
While inserted tip carbide, ceramic and diamond cutting tools
will improve the performance of the Sherline lathe, they will
not correct poor machining technique. Rigid setups are a must
for tools such as these.
Turning Speeds
The following chart in Figure 49 provides a guide to speeds
at which work of diering materials should be rotated. Note
that the turning speed is inversely proportional to the diameter
of the work; that is, the larger the diameter, the slower the
turning speed. Material often diers in hardness, so these
gures may have to be adjusted. The harder the material, the
slower the turning speed should be.
FIGURE 47—Two-Position Rocker
Tool Post (P/N 7603)
FIGURE 48—The P/N 2265
negative rake ceramic insert and
3/8" holder make it possible to cut
hardened tool steels.
Keep in mind that, apart from possible production of excessive
heat and the fact that excessive speed may damage the cutting
edge or cause it to “rub” instead of cutting, turning speeds are
not too critical. Slower than normal speeds cause no harm,
except by increasing the time involved. Aluminum, however,
usually gives a better nish turned at high speed and with the
use of lubrication (coolant).
Accessories for Your Lathe
Your lathe can be made more versatile with the addition of
suitable attachments and accessories. These include various
chucks and collets, a thread-cutting attachment, vertical
milling column, knurling tool, a live center and many others.
Remember that accessories and attachments must be cared for
in the same way as the lathe. Always make sure that threads
are free from metal chips and dirt. Chucks should be lightly
oiled frequently so that they continue to function smoothly
and accurately. Gears in the thread-cutting attachment should
be lightly greased when in operation. Some attachments have
moving slides, and these should be lubricated in the same
way as the slides in your lathe. Each accessory comes with
complete instructions for its use when it is purchased.
3-Jaw, 4-Jaw and Drill Chucks
Chucks are used to hold work in the lathe. They can also be
used to function like a vise to hold a part for milling. Drill
chucks can be used in the lathe headstock or tailstock or in
the mill for drilling. Here are some of the chucks available
for your Sherline tools:
Three-Jaw Self-Centering Chucks—Three jaws
scroll in unison to grip round or hex stock
The 2.5" chuck (P/N 1041) holds from
3/32" (2 mm) up to 1-3/16" (30 mm) in
diameter. Jaws are reversible for holding
larger stock up to 2-1/4" (56 mm) in
diameter. The chuck has a .687" (17 mm) through hole and
3/4-16 spindle thread. The larger 3.1" (70 mm) diameter P/N
1040 chuck is similar but holds parts up to 2-3/4" in diameter
with the jaws reversed.
Four-Jaw Self-Centering Chucks—These scrolling
chucks hold round or square stock. The
2.5" diameter P/N 1075 version holds
from 3/32" (2 mm) up to 1-3/16" (30 mm).
With the jaws reversed, it will grip stock
up to 2-1/4" (56 mm). The jaws scroll in
unison as on the 3-jaw chuck. (NOTE:
stock held in this chuck must be perfectly
round or square to be gripped by all four jaws.) The larger
3.1" diameter version of this chuck is P/N 1076, which can
hold parts up to 2-3/4" in diameter with the jaws reversed.
Four-Jaw (Independent) Chucks—Each jaw is
adjusted independently, allowing precise
adjustment for perfect centering or for
holding odd-shaped parts. Four-jaw
chucks take a little more time to use, but
oer much greater accuracy and versatility
than a 3-jaw chuck. Holding range is the
same as for the 2.5" and 3.1" 3-jaw chucks above. The 2.5"
4-Jaw is P/N 1044 and the 3.1" 4-Jaw is P/N 1030.
Jacobs Drill Chucks—Various size conventional Jacobs drill chucks
FIGURE 49—High-speed steel cutting tool turning speeds
New Sherline Accessories
Sherline introduces new accessories every year. See our
website for new product introductions.
sherline.com/whats-new/