I Can’t Sleep - Woodturning | Gentle Bedtime Reading for Sleep
Episode Date: June 5, 2023Unwind with this calm bedtime reading as Benjamin explores the craft of woodturning, helping you relax and ease insomnia. You’ll learn how artisans have shaped wood on lathes for centuries, creating... everything from bowls to decorative art. Benjamin’s soothing cadence transforms technical details and history into peaceful storytelling that reduces stress and quiets the mind. This isn’t whispering or hypnosis—just gentle, fact-filled narration designed to guide you into rest. Press play, settle in, and let this exploration of the timeless art of woodturning carry you into a deep and restful sleep. Want More? Request a Topic: https://www.icantsleeppodcast.com/request-a-topic Ad-Free Episodes: https://icantsleep.supportingcast.fm/ Shop Sleep-Friendly Products: https://www.icantsleeppodcast.com/sponsors Join the Discussion on Discord: https://discord.gg/myhGhVUhn7 This content is derived from the Wikipedia article on Woodturning, available under the Creative Commons Attribution-ShareAlike (CC BY-SA) license. Read the full article: Wikipedia – Woodturning. Happy sleeping! Learn more about your ad choices. Visit megaphone.fm/adchoices
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Today's episode is from a Wikipedia article titled Woodturning.
Wood-turning is the craft of using a wood-lath with handheld tools
to cut a shape that is symmetrical around the axis of rotation.
Like the potter's wheel, the wood lathe is a mechanism that can generate a variety of forms.
The operator is known as a turner,
and the skills needed to use the tools were traditionally known as turnery.
In pre-industrial England, these skills were
sufficiently difficult to be known as the mysteries of the Turner's Guild.
The skills to use the tools by hand without a fixed point of contact with the wood,
distinguish wood turning and the wood lathe from the machinist lathe, or metal working lathe.
Items made on the lathe include tool handles, candlesticks, egg cups, knobs, lamps,
rolling pins, cylindrical boxes, Christmas,
ornaments, bodkins, knitting needles, needle cases, thimbles, pens, chestmen, spinning tops,
legs, spindles, and pegs for furniture, balusters and newel posts for architecture,
baseball bats, hollow forms such as woodwind musical instruments, urns, sculptures,
bowls, platters, and chair seats.
Industrial production has replaced many of these products from the traditional turning shop.
However, the wood lathe is still used for decentralized production of limited or custom turnings.
A skilled turner can produce a wide variety of objects with five or six simple tools.
The tools can be reshaped easily for the task at hand.
In many parts of the world, the lathe has been a portable tool that goes to the source of the wood,
or adapts to temporary workspaces.
21st century turners restore furniture,
continue folk art traditions,
produce custom architectural work,
and create fine crafts for galleries.
Wood-turning appeals to people who like to work with their hands,
find pleasure and problem-solving,
or enjoy the tactile and visual qualities of wood.
Wood lathes work with either reciprocating or continuous,
revolution. The reciprocating lathe is powered by a bow or a spring, rotating the wood first in one direction,
and then in the other. The Turner cuts on just one side of the rotation as with the pole lathe.
The reciprocating lays may be human powered with a bow as well as with spring mechanisms.
The reciprocating lays, while primitive technology requiring considerable dexterity to operate,
is capable of excellent results in skilled hands.
For example, reciprocating bow lathes are still used to turn beads for the Arabian lattice windows,
called Meshrebbeye that so charmed Holtzopful in the 1880s.
Continuous revolution of the workpiece can be human-powered with a treetle wheel,
or achieved with water, steam, or electric power.
The style of cutting does not have the pause required by the reciprocating lays rotation.
Even with continuous revolution, however, the turner controls the contact of tools and wood entirely by hand.
The cutters are not fixed nor advanced automatically, as with the metal working lathe.
The nature of wood defines wood-turning techniques.
The orientation of the wood grain relative to the axis of the lathe,
affects the tools and techniques used by the wood turner.
In spindle turning, the grain runs lengthwise along the lathe bed,
as if a log were mounted in the lathe.
Grain is thus always perpendicular to the direction of rotation under the tool.
In bull turning, the grain runs at right angles to the axis,
as if a plank were mounted across the chuck.
When a bowl blank rotates, the angle that the grain makes with the cutting tool
continually changes between the easy cuts to two places per rotation,
where the tool is cutting across the grain and even upwards across it.
This varying grain angle limits some of the tools that may be used
and require additional skill from the turner.
Moisture content affects both the ease of cutting wood
and the final shape of the work when it dries.
Wetter wood cuts easily with a continuous ribbon of relatively dust-free shavings.
However, the wet wood moves as it dries, shrinking less along the grain.
These variable changes may add the illusion of an oval bowl,
or draw attention to the features of the wood.
Dry wood is necessary for turnings that require precision,
as in the fit of a lid to a box,
or in forms where pieces are glued together.
The character of the wood creates other challenges for the wood turner.
Turners of hardwoods and ivory select different tools than those used for cutting softwoods.
Voids in the wood require higher lathe speeds, fillers, or extra safety precautions.
Although other woodworkers value tight, straight grain, woodturners often search out the unusual wood from roots, defects, or diseased portions of trees.
The crafting of wood turning is preserved and advanced by a cum laude.
community of practitioners. Until the 1970s, an apprentice system in the UK and industrial arts
education in the U.S. preserved many of the traditional skills of the craft. Between 1975 and
1985, industrial arts teachers, hobbyists, artists, collectors, and tool suppliers developed the
symposium format for the exchange of information about the craft. This community was the
kind of prototype for the artisan-based maker culture active in the 21st century.
The community organizes regional, national, and international symposiums,
published journals, and hosts traveling experts at club events.
Most publications and DVDs are of the DIY variety, including numerous YouTube videos.
The archaeological record of wood turning is limited to illustrations because wood is
is a fiber-prone to rot.
Egyptian monuments illustrate a strap used by a helper
to rotate the lathe while another worker cut the wood.
Early bow lathes and strap lathes were developed and used in Egypt and Rome.
The Chinese, Persians, and Arabs had their variations of the bow-lath.
Early lath workers would sometimes use their bare feet to hold cutting tools in place
while using their hands to power the lathe.
Bow lathes continue in use right up to the present day,
and much of our information about them comes from watching turners use them.
Between 500 and 1,500 AD,
turned wood vessels served as the everyday bulls and cubs of most of the population of Europe.
Our knowledge of these humble vessels comes from bulls excavated from shipwrecks,
such as the Mary Rose and the Osberg Burial Ship, or dug out of deep wells, where they were preserved in an anaerobic environment.
Much of this wear was turned from green wood on a spring pole lathe.
Finally crafted drinking bowls, known as mazes, were produced in very limited quantities from drywood,
then decorated with silver gilt central bosses and rims.
As early as 1568, a separate flywheel powered a lathe via a drive belt.
A master would cut the wood, while an apprentice turned the crank on a huge wheel, often several feet in diameter.
This was a continuous revolution lathe which led to adaptation to external power sources such as water, steam, and electricity.
This lathe evolved into the queen of machine tools, which made it possible to turn to the water,
parts for other machinery. The Holtzopfuls developed ornamental turning
laves from the continuous revolution lathe, combined with metal-working
innovations like the automatic slide rest. These lathe's worked from geared patterns to
cut designs in hardwoods such as ebony. They were favored as a hobby by European
princes, meriting a mention by Tolstoy in War and Peace, 1869. Wood turners in London
organized into a guild as early as 1310 on Wood Street. By 1347, the Turner's Company was assigned
responsibility for regulating weights and measures by the mayor. By 1591, they built their own
hall. The company governed the apprentice system and established pricing for goods. In 1604,
they were incorporated as the worshipful company of Turner's of London. Outside of London, the craft
was decentralized and unregulated.
Itinerant turners, known as bodgers,
set up temporary pole lathes near the source of wood
for turning furniture parts.
In the 19th and early 20th century,
wood turners in England worked in turning shops,
usually within the master-apprentice system.
In Germany and Russia,
wood-turning was concentrated in villages
that had a specialty such as turning toys.
Bow lathes and pole lathes continue in use for decentralized one-man production of architectural elements and bowls in many parts of the world.
In the U.S. Woodturning was part of the curriculum of industrial arts taught in public schools, often a prerequisite for classes in building furniture.
The problems from textbooks included both tool management skills and assignments to turn objects such as gavels, darning eggs, box.
trays, candlesticks, lamps, and legs for furniture.
Wood-turning skills were used by pattern makers
in the making of prototypes and shapes for casting molds,
used in foundries during the 19th and 20th centuries.
They worked very slowly to achieve precision,
using enormous pattern-maker lathes and slow-cutting scraping tools.
Wood-turning has always had a strong hobbyist presence.
In the 1970s, an explosion of interest in hobby woodturning in the English middle-speaking world
sparked a revival in the craft.
Dr. Dale Nish traveled to England to recruit teachers, tools, and techniques from the last of the apprentice-trained woodturners.
A few years later, Canadian Stephen Hogburn spent a year in Australia,
pushing the limits of the craft through changes in scale and design.
Industrial arts teachers used their institutional affiliation to create seminars, published books, and foster research.
The tool industry identified a new market for lathes and turning tools.
A small group of serious collectors invested in the increasingly sculptural explorations of wood turners.
And usually, wood turning never established a strong foothold in university departments of art and design.
Instead, practitioners of the craft have become adept at learning from demonstrations,
private classes, regional meetings, their own published journals, and internet technologies.
Some artists began as wood turners and moved into more sculptural work,
experimenting with super object forms and other fine craft concepts.
The Center for Art and Wood founded in 1986 as the Wood Turning Center,
houses a collection in Philadelphia with over 1,000 objects from international artists,
as well as a research library and gallery.
Other turners have chosen an artisan-based focus on traditional work,
custom work, and the pleasure of studio practice.
Complex forms made on a wood lathe developed from surprisingly few types of cuts,
parting, planing, bead, cove, and hollowing.
Parting separates the wood from the holding device or establishes depth cuts.
Planning is done with a tool in which the bevel below the cutting edge supports wood fibers,
such as in a typical wood planar.
Beads are a convex shape relative to the cylinder, and coves are a concave shape.
Hollowing techniques are a combination of drilling and scoping out materials.
The wood turner is at liberty to choose from a variety of tools for all of these techniques,
and the quality of the cuts improves with practice wielding the tool selected.
Turners rely upon three points of contact, making any type of cut.
The tool presses down on the tool rest and against the wood turner's body before contacting the surface of the wood,
most often with a bevel edge riding the surface of the wood.
The objective is to position the tool correctly so that the wood comes around to the cutting edge,
generating a thin shaving without chipping or tearing out sections of the wood.
Wood turners prefer to use very clean cuts to minimize the time spent with abrasives.
When it is necessary to sand the piece, they do so on the lathe,
using abrasives held by a hand in an inertial sander that revolves with the wood's rotation.
or with power tools, drills or right-angle drills.
The lathe also becomes a useful holding device for carving, burning,
texturing, coloring, and finishing the form.
The wood rotates between the headstock of the lathe,
which includes the drive mechanism,
and the tailstock support,
which only rotates if its center is live or supported by a rotating holding device.
The headstock end may use points or spur,
which are driven into the wood.
This type of turning is described as between centers.
The headstock spindle may also use a cup,
call it, or scroll chuck to hold a tendon on the workpiece
which will be removed in the finished product.
The wood can also be screwed or glued to a faceplate,
a strong disc that is threaded to mount on the headstock spindle.
The use of a chuck or faceplate allows the wood turner to forego tail stock
support for the rotating wood. This type of secure holding system is essential for hollowing
bowls or hollow forms. Turning tools are generally made from carbon steel, high-speed steel,
HSS, and more recently tungsten carbide. Comparing the three types, high-speed steel tools maintain
their edge longer, requiring less frequent sharpening than carbon steel, but not as long as tungsten
carbide.
Tungsten carbide tools typically consist of scraping tools with a disposable carbide insert attached
to the tool.
The harder the type of high-speed steel used, the longer the edge will maintain sharpness.
Tungsten carbide inserts are generally thought of as disposable, but they can be sharpened with
diamond abrasives.
Modern cutting and scraping tools can also be coated with titanium nitride to improve where
characteristics. Wood-turning tools must be sharpened more frequently than other edge-working
tools to maintain a clean cut because the wood passes at great speed. Sharpening is usually
accomplished with the aid of mechanical devices such as powered sharpening wheels and abrasives. This
sharpening process requires either skill of the craftsman or one of the many available
sharpening jigs which facilitate maintaining a specific bevel on the tool. As with any mechanical
sharpening method, overheating or bluing is a danger to be avoided as it will ruin the steel's temper,
rendering the steel too soft to maintain a sharp edge. When this happens, the blued area must
then be ground away to expose fresh steel, and the tool must then have the bevel re-established
and the edge re-honed. High-speed steel.
is not prone to bluing, overheating, whereas carbon steel blues easily, requiring frequent quenching
in water or oil to avoid losing temper. Spindle roughing gouge. A wide-fluted gouge used to
initially round a wooden spindle and to roughly shape it. Generally not intended for cutting end grain
due to the large cut it takes and the relatively weak tang connecting the blade to the handle,
unsaved for making bowls or any faceplate work.
Spindle gouge or detail gouge.
A shallow fluted gouge used to create details on spindles, including beads,
raised portions of the turning typically semi-circular and cross-section,
and coves relieved portions of the turning.
Bull gouge.
A deep-fluted gouge used to turn the outside and inside of bulls and velds,
vessels. Often has a thicker shaft and longer handle than a spindle gouge because it has to cut
farther away from the tool rest and deal with the forces of turning a large bowl, sometimes
called long and strong gouge. Skew chisel. A wide, steeply pointed chisel with the edge
running at an angle to the length of the tool. Used to smooth flat spindles, cut beads, and add details.
skew chisels are only used on spindlework, never on facework,
and are honed after sharpening to create a razor edge.
The skew is said to be the most difficult wood-turning tool to master,
but when used correctly it delivers a superb finish,
which is hard to match by any other tool.
Parting Tool
A pointed tool used to separate part-off work from the lathe
and to create a straight edge separating large and small diameter sections.
Wide parting tools are also called beddens are used to create evenly sized spindle sections.
Bedden tool.
Somewhere between a skew chisel and a parting tool.
Typically a piece of square stock with a 40-degree bevel at the end.
Only one face is ground and the tool is presented to the work with the side facing up.
It has a wider cutting edge than a parting tool that can be used as such.
It can also be used to roll beads and make peeling cuts similar to the skew.
Hollowing tool.
Many different types of tools are used to cut out the deep sections of steep bowls, vases, and hollow vessels.
Often with very long handles to maintain enough leverage when working in a deep vessel far away from the hand.
hand-dress.
Scraper.
A tool that scrapes the wood fibers instead of cutting.
These are used to smooth off wooden items cut with other tools, and to shape items that
are not possible or difficult to shape with gouges.
A sharp scraper has a burr at the edge which cuts the wood, only a dull scraper scrapes.
Bowl saver.
A tool used to core out the inside part of a bowl, allowing the waste pieces to be
be used to create a smaller bowl, and to limit the number of wood chips created when hollowing
out a bowl.
Auger, a drill bit used to drill a hole partway or through a wooden item for cutting the hole
for a lamp cord or as the first step when hollowing out a bowl or vessel.
Chatter tool.
A flexible scraper used to add decorative chatter marks to turned items.
wire
A simple wire
sometimes with handles attached at either side
to burn lines into the piece with friction.
There are also several tool types for special purposes,
as well as tools that are a combination design of the above tools,
i.e. skew-chisel combinations,
thread-cutting tools, ring-cutting tools,
medium-fluted couches, etc.
Eccentric turning.
Turning a single-piece,
multiple times upon different axes each time.
Oval or elliptical turning,
turning a piece using an accessory mounted to the headstock
that changes the center of rotation of the piece in time with a rotation
so that a cutting tool held in a fixed position on the tool rest
cuts an oval rather than a round path on the workpiece.
Sculpture turnery
Turning on a lathe that will generate turned work that is not necessarily circular
can be any of the following crosses.
Sections.
Elliptical, triangular, square, pentagonal, hexagonal, or heptagonal.
Multidimensional wood turning requires that the workpieces as it rotates
will be able to move cyclically along the lathe bed and or simultaneously move cyclically across the bed.
Three-dimensional wood-turning is where the shape produced by the lathe is not symmetrical about the axis of rotation.
Therming, mounting a carrier between centers and then mounting the small workpieces to the carrier,
so that the axis of the headstock, tail stock, does not pass through any of the workpieces,
and each workpiece gets cut only on one face.
As noted in
Wood-Turning Methods by Mike Darlow,
the etymology of the term thermal
comes via a corruption of the name of the Greek god Hermes,
who was often represented as a statue
set atop a plinth with the construction characteristic of themed work.
Segmented Turning
A method of turning where the wood blank
is constructed from many individual pieces of wood segments,
which are glued together before being turned.
Many interesting patterns can be generated through the process of gluing and shaping the lathe.
Green or wet turning.
Turning wood while its moisture content is above equilibrium,
often done when wood is newly felled.
May be turned to finished thickness,
in which case the differential shrinkage of the wood will result in a finish piece that is not perfectly round.
Alternatively, it may be rough turned.
Rough turning involves turning the piece only to its general shape,
leaving enough thickness so that after turning,
it can be allowed to dry to equilibrium moisture content and distort.
The advantage over first drying the wood and then turning
is that a rough turn piece tries faster,
will probably distort instead of split as solid wood tends to,
and that wet wood turns better since it creates less rust.
Rough turning is an inexact science.
Turning wood too sick will lead to splits,
and turning wood too sin will lead to distortion that cannot be removed
because not enough thickness is left.
Once try, it is mounted on the lathe a second time and turn to its final form.
Rough turning is typically used on most functional work
and some are pieces.
Natural edge work pieces that include the outside of the tree trunk or limb as the edge of the piece.
Typically artist's turnings, usually bulls or hollow vessels, and usually green turned to final dimension.
May include the bark or not, but pieces with bark should not have any bark damaged or missing.
Ornamental turning, also known as OT, a method in which the piece is
mounted upon a rocking headstock, and a spinning tool is used to cut out exotic and decorative
patterns. This device is called a rose engine lathe. Twistwork, a type of carving on spindles or vessels
in which the lathe is a holding device and the turner makes spiral cuts. The turner may use a grid
drawn on the wood or cut entirely by eye using either hand tools, power tools, or barricet
When wood turning, it is important to wear certain personal protective equipment, P.P.E. When working with spinning objects, loose clothing should not be worn. All jewelry should be removed, and long hair should be tied back. Since loose rags may also transfer color to the piece, paper towels should be used to avoid snags and accidents. Wood shavings generated during turning will need to be periodically removed.
Eye protection is a necessity when wood turning.
There are several types of PPE available for eye protection, such as safety goggles, glasses, and visors.
Although all of these are adequate, a visor that protects the entire head from dust and debris provides the highest level of protection.
Respiratory equipment and dust collection systems are also important when woodturning, or doing any type of woodworking that creates dust.
dust. This can range from a simple disposable dust mask to a full-face helmet with a built-in
respirator. Most standalone respiratory equipment will interfere with dust shields and visors,
so devices that incorporate both are ideal. Many kinds of wood create dust that is a health
hazard. For example, Cocoa Bolo Granadillo dust can cause toxic shock. Many people are sensitive
to soils carried in walnut, locust and oak sawdust.
Long-term exposure to fine wood dust has also been linked to an increased risk of developing cancer.
A lathe is a quiet machine compared to other power tools, but earplugs should be worn if
noise is excessive. This may be due to motor fan noise from a shop dust collector, or the
combination of wood and tool being used. Gloves should not be used with rotating equipment.
due to the risk of getting tangled in the machine.
However, wood can cause splinters that not only puncture the skin,
but also cause festering sores or skin irritation.
The polishes and finishes used in wood turning often contain organic solvents,
such as methanol, turpentine, and tollowing,
all of which can be harmful irritants to the skin.
This subject continues to be debated in the community.
protective footwear such as leather steel-toe boots is essential for any type of shop activity.
A good way to check the safety before starting the lathe is safer.
S. Speed.
The rotational speed should be slower for big, heavy items and faster for smaller, lighter things.
Most craftsmen recommend starting at slow speeds and resetting speed to low at the end of the session.
A. A. A side. Stand to the side of the blanks fire in line, not in front of the wood. F. Fixings
Confirm that all materials and equipment, tool rest, tail stock, etc. are correctly attached and secured.
E. I. and ear protection. Where sufficient eye and ear protection.
R. Revolve. Confirm the wood can freely rotate without encountering any obstructions.
such as the tool rest. Safe usage of a lathe also depends on the operator's choice of proper techniques
for the lathe tools and wood. For example, using a high spindle speed with an unbalanced wooden
blank may cause the lathe to vibrate dangerously. Spinning a large turning blank too quickly
may cause it to explode. Inappropriate use of tools such as gauges and skew chisels can cause a catch.
where the tool bites suddenly and aggressively into the wood in an uncontrolled manner.
These risky practices can exert extremely large forces upon the wood, the tool, the lathe, and the operator.
The wood could fracture or tear free from the lathe.
In lathe accidents, tools are often torn from the operator's hand and thrown in unexpected directions.
Particular care is required for wooden shapes that are not circular, such as off-center work,
and for bowls with wings or sharp rims.
Portions of the turning extend farther from the axis of rotation
and are sometimes more difficult to see than the bulk of the wooden blank.
Turning is a machining process in which a cutting tool,
typically a non-rotory tool bit,
describes a helix tool path by moving more or less linearly
while the workpiece rotates.
Using the term turning is reserved for the genera,
of external surfaces by this cutting action, whereas this same essential cutting action,
when applied to internal surfaces, holes of one kind or another, is called boring.
Thus the phrase turning and boring categorizes the larger family of processes known as
lathing. The cutting of faces on the workpiece, whether with a turning or boring tool,
is called facing, and may be lumped into either category as a same.
subset. Turning can be done manually in a traditional form of lathe, which frequently requires continuous
supervision by the operator, or by using an automated lathe which does not. Today the most common type of
such automation is computer numerical control, better known as CNC. CNC is also commonly used with many
other types of machining besides turning. When turning, the workpiece, a piece of relatively rigid
material, such as wood, metal, plastic, or stone, is rotated and a cutting tool is traversed along
one, two, or three axes of motion to produce precise diameters and depths. Turning can be either
on the outside of the cylinder or on the inside, also known as boring, to produce the
tubular components to various geometries. Although now quite rare early
lathes could even be used to produce complex geometric figures, even the platonic
solids. Although since the advent of CNC it has become unusual to use non-computerized
toolpath control for this purpose. The turning processes are typically
carried out on a lathe, considered to be the oldest of machine tools,
and can be of different types such as straight turning, taper turning, profiling, or external grooving.
Those types of turning processes can produce various shapes of materials such as straight, conical, curved, or grooved workpieces.
In general, turning uses simple, single-point cutting tools.
Each group of workpiece materials has an optimum set of tool angles that have been developed through the years.
The bits of waste metal from turning operations are known as chips, North America, or Swarf, Britain.
In some areas, they may be known as turnings.
The tools axes of movement may be literally or straight line, or they may be along some set of curves or angles,
but they are essentially linear in the non-mathematical sense.
A component that is subject to turning operations can be turned.
as a turned part or machine component.
Turning operations are carried out on a lathe machine which can be manually or CNC operated.
Turning specific operations include turning.
The general process of turning involves rotating apart,
while a single point cutting tool is moved parallel to the axis of rotation.
Turning can be done on the external surface of the part, as well as the internal surface,
surface. The starting material is generally a workpiece generated by other processes such as casting,
forging, extrusion, or drawing. Tapered turning produces a cylindrical shape that gradually decreases
in diameter from one end to the other. This can be achieved, A, from compound slide,
B, from taper turning attachment, C, using a hydraulic copy attachment, D, using a CNC,
lathe, E, using a form tool, F, by the offsetting of the tailstock, this method more suited
for shallow tapers.
Spherical generation produces a spherical finished surface by turning a form around a fixed axis
of revolution.
Methods include A, using hydraulic copy attachment, B, C&C, computerized numerically controlled lathe,
C, using a form tool, a rough and ready method.
D, using bed jig.
Heart turning is a type of turning done on materials with a Rockwell C hardness greater than 45.
It is typically performed after the workpiece is heat treated.
The process is intended to replace or limit traditional grinding operations.
Hard turning, when applied for purely stock removal purposes,
competes favorably with rough grinding.
However, when it is applied for finishing
where form and dimension are critical,
grinding is superior.
Grinding produces higher dimensional accuracy
of roundness and cylindricity.
In addition,
polished surface finishes of RZ equals 0.3
to 0.8Z
cannot be achieved with hard turning alone.
Hard turning is appropriate for parts
requiring a roundness accuracy of 0.5 to 12 micrometers,
and or surface roughness of RZ.8 to 7 micrometers.
It is used for gears, injection pump components,
and hydraulic components, among other applications.
Facing in the context of turning work involves moving the cutting tool at right angles
to the axis of rotation of the rotating workpiece.
This can be performed by the operation of the cross-slide,
if one is fitted, as distinct from the longitudinal feed turning.
It is frequently the first operation performed in the production of the workpiece,
and often the last, hence the phrase, ending up.
This process also called parting off or cutoff,
is used to create deep grooves which will remove a completed or part-complete component
from its parent stock.
Grooving is like parting, except that grooves are cut-off.
cut to a specific depth instead of severing a completed part-complete component from the stock.
Grooving can be performed on internal and external surfaces, as well as on the face of the part,
face-groving or trepening. Non-specific operations include boring, enlarging or smoothing
and existing hole created by drilling, molding, etc., i.e. the machining of internal cylindrical
forms generating, A, by mounting workpiece to the spindle via a chuck or faceplate,
B, by mounting workpiece onto the cross slide and placing cutting tool into the chuck.
This work is suitable for castings that are too awkward to mount in the faceplate.
On long bed laths, large workpieces can be bolted to a fixture on the bed
and a shaft pass between two lugs on the workpiece, and these lugs can.
can be bored out to size.
A limited application,
but one that is available
to the skilled Turner machinist.
Drilling
is used to remove material
from the inside of a workpiece.
This process utilizes
standard drill bits held stationary
in the tail stock
or tool turret of the lathe.
The process can be done
by separately available drilling machines.
Nirling.
The cutting of a serrated
pattern onto the surface of a part to use as a hand grip or as a visual enhancement using
a special purpose knurling tool.
Reaming
The sizing operation that removes a small amount of metal from a hole already drilled.
This is done for making internal holes of very accurate diameters.
For example, a 6mm hole is made by drilling with 5.98 millimeter drill bit and then reamed to
to accurate dimensions.
Threading.
Both standard and non-standard screw threads can be turned on a lathe using an appropriate
cutting tool.
Usually having a 60 or 55 degree nose angle, either externally or within a bore,
tapping operation is a process of making threads either inner or outer in a workpiece,
generally referred to as single point threading.
Tapping of threads, nuts, and holes, A,
using hand tabs and tailstock center,
B, using a tapping device with a slipping clutch
to reduce risk of breakage of the tap.
Threading operations include A, all types
of external and internal thread forms,
using a single point tool also taper threads,
double start threads,
multi-start threads, worms as used in worm wheel reduction boxes.
Let screw with single or multi-start threads.
B, by the use of threading boxes fitted with four form tools, up to two inches diameter threads,
but it is possible to find larger boxes than this.
Polygonal turning, in which non-circular forms are machined without interrupting the rotation of the raw material.
