DIY Project # 9 - Woodworking
Tools for the Do-It-Yourselfer - October, 1998
by Louis Lung
(If you would like to have your DIY project
published in Secrets, please E-Mail Ralph Calabria at firstname.lastname@example.org.)
Table of Contents (Click on the
section you want to see)
About the author - by Ralph Calabria
When I asked Lou to write this article,
I was well aware of his knowledge of woodworking skills, both
in furniture making and speaker building. Lou has been a woodworker
for some time now, and the fine craftsmanship seen in his work
is testimony. Lou's many speaker-building projects include:
a 3-way tower design using an ACI AC-10 woofer, Focal 5N313 mid,
and Scan Speak D2905/9000 tweeter; a design of the NHT 1259 that
looks more like a decorative pedestal than a subwoofer; and a
budget 2-way using a Vifa 5" mid and a SEAS 1" tweeter.
His furniture-building credentials include a bunk bed made from
cherry, an armoire, and a mahogany nightstand.
Speaker building is not just an exercise
in audio engineering; it is also a construction project. For the
beginner, obtaining the proper woodworking tools can therefore
be as daunting a task as driver selection. This article will attempt
to shed some light on basic woodworking tools. Each tool will
be viewed primarily from a speaker building perspective, although
any do-it-yourself project may be substituted. I will try to look
- Features and Functions - variations, features,
and functions typically available.
- Speaker Building Uses - how useful is
this tool in our pursuit?
- Add-Ons - related accessories that make
this tool work even better.
- Usage Tips - making the most of this tool
for our projects.
- Cost - always a factor!
Of course woodworking tools are not limited
to speaker building. These same tools can be used to build speaker
stands, stereo cabinets, room treatments and traps, even complete
sound rooms. For simplicity, however, the term "speaker building"
will be used throughout this article to denote all of the above
This article will not attempt to cover all
aspects of tool usage or woodworking in general; nor will it address
tools and techniques necessary for building exotic shapes and
compositions. It is an article geared toward the beginner, and
basic rectangular boxes are the assumed goals.
Since I'll be merely scratching the surface
on tool usage, it's essential that readers take the time to read
and understand each tool's user's manual. Taking the time to understanding
the fundamentals of each tool, how it works, what its limitations
are, and most important of all, how to use the tool safely, is
the first step to building a successful project.
There is no way for me to cover all details
of each tool. Manufacturers are constantly upgrading their wares
with better features and innovations. My goal is, therefore, to
cover most of the important points that I consider relevant to
speaker building. As always, there will be exceptions to every
rule, so keep that in mind.
Tool prices provided are approximate and
reflect the market as of this writing. Prices are intended to
give readers a feel for the relative and absolute costs of the
tools. Some brands and models may cost significantly more or less
than others. All prices are in US Dollars and do not include any
taxes, shipping or handling charges.
I've tried to avoid using brand names except
in the URL section. The intent is to concentrate on the characteristics
of the tool, not the actual commercial offerings. Woodworking
magazines regularly review tools and are the best source for up-to-date
Note on Safety and Maintenance
All tools are potentially dangerous. They
should be treated with a healthy dose of respect and care. Always
read and understand the manufacturer's directions on both safety
and usage before using a tool. Always use appropriate safety equipment
including eye (safety glasses), respiratory (mask), and hearing
protection (earplugs). Always maintain the proper work environment,
and give your tool and work your undivided attention. Remember
- safety first !
Proper care and maintenance is required
on all tools. Refer to the manufacturer's directions for such
information. Keeping tools in tip-top shape not only maintains
tool life and maximizes performance, it also helps prevent accidents
and potentially dangerous operating conditions.
This section is a very simple look at power
tool motors. I won't go into great details - just enough to guide
you through some of the numbers you'll likely see when shopping
for power tools.
There are two basic types of power tool
motors: induction motors and universal motors. The induction
motor is typically found on large tools and can deliver fairly
consistent and reliable power. It is characterized by its single
speed and large cylindrical case. Induction motors are usually
used on drill presses, table saws,
jointers, and other floor standing machinery.
Changing speed, when allowed, usually means moving belts between
pulleys of varying sizes. By comparison, the universal motor is
small and loud. Its size and weight makes it ideal for handheld
tools like portable drills and routers. With no load, the universal
motor usually spins at a rather high rate. Under load this rate
drops dramatically, and the motor heats up quickly.
Both types of motors are rated in horsepower,
but the actual numbers can be deceiving. For example, a typical
115 VAC induction motor in a contractor table saw drawing 14 amps
may be rated at 1.5 Hp. The same 14 amp in a router with a universal
motor might be rated at 3 Hp. Suffice it say that universal and
induction motors should not be compared with each other. When
comparisons of any sort must be made, make them when they are
of the same type, and use the motor's current draw for comparison,
not the horsepower rating. Avoid making judgements based on small
differences in current or horsepower draw. Large differences in
horsepower or current rating are more likely to be accurate on
a relative basis. For example, a 3 Hp router is likely to be more
powerful than a 1.5 Hp router, though not necessarily twice as
Induction motors come in various flavors.
The best are Totally Enclosed Fan Cooled (TEFC) motors. Most large
power tools from respectable companies come with such motors.
Less expensive tools often come with Drip-Proof motors. These
offer less protection from the environment than TEFC motors. In
some applications, explosion-proof motors are required. Typical
uses include exhaust fans used in handling combustible gases.
What differentiates a consumer grade tool
from a professional grade tool aside from price? Are these differences
worth the extra cost? Let's take the easy question first and identify
some differences between consumer and professional tools. Typically,
- Are designed for long life under tougher
environmental conditions. This may include motors capable of
withstanding higher temperatures, use of better dust seals, bearings
and lubricants, and stronger, more durable construction.
- Deliver better overall performance, including
motors that provide smoother power with less vibration.
- Tend to have more accessories, options
- May use more advanced and expensive materials
such as light-weight alloys or use of cast instead of stamped
- Are designed with serviceability in mind.
Should the hobbyist invest in costlier tools? This is a personal
question, and the answer will vary with each individual. Variables
to consider include the predicted amount of actual tool usage,
the care one puts into proper maintenance, the desired accuracy
from each tool, the desired work efficiency, and of course cash
flow, to name but a few. Consider such variables before spending
any money. In many instances, a pro-sumer or consumer level tool
is all that's needed. In other instances, professional tools are
a worthwhile investment.
Note: In the various tools discussed
below, my comments assume a "decent" level of tool quality.
Poor quality tools usually lead to poor results no matter how
hard one tries. This does not imply top-notch tools, but rather,
just good enough, relative to the user's expectation. This is
obviously a tricky statement to make, and impossible to quantify
in a general sense.
It's easy to understand why so many consider
the table saw to be the indispensable saw in the
shop. With a table saw, one can make an abundant number of cuts,
most with a high degree of precision. Jigs and accessories can
make the table saw invaluable.
Features and Functions
I group table saws into three categories:
the bench saw, the contractor saw, and the cabinet saw. The
cabinet saw is the largest and most accurate. It usually comes
with a full-size polished cast iron top, a totally enclosed base,
a large and accurate fence, a large 230 or 460 VAC single or three
phase TEFC motor, a 10 to 12 inch blade capacity, and plenty of
working surface. It is used primarily by professionals, and by
hobbyist standards, is quite costly.
On the other extreme is the bench table
saw. This is usually a small device designed to be clamped onto
a benchtop or mounted onto an optional floor stand. It operates
off a regular outlet (~115 VAC in North America) and consequently
is limited in motor size. The blade is usually 8 to 10 inches
in diameter, and the fence may need some tweaking to get that
great cut. Bench saws are great for the hobbyist with limited
space or needs. Because of their portability, bench saws are also
a great professional job-site saw.
Between the cabinet saw and the bench saw
is the contractor's saw. Like the bench saw, these saws usually
operate from regular household outlets. They also offer some of
the added size, weight, and stability of the cabinet saw. The
contractor's saw typically has a cast iron surface with an open
frame. The typical blade size is 10 inches. Fence quality varies,
though after-market fences are usually available as upgrades.
There are many qualities that makes one
saw better than another. Here are a few in no implied order:
- Cast iron top - a well-made saw is ground
and polished flat. It will take lots of abuse, and with proper
care, will last a lifetime. Stamped steel or aluminum, while
lighter, do not provide the mass needed for stability and accuracy.
- A straight, easily adjustable fence -
the job of the fence is to keep a parallel surface with respect
to the blade. Some believe that the fence should be slightly
off parallel - the rear being further from the blade than the
front, thus ensuring that the rear will not touch what's already
been cut. No matter what you believe, it's important never to
let the rear
of the fence be closer to the blade
than the front. Some fences have micro-adjustments
that make small incremental fence changes easier to make.
Some fences lock only on the front rail, while others lock on
both the front and rear rail. Most of the quality fences lock
only in the front.
- TEFC motor - for 115 VAC, the most you'll
get is about a 1.5 Hp induction motor. Anything larger is usually
wired for 230 VAC operation. Universal motors are not common
in table saws and are not a good choice.
Speaker Building Uses
Table saw uses should be fairly obvious.
Some typical uses are:
- Cutting large sheet goods down to size.
- Cutting dadoes and grooves. This is usually
done for nice, strong, clean, tight fitting joints.
- Cutting miters for corners and other "odd"
angled panels. One or more jig or accessory may be needed to
perform these tasks accurately.
Here are some useful accessories:
- One potentially very useful and important
safety accessory (when not standard equipment) is a magnetic
switch. A magnetic switch consists of a pushbutton on/off switch
that engages power via a relay. It operates like a regular switch
except when power is interrupted. Should a partial or full power
failure occur, the relay opens and power is cut to the motor.
When power comes back on, be it a split second or hours later,
the relay does not re-engage until it is turned on again. This
prevents sudden restarts caused by brown-outs, thus preventing
- A better after-market fence can dramatically
improve the performance and accuracy of a saw. Not all saws can
accept after-market fences, so check availability before buying.
- Dust collection does wonders to air quality
in a shop. A table saw is capable of throwing an enormous amount
of dust into the air. Dust collection removes most of the small
and troublesome particles. Some saws come with built-in collection
hookups, while others require some user hack.
- Hold-downs are a great safety and precision
addition to a saw. Most hold-downs clamp onto the fence and provide
downward pressure to the tabletop and sideways pressure to the
fence. Should kickback occur, the hold-downs limit the amount
of travel on the stock, preventing it from going airborne.
- Stand-mounted rollers placed on the side
and rear of a table saw can effectively extend its capacity when
cutting large sheet goods. These rollers are not expensive and
normally have many other uses around the shop.
- A panel cutter is a jig that rides in
the saw's T-slot, which provides right-angle cuts for large sheet.
This jig differs from the standard T-slot miter gauge mainly
in size and purpose. While the miter gauge allows you to set
any cut angle, the panel cutter is usually made just for right
angles. Most woodworkers make their own panel cutters.
- A tapering jig forms a wedge between the
stock and the fence resulting in an angled cut. This jig is useful
for making panels with non-parallel sides. A speaker with a sloped
baffle might require such a panel on each side of the cabinet.
- Zero clearance insert - The insert is
a plate through which the blade rises on the table. A zero clearance
insert starts out as a solid piece of material through which
the blade is slowly raised. The result is an insert that has
a minimum amount of clearance all around the blade, thus maximizing
support for the wood as it is cut. This is easily made in the
shop from scrap hardwood.
Many of the items listed below are usually
mentioned in the user's manual:
- Use the anti-kickback device supplied
with your saw whenever possible.
- Use the splitter supplied with your saw
whenever possible. Splitters are usually temporarily removed
or displaced when cutting dadoes or grooves. Be sure to reattach
them after completing the cut.
- Use a zero clearance insert when working
with small items that may require extra support near the blade.
- Always wear eye and ear protection.
- Never stand in line with the blade.
- Never force stock through the blade; let
the blade do the cutting.
- Wear a full face shield (in addition to
eye protection) when cutting particle board or similar material.
Flying chips can strike the exposed skin on your face.
- Use dust collection when cutting medium
density fiberboard (MDF). MDF releases a lot of very fine dust
when cut. A respirator can keep this dust out of your lungs,
but won't keep the dust from coating your shop surfaces.
- The blade should rotate down into the
stock meaning that any tearout occurs on the underside. It is,
therefore, good practice to put the good side of the stock up.
If tearing on the bottom is a problem, try adding another layer
of scrap stock on the underside and cut through both layers.
Masking tape along the cut line can also be used so long as it
does not damage the stock when it is removed.
- Bench saws: usually under $200
- Contractor's saw: $500 to $1,000
- Cabinet saw: $1,000 and up
The router is a portable, multi-purpose
power tool. Functionally, it's a very simple device, but with
the proper jigs and/or attachments, a router can perform a variety
of tasks. For example, routers can cut dadoes, mill moldings,
cut biscuit slots, create dovetails, drill holes, join edges,
and even plane surfaces flat.
Features and Functions
There are fundamentally three types of routers
- fixed base, plunge base, and D-handle:
routers are the most basic. They usually have a pair of handles
near the base of the unit. The extension of the bit (the depth
of cut) is set before use. Depending on the make and model, the
fixed base router may be easier to use when mounted in a router
routers are similar to fixed-base routers except that the router
is controlled mainly via a D-shaped handle. These are probably
the least common of the three types.
routers are the most popular and allow the bit to plunge into
the wood, hence their name. The plunge depth is adjustable, often
in very small increments. This is clearly the most useful of
the three types, but also the most expensive. Most high power
routers are plunge models, and not all plunge routers are suitable
for table mounting.
Routers fall into two groups based on their
power. Low power units range from just under 1 Hp to about 2 Hp.
High power routers range from 2.5 Hp to about 3.5 Hp. From a current
draw basis, all routers typically draw from 10 to 15 amps. High
power routers tend to be bigger and heavier. From a capability
standpoint, the rated power of a router does not, by itself, define
what it can do, or how quickly it can do the job. However, advanced
features, options, and accessories are more likely to be available
on larger, pricier, and more powerful models.
Some features that differentiate routers
from one another include:
- Soft start - reduces the kick produced
when the router starts up. In applications where the bit must
make contact with the stock when the router is turned on, this
feature helps reduce the likelihood of gouging the stock.
- Variable speed - a typical router can
spin a bit (with no load) upwards of 20,000 rpm. This can be
very dangerous with larger diameter bits since the wider the
bit, the faster the perimeter of the tips travel at a given rpm.
Variable speed is a "must-have" when using large diameter
bits. Slowing the bit speed also reduces friction and thus reduces
the likelihood of burning the stock from friction.
- Collet size - router bits come in 1/4
and 1/2 inch diameter shanks. The larger shank offers more stability
and is therefore used with larger bits. Smaller bits are offered
either in 1/4 inch shank only or in both sizes. Some routers
only have a 1/4 inch collet, thereby limiting bit selection while
others provide both 1/4 inch and 1/2 inch collets.
- Micro-adjustment - Some routers make fine
depth adjustments very simple and accurate. The micro-adjustment
feature is very handy when attempting to get precise cut depths.
Speaker Building Uses
There are many important uses for a router.
Some typical ones are:
- Cutting circular holes for drivers in
- Milling cabinet edges. This is usually
a roundover or chamfer.
- Cutting grooves and dadoes inside cabinets
to accept shelf bracing.
- Cutting rabbets to cabinet side panels
for panel joinery.
Because the router is so versatile, there
are many accessories available. Many can be made in the shop.
- A circle-cutting jig is a popular homemade
jig due to its simplicity. The concept is straightforward, and
can be made in a variety of ways. One example is to use a board
that has a router mounted on one end, and pegs placed some distance
away from the router's bit. The assembly's peg is inserted into
a hole in the stock to be routed and acts as the center of a
the circle. By varying the distance between the router and the
peg, the radius of the circle that the router will mill is changed.
Commercial circle cutters may be mounted to the router in place
of the base plate or may be mounted to some other point on the
router's lower section. Radius adjustments should be easy to
make, and may contain a fine-adjustment feature for precise settings.
This is a "must-have" accessory for speaker building.
- An edge guide is useful when milling dadoes
and grooves that are parallel to one edge of a panel. The guide
follows the edge of the panel, maintaining a parallel and repeatable
cut. Some edges can also ride in an existing groove, thus allowing
one dado or groove to be cut parallel to another. Never try to
cut a dado or groove freehand. Always use a guide or follow a
- For some users, a router table provides
a more secure and stable platform for routing. A router table
holds a router upside-down with the router mounted from the underside.
The bit sticks out of an opening through the table. The depth
of cut is preset before milling. It's not practical, or safe
to plunge up from below while the stock is sitting above the
bit. The stock is moved over the router in full view of the bit.
The benefit of the router table is in the added stability provided
by the table, more precise control, better visibility of the
bit, and increased contact area between the stock and router.
Many router tables have fences, dust collection attachments,
and clear polycarbonate plastic shields that cover as much of
the bit as possible for safety. More advanced tables provide
features found in large shapers such as a T-slot. Router tables
can be stand-alone or built as part of a table saw surface. Many
of the parts needed for a home-made router table are readily
available at woodworking stores.
Here are some tips for using a router:
Never try to remove too much material at
once. It's better to use multiple passes, each removing a little
more material. How much is too much? This is partly a matter of
experience and partly a matter of common sense. If the stock offers
a lot of resistance, or if your bit clogs up with sawdust forcing
you to stop, you may be trying to remove too much stock at once.
Also, check the grain of the stock and see if it's likely to tear
with the bit rotation. You can minimize tearout by removing less
stock per pass. As a rule, I like to make at least two passes
on each cut, with the last one removing a minimal amount of material
to clean up any aberrations left over from previous cuts.
Whenever possible, move the router in the
direction such that the bit's rotation is against the direction
of motion. This forces the bit into the wood instead of allowing
the bit to pull the router along. The user's manual should diagram
this since it's one of the most important points to remember when
using a router. Make sure you understand this.
For our uses, this translates to the following:
- If you're milling the inside edge of a
driver hole (e.g., milling a recess for the driver flange with
a rabetting bit), move the router in a clockwise direction inside
- If you're milling the exterior of the
box (e.g., milling a roundover on the baffle edges), go counterclockwise.
- When milling end grain, it's easy to tear
the wood at the edges. One simple way to avoid this is to clamp
scrap wood of the correct size to the end of the stock and mill
it with the stock. This causes any tearing to show up on the
scrap, not your stock.
- When using a router to mill a round driver's
opening in a baffle, do all your baffles together. Setup is crucial,
so take your time, set it up right, and then do all baffles the
- If you have spare stock, mill one or more
extra baffles. These need not be full size - just large enough
to hold the driver's opening. The purpose of these spare baffles
is to let you test your setup when you have multiple routing
steps. Use the spares when proceeding from one step to the next
to test your setups without risking your real baffles.
- If you're flush-mounting the driver, be
sure to allow some extra depth for the mounting gasket.
- When cutting the hole for the driver's
basket, make sure not to cut through without taking some precautions.
The circle cutting attachment is mounted to the center of the
driver's opening and will be loose when it's cut free of the
- Two ways to solve this problem are:
- Mount some scrap on the underside of the
baffle temporarily to secure the center waste to the rest of
the baffle. Remove it after you've routed the circle and separated
the center waste from the baffle.
- Don't mill all the way through the baffle,
leaving about 1/16 inch holding the center in place. When you're
done routing, cut through the remainder with a jig saw or hand
saw (a keyhole saw works well). The cut may not be perfect, but
since it's on the inside of the baffle, it's not visible and
won't affect performance.
- If you wish to bevel the inside of a driver
opening, use a pattern-following bit. This bit has a bearing
that rides along the inside rim, and removes stock evenly around
- When possible, get 1/2 inch bits instead
of 1/4 inch bits. They do tend to cost more than 1/4 inch bits
(all else being equal) but are more stable.
- Carbide bits are a worthwhile investment.
Wood products such as Medium Density Fiberboard and particle
board eat High Speed Steel (HSS) bits. There are many advanced
bit designs including anti-kickback features, low friction Teflon
® coating, and modular construction. Invest in these bits
if your budget allows.
- Professional high performance, high power
plunge router: $200 to $300
- Professional fixed base low power router:
$100 to $200
- Consumer router: under $100
Portable Circular Saw
The circular saw is probably one of the
two most basic and common power tools around (the other being
the drill). It is the ultimate fast cutting tool - portable, capable,
flexible and affordable. It can be used in the shop or on a job
site, and may be used for rough as well as highly accurate cuts.
Features and Functions
Circular saws tend to look more or less
the same. Yet there are differences in their designs.
- The majority of circular saws on the market today
have side-mounted motors. These are the familiar saws with the
blade directly in-line with the motor shaft and housing. Power
is typically delivered from the motor to the blade via reduction
gears. Less common are worm-drive saws often used by professionals
needing higher torque and a narrower saw profile. The motor is
mounted behind the saw blade, parallel to the direction of cut,
and connected via worm gears.
- The grip on a saw is either on top or
behind the motor. Professionals often prefer the latter design
since it gives them more reach. Either design offers a second
grip or knob on the front of the saw for two-handed operation.
- Many saws come in both right and left-handed
- The depth of cut is controlled either
via a drop foot or a pivot foot. The pivot foot is easier to
use, but changes the angle of the handle relative to the stock.
- Some advanced saws have an electronic
brake to quickly stop the blade when power is cut. This can be
a valuable safety feature as well as a time saver when making
many consecutive cuts.
- For keeping dust in check, some saws have
adjustable dust ports that can be aimed away from the work or
even attached to some sort of dust collection system.
Speaker Building Uses
For serious DIYers, the circular saw can
be seen as a poor man's table saw. But like its bigger and more
expensive brother, this saw can make excellent cuts with the right
jigs. Even dadoes are possible, though they require much more
care in setting up the cuts. Cutting small stock is difficult
with this saw, so use a hand saw for safety.
I tend to think of the circular saw as a
straight cutting tool without a fence. The flat blade of this
saw dictates a straight cutting path, yet the saw is really free
to go anywhere, thereby risking binding and kickback. So, the
most important accessory to this saw is a straight edge. A straight
edge can be anything from a pre-made commercial unit with built-in
clamps, to a piece of plywood with a factory edge. The important
thing is that the saw has a surface to ride against, thus keeping
it in a straight path.
One notable difference between a table saw
and a circular saw is the direction of the blade's rotation. As
mentioned earlier, the table saw blade rotates down into the stock.
The blade on a hand-held circular saw rotates up from the bottom
and through the stock. This means that tearout occurs on the top
side of the stock. You should, therefore, cut your stock with
the good side down. To avoid tearout on the top side, use masking
tape along the cut line (assuming the material will not be damaged
by tape). Adding a second layer of scrap stock on the top side
may be done if the layers are properly supported and secured.
To cut a straight line, use the aforementioned
straight edge. Clamp the straight edge down as solidly as possible.
Some saws have accessories that make ripping parallel sides easy.
Check the manufacturer's catalog for these accessories.
- Professional heavy duty, high performance
saw : $150 to $200
- Professional saw : $100 to $150
- Consumer saw : under $100
Functionally, the jig saw is very similar
to the circular saw except that it cuts much more slowly and can
cut curves. This saw is sometimes referred to as a sabre saw.
Jig saws are very portable, relatively quiet compared to their
larger circular bladed cousins (important to apartment dwellers
!), and safer in many respects. What they lack in cutting speed,
they make up in flexibility.
Features and Functions
are several types of blades, not all of which are supported by
all vendors. The universal blade is the most common. It has a
straight shaft with a hole at the mounting end. The hook mount
is supported by Porter Cable, and as its name implies, has a
90 degree hook for mounting. The 'T' or tang or bayonet mount
has a mounting system shaped like a small sword. Each blade type
does the job well. The main differences are in the ease of changing
blades. Whether such ease is worth the distinction of one make
and model over another is a personal matter. If you change your
blade often, a one-step, toolless changing system can be a time
saver. But if you're a rare user of a jig saw, it's probably
not worth much as a unique differentiating feature. What is important
is that any tool needed to change a blade (if any) be readily
- Simple and inexpensive jig saws have a
single reciprocating stroke. More advanced saws offer two strokes
- reciprocating and orbital. The reciprocating motion is a simple
down and up stroke. This offers the smoothest but slowest cut.
Orbital motion causes the blade to push down in a straight motion,
but pull back up with the blade angled forward. Since jig-saw
blades cut on the upstroke, this has the effect of cutting more
aggressively. Saws that offer orbital motion usually allow more
than one orbital setting. This setting varies the aggressiveness
of the up-stroke.
- Simple jig saws have only an on/off switch.
Costlier models allow control of the stroke speed either by the
amount of trigger pressure (as in a drill), by a dial setting,
or both. If a dial setting is used, it should be mounted in an
easy-to-reach place so that speed adjustments can be made during
the cut. Some models allow a number of fixed speeds, but offer
no continuously variable settings.
- Jig saws remove waste slowly and do not
tend to throw large amounts of dust. However, since they cut
on the up stroke, dust usually accumulates on the cut line. Some
saws have small blowers that push this dust aside while you cut.
Others provide dust collection hookup.
- Almost all jig saws offer a base that
tilt up to 45 to the left and right. Usually a 90 stop is provided,
as well as possibly other common angles. At least one manufacturer
provides a rigid non-tilting base. Fixed-base jig saws offer
a more stable platform and remove the possibility of accidental
- Most jig saws have a top-mounted D-shaped
handle. This handle may be placed almost on top of the blade
assembly or it may be placed further back on the body. Another
grip style is the body grip, where the unit's body is used to
hold the saw. This grip places the hand closer to the work surface,
usually offering more accurate control of the saw.
- Blades - Some are made for specific uses
such as wood or metal cutting. Blade materials and teeth specifications
also vary with application and cost. If the jig saw is your primary
tool, invest in quality blades. If this is an occasional tool
more likely to be used for rough work, you can be less selective
with your blades.
Speaker Building Uses
There are several ways to think of the jig
saw. For someone on a limited budget, it can be the one and only
power tool. With care, it can cut holes, curves, straight lines,
and even bevels. Its accuracy is almost entirely a function of
the user; and any resulting ragged edges can often be sanded down.
Where one's budget is not an issue, the
jig saw is more useful supplementing other power tools. Its ability
to cut curves and bevels make it ideal for roughing out holes
for surface-mounted drivers, especially those requiring odd shapes.
Jig saw accessories are few, and tend to
be very manufacturer specific. Below are some possible accessories.
If any of these are important to you, be sure to check with the
manufacturer or dealer before you buy:
- Dust collection hookups (when not standard
- Edge guide to cut lines equidistant from
an existing edge
- Circle cutting guide similar to that used
on a router but made specifically for a particular jig saw
- Rail cutting system where the saw rides
on a clamped rail to cut straight lines
- Anti-splintering device that keeps the
stock down just in front of the blade
- Blade support and deflection - A jig saw
blade is mounted only at the top and may be influenced in its
path by the stock. Saws provide varying levels of blade support
either from the rear of the blade, from the side or both. The
goal is to keep the blade as straight and stable as possible.
Cutting tight curves, especially on thick stock, will always
place strain on the blade. The greatest strain and deflection
will occur at the tip (bottom) of the blade furthest from the
saw body, and will tend to cause the blade to bend towards the
inside of the curve. Be aware of this and cut slowly to minimize
- Starting a hole - One of the jig saw's
greatest assets is its ability to cut inside an enclosed region
such as cutting a rough opening for a driver in a baffle. There
are two basic ways to start the cut. The simplest is to drill
a hole large enough to insert the blade of the jig saw. If a
hole cannot be drilled, the jig saw can be used to cut a slit
into the stock. This is done by leaning the saw forwards at a
steep angle such that the tip of the blade is barely making
contact with the stock. With the motor running, slowly tip the
saw back towards its normal position, thus pushing the blade
down into the stock. Do this slowly. The drawback of this technique
is that it will not work in tight spaces.
- Cutting straight line - A jig saw can
be used to cut a straight line with the use of a straight edge
guide. A dedicated guide made specifically for the jig saw is
best but any straight edge clamped to the stock may be used.
Straight cuts are a good use of orbital strokes.
- Cutting curves - The sharper the curve,
the less likely an orbital stroke will prove suitable. When in
doubt, use a reciprocating stroke t.
- · To help limit splintering - Use
masking tape and draw your cut line directly on the tape. This
is no panacea, but should help. Test first to make sure the glue
from the tape will no stain the stock you're using.
- Professional high performance jig saw:
$100 to $175
- Consumer jig saw: under $100
The other highly popular home power tool,
the drill, is an incredibly simple tool that should require little
explanation to anyone interested in DIY.
Features and Functions
or corded - While the cordless drill has replaced the corded
drill in many applications, a corded drill is still a valuable
tool in any shop. Corded drills still offer much more power and
torque than their battery-powered counterparts. They also tend
to be cheaper and you never have to worry about dead batteries...
just power failures! For the hobbyist on a limited budget, a
basic corded drill is a good investment whose only drawback is
its umbilical to the wall. The more advanced hobbyist with lots
of uses around the shop and home will probably find the cordless
drill more useful. Ultimately, your possible uses will dictate
what to buy. Heavy vs. medium vs. light duty, features, and portability
are probably the key considerations, though by no means the only
- Keyed or keyless - Traditional drills
require a key to tighten a bit or shaft in the chuck. Keyless
chucks only require hand tightening. For the most part, keyless
chucks have become standard equipment on most cordless and many
corded drills. From my experience, a quality keyed chuck will
always hold tighter than a keyless chuck. In some applications,
this may be important. For the audio hobbyist, this is not likely
to be an issue except in some extreme cases.
- Built-in clutch - A drill with a built-in
clutch becomes a very useful screwdriver. Clutches are usually
adjustable over a wide range of torque settings, typically by
turning a ring near the chuck. The clutch allows the drill shaft
to rotate only when pressure is applied and only up to the chosen
torque setting before disengaging. This is very useful for driving
applications - clutches can prevent the overtightening of screws
or the stripping of screw heads.
- Variable speed and reversible - Variable
speed reversible (VSR) is standard today. It may not be possible
to settle for less! The reverse direction can be used for extracting
screws or for removing stubborn drill bits from their hole. The
reversing switch should be easily reached by the hand on the
- Voltage and torque - Cordless drills are
usually listed by their operating voltage. Voltages are usually
multiples of 1.2 V - the voltage of a single Nickel-Cadmium cell.
Most of the units less than 12 volts are better suited for general
home use. For serious hobby use, go with 12 V or higher. Torque
is sometimes advertised along with voltage. Most cordless drills
have a two speed range that trade speed for torque. Typically,
torque is not that big a factor when comparing drills of similar
- Handle location - There are two types
of handle arrangements for drills - pistol grip and T grip. Each
has its proponents and detractors. The T grip provides better
balance while holding the drill. Users who are physically weaker
will likely find this shape more comfortable especially when
drilling in an awkward positions. In my opinion, the pistol grip
provides better directional force and control when drilling and
driving. The uneven weight distribution is countered by the support
provided by the drill bit biting into the stock, while the angle
of the pistol grip allows more force to be exerted. If you are
unsure when buying, try both styles, but remember to try them
with real bits and real wood. Simply holding it for balance doesn't
mean much since it's the act of drilling that actually is important.
Try different drilling positions if possible, such as holding
it sideways or overhead.
- Kits - Cordless drills are often available
in kit form. This is largely due to the need for a second battery
while the first charges. Kits usually contain two batteries,
a charger, drill and case. If you must buy a cordless drill,
a kit is usually worth the investment if cost is not an issue.
If funds are tight, most drills are also sold with a single battery
- Brakes - Some drills stop on a dime via
an electric brake. This can be a very useful feature when doing
many consecutive operations. For normal use, it's a nice feature
but not a necessity.
Speaker Building Uses
The obvious use in speaker building is drilling
holes (pre-drilling is a good idea to avoid splitting stock),
and driving screws. Do not use portable drills with bits intended
for the drill press. For example, it's possible to mill very accurate
circles with an adjustable one-armed T-shaped circle cutter. However,
this is strictly a drill press tool and using it on a hand held
drill is very dangerous.
- 1/4 inch hex extenders - Most driver and
socket bits are very short. An extender chucks into the drill
while its female end magnetically holds the bit firmly in place.
- Drill/driver units - There are several
jigs on the market that allow the user to switch from drilling
to driving very quickly. They vary in design, price and usability.
Each typically allows the user to drill a hole with a countersink,
then switch to the driver without having to touch the chuck.
- T-square - The visually challenged may
want a small T-square or other right angle tool to guide the
- If available, choose the correct speed
setting. The slower setting gives more torque.
- Excessively high drill speeds can burn
wood and dull bits unnecessarily.
- · Reversing the bit direction makes
bit extraction easier.
- Countersink screws to hide the screw heads.
- Start with a low setting when you're unsure
of the torque needed to drive a screw into a particular stock.
- Professional high performance, high voltage
cordless drill kit : $200 to $250
- Professional high quality cordless drill
kit : $150 to $200
- Professional high performance corded drill
: under $100
- Consumer corded drill : under $50
I've decided to place saw blades in its
own category in order to highlight the possible choices. The simplest
shop can get by with a single all-purpose combination blade. On
the other extreme, the professional shop might have many highly
specialized bladed in addition to the general purpose ones. For
the speaker builder, it's possible to get by with one blade, but
having one or two special blades can be very handy.
Blades come in various sizes. The two most
common sizes are 10 inches for table saws, and 7-1/4 inches for
hand held circular saws. Both are typically made for a 5/8 inch
arbor thus the smaller 7-1/4 inch blade can be used in a 10 inch
table saw though the reverse does not apply.
Features and Functions
- Stack dado head blades - One very important
accessory for a table or radial arm saw is the dado blade. Whereas
a typical circular saw blade cuts a path as wide as its teeth
allow (the kerf), a dado blade cuts a wide path through the stock.
The stack dado head cutter usually consists of two full size
blades sandwiching a number of chipper blades. The chippers are
usually not full blades and their job is to remove the stock
between the two edge blades. By varying the number of chipper
blades and their widths, the width of the cut is changed. The
typical stack dado head set is 6 to 8 inches in diameter.
- Wobble dado blades - The wobble dado blade
performs the same function as the stack dado blade but has two
very important differences:
- 1. The wobble dado is a single unit, not
a number of blades that are stacked to perform the task. Wobble
blades usually have one or two blades that are tilted to carve
out the full width of the cut. The side affect of this action
is that the bottoms of the dadoes cut are not flat; but are curved.
Furthermore, the lack of full contact side blades means the edges
of the dado are not often as crisp as that made by a stack dado
- 2. The width is continuously adjustable.
It is not limited by the width of the chipper blades. Thus, fine
tuning the width is much simpler with a wobble dado than with
a stack dado blade.
- Thin kerf blades - Thinner blades remove
less material as they cut, and therefore require less power to
use and produce less dust. They are also not as stiff as their
regular kerf counterparts, so they must be more carefully designed
to avoid warping with heat buildup. Blades often have expansion
slits to avoid such warping.
- Ripping blades - Blades made specifically
for ripping tend to have fewer teeth (24 is typical on a 10 inch
blade). This allows more room between the teeth for waste removal
leading to a faster cut.
- Crosscut blades - In order to avoid tearing
the wood fibers during a crosscut operation, these blades tend
to have many teeth (60 to 80 is not unusual for a 10 inch blade).
The high number of teeth means there's less space between teeth
for material removal. These blades cut more slowly but more cleanly.
- Combination blades - To strike a balance
between ripping and crosscutting, a combination blade typically
sports 40 to 50 teeth. As expected, it is slower than a ripping
blade while ripping, and rougher on crosscuts than a crosscutting
blade. If your budget only allows for a single high quality blade,
a carbide tipped combination blade would be a good investment.
- Other specialty blades - The blades I've
mentioned above are the more common ones. For special applications,
there are blades for cutting all types of materials including
Corian ® , plexiglass, non-ferrous metals, plastics, laminates,
decking, plywood, etc.
- Carbide - Standard blades are made from
steel. These will dull very quickly especially when cutting composite
materials such as particle board or medium density fiberboard.
Carbide blades are a worthwhile, if not a necessary investment.
Speaker Building Uses
The better the blade, the better the cut.
Dado blades are very useful for milling rabbets or grooves. A
shelf brace inside a speaker or stand could easily be made to
fit snugly by milling a dado on all side panels in which the shelf
Blade stabilizers - The typical table saw
clamps the blade on either side of the blade, near the center
spindle. A blade stabilizer consists of two round metal plates
that clamp the blade further away from the center of the blade
thus reducing blade chatter. There are three major side affects
to be aware of when using such a stabilizer:
1. The stabilizer moves the blade away
from its regular position relative to the fence. This means all
distance markings are now wrong.
2. The slot in the table saw insert may
no longer match the blade position. A custom insert can be made
from some hardwood much the same way a zero clearance insert
3. The maximum blade height is reduced.
Dado blade shims - Shims may be plastic
or metal, and come in various thicknesses. They are inserted between
dado head chippers to fine tune the cutting width.
- Follow regular maintenance on your blades
as you should with all your tools. Remove any burned-on residue
and never use a dull or broken blade.
- Because dado blades remove much more material
than conventional blades, feed your stock more slowly. As with
a router, make multiple passes, removing a little more each time
rather than trying to remove too much material at once.
- Professional high performance specialty
blade : can be over $100
- · Professional high performance
10 inch blades : $40 to $60
- Typical 10 inch blades : under $40
- High quality 8 inch stack dado blades
: under $150
Before we continue through other essential
tools, let's take a brief side trip to visit other saws. Depending
on your interest, skill, and resources, some of these saws might
serve you very well in many uses. Needless to say, this list could
easily get as large as the rest of this article, so I am only
listing a few select items:
- Radial arm saw - The radial arm saw is a very useful and flexible
saw. It excels at crosscutting stock at various angles. It can
also be used to rip stock by rotating the head 90 degrees. For
an only saw in a speaker builder's shop, this is not the tool
- Chop or miter saw - I am actually referring to several types of
saws here. The simplest miter saw provide a simple chop action
and is usually capable of providing a miter in the range of +/-
45 degrees to the left and right by rotating the saw head relative
to the saw fence. The more sophisticated compound miter saw allows
the head to tilt, thus cutting two angles at once. For larger
cutting capacity, the sliding compound miter saw has a rail system
on which the saw head rides. This allows the head to extend forward,
increasing the cutting capacity that would otherwise be limited
by the blade diameter. This latter miter performs many of the
functions of the radial arm saw and can be quite costly.
- Band Saw
- Some woodworkers consider this
saw to be the most useful of all saws. The band saw can rip,
crosscut, and re-saw. It can cut straight lines as well as curves.
Best of all, it is very safe since kickback is non-existent.
One thing it cannot do is mill dadoes. For the speaker builder,
this is not the first saw to get, but for the woodworking junkie,
it is a highly desirable and indispensable tool.
- Hack Saw
- The interchangeable blade make
this the perfect low cost tool for cutting all kinds of materials.
While this article is about woodworking
tools for the DIYer, the soldering iron is a necessary tool when
considering soldering your own crossovers and performing mods
to your existing equipment.
Features and Functions
- Grip style - soldering irons are either
pencil shaped or pistol shaped. For control, I personally prefer
the pencil shape, but this is obviously a matter of personal
taste and preference.
- Power (watts) - hobby soldering irons
are sold for many purposes. They range from low power devices
such as those for electronics to high power units for use with
stained glass. It's important to use an iron of the correct wattage
to avoid excessive or insufficient heat. For speaker building,
a small iron suitable for soldering crossovers and other electronic
parts would be in the 30-watt range. Some irons have selectable
temperature settings, which, while not necessary, might be of
use to the more experienced user.
- Tips - Irons typically have replaceable
tips. Tips are either steel plated or copper. Irons featuring
steel tips cost more than copper tipped irons, but are well worth
the extra expense. Copper tips degrade and lose their shape quickly
making them almost useless for fine work. The cost of standard
fixed-wattage steel tipped irons is low enough to make them worth
the investment even to the infrequent user.
Speaker Building Uses
The soldering iron is used in building crossovers
and other electrical assemblies.
- Stand - avoid burning your bench top by
getting a decent stand to hold the hot iron.
- Sponge - wipe the iron's tip with a wet
sponge prior to each use. A sponge made for soldering irons is
preferred over a household sponge.
- Clip-on heat sink - use these between
the soldering area and any heat-sensitive components to prevent
- De-soldering tool - vacuum tools are popular.
Solder wicks also work well at absorbing and removing molten
- Extra tips - these come in different shapes
and sizes. Select the size and shape depending on your use.
- Be sure to use the right type of solder
for your work. Check the solder's label before using. Never use
acid core solder for electronic work.
- · Always make sure the tip has
reached its operating temperature. Check by touching some solder
to see if it melts quickly.
- Make sure the physical connection is secure
before the solder is applied. The solder should not be used as
a mechanical means by which the joint is held.
- I like to get the iron, solder and parts
together at the same time and place. (By "part", I
mean wire, lead, pad or anything that requires soldering). This
instant merging will melt the solder onto the components at the
right spot. Removing the solder and iron quickly reduces the
chance of excessive heat buildup which can damage sensitive parts.
In essence, my goal is to use the iron to melt the solder onto
the parts. I have seen some directions that instruct the user
to heat the target parts first, and then melt the solder onto
the part using the part to heat the solder. While this method
is preferred for high heat applications such as stained glass
and plumbing, it can easily overheat sensitive electronic parts.
- The secret to great soldering - practice,
- Professional high quality soldering iron
station: upwards of several hundred dollars
- · High quality 30 watt iron plated
pencil iron with simple stand : under $50
- Consumer grade 30 watt soldering iron
: under $20
Here's a small list of other tools, both
large and small, some essential, others optional. Much can and
has been written about each, and readers are encouraged to further
research tools that interest them:
- Dust collector - This is a stationary
item specifically designed to move large amounts of air. They
are usually powered by an induction motor and are best for collecting
dust from table saws, jointers, and other large floor standing
- Shop Vacuum - A shop vacuum is a portable
device often capable of wet and dry use. It uses a small, noisy,
high-speed motor and does not have the volume capacity of a dust
collector. However, it is readily available at home centers and
department stores, and the typical hobby shop can benefit greatly
from this tool for both cleanup and dust collection.
- Clamps - No matter how many you might
have, you won't have enough! Pipe clamps are best suited for
large projects. Bar clamps exist in both heavy duty (similar
to pipe clamps) as well as light duty. Lengths vary from about
12 inches to several feet. C-clamps are extremely handy and secure,
but can be a hassle to use. One-handed clamps are much friendlier.
These usually have some sort of squeezable handle that quickly
move the jaws onto the stock. Band clamps are straps that wrap
around an item to hold everything together. Right angle clamps
hold parts together at right angles, allowing fasteners to be
inserted. This is a very handy device to use on boxes.
- Glues - regular (yellow) woodworking glue
is the most common for use on wood and wood products. Gaining
popularity as an all-purpose adhesive is polyurethane glue. This
glue expands as it dries thus requiring some care in handling.
Stock to be glued should be securely held to avoid being moved
by the glue's expansion. Epoxy is always a favorite for gluing
just about anything. And then there are the construction adhesives.
Their thick consistency makes them suitable for filling gaps.
In all cases, avoid glue fumes, and don't expose components such
as drivers to these fumes to avoid chemical reaction damage.
- Fasteners - Particle board and drywall
screws are popular for holding composite materials together.
T-nuts are often used to fasten drivers to baffles, though I've
had no problems with drywall screws. Pre-drill and countersink
to avoid tearing the stock when driving in screws. Avoid placing
fasteners too close to the edge of wood products to avoid splitting
- Framing square - Most basic boxes consist
of right angles, and a large framing square is the simplest way
to get this with a decent amount of accuracy.
Here are some beginner's tips to buying
Before buying any particular class of tool
(router, drill, etc), make sure you need this tool. Budget your
purchase and return on investment with other possible tools that
may perform the same function. Do a little research on each tool
in your price range. This article should provide you with some
basic points of interest, but ultimately, each model will have
its own features and functions to consider.
- Consider your working environment - Do
you have neighbors that might object to the noise? Do you have
allergies that might be exasperated by wood dust?
- Are there outside sources of tool time
such as those in a community center or adult education program?
- What other uses for each tool might you
have aside from your hobby?
Like all things, it often makes good financial
sense to buy things on sale. Aside from the year-end holidays,
tool sales can often be found around Father's Day. Many regional
or national chains also have frequent sales. Mail order suppliers
are common in this business, and many offer very competitive prices.
Be sure to check their return policies and shipping charges. Buying
from a local dealer may appeal to those looking for more personal
service. Many mail order and retail outlets have web sites and
advertise in leading woodworking publications.
Other factors that often affect a purchase
include brand loyalty, product quality, and availability of replacement
parts and accessories. Do some research on the manufacturer, their
service department, dealers, and repair history if these items
are important to you.
Recently, refurbished tools have become
increasingly popular. These tools are usually sold by the manufacturer
through outlet stores or through dealer special purchases. Such
tools usually have a manufacturers' warranty, but be sure to check
the warranty duration.
Internet Resources and Links
Here are some URLs relating to tools:
(Disclaimer: this information is
provided as a service to the reader, and does not represent an
endorsement of any kind of the companies represented by the URLs.)
Mail order tool sources
I've tried to keep the focus of this article
in the speaker building domain. The experienced hobbyist will
no doubt notice the vast amount of missing information. It's possible
to write an entire book on each tool, and many such books already
exist. Readers wanting to know more are encouraged to visit their
local library, bookstore, or Internet sites.
As a woodworker, I feel obligated to mention
that power tools are not absolutely necessary for speaker building
(or most other DIY projects). Craftsmen with hand tools have practiced
the art of fine woodworking long before the advent of power tools.
Some of the finest furniture made today is still made with hand
tools. Hand tools are capable of performing the same cutting,
shaping and drilling operations with no electrons present. And
like all tools, the only limitation is one's experience, patience
Hand tools offer some significant advantages
over their powered counterparts. Outfitting a beginner's shop
is usually cheaper than with power tools. Other benefits are the
lower dust levels, the absence of loud motors, the smaller floor
and bench space for tools, and more "feel" for the material.
While this article was not intended to cover hand tools, many
resources exist for those interested in learning more. Readers
are encouraged to consider hand tools in their woodworking craft.
Louis Lung (email@example.com)
We express our appreciation to
Porter Cable, and Delta Tools, for the use of their product photos.
© Copyright 1998
Secrets of Home Theater & High Fidelity
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