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Beginner's Guide to the Scrollsaw
While this brief guide only scratches the surface of the existing knowledge and techniques regarding the tool known as the scroll saw, it provides a quick explanation of the key
concepts of this special tool. A Bit of History
The evolution of the scrollsaw is linked to the rise in popularity of frework -- the sawing of intricate shapes from wood. Although there are examples of fretwork-like
decorations on early Egyptian, Greek, and Roman furniture, these were probably carved or cut with a knife. It wasn't commonly practiced to saw delicate wooden shapes until the late 1500's, when a German craftsman (most likely
a clock maker) devised a method for making fine, narrow blades.
Soon thereafter, a Parisian began to develop specialized hand tools for cutting these intricate designs. He designed a U-shaped fret saw which was
originally known as a Buhl-saw (Buhl a corrupted pronunciation of the man's name) very similar to a coping saw. As Mr. Boulle's work gained notoriety, the craft was legitimized and quickly spread to Italy within a generation.
Fretwork was introduced to America in the mid-1800's as Sorrento wood carving. Sorrento is so named because of the area in Italy that it was most popular. By the 1860's, the first mechanical fret saws -- called
scroll saws -- began to appear in the U.S. And so a great art form and hobby were born. Today there are over fifty models of scrollsaws available with many options.
Safety First
As far as powered woodworking tools go, the scrollsaw is among the safest.
However, do not be fooled -- ALL power tools can be dangerous.
You'll want to wear your safety goggles as usual and have good ventilation and a mask. Keep your fingers clear of the blade and mind the reciprocating arm
of the scrollsaw as it can easily break a finger or even worse.
Most scrollsaws nowadays are equipped with a spring in the arm so that when a blade breaks, the broken top-half does not come shooting down into the project or
your hand. Regardless, it would be nice to know whether your saw will react this way or not.
Use the workpiece guard to hold down your project snugly, while still allowing it to move freely. As you become more
experienced, you may decide that the guard is not necessary or that it even gets in the way. As a beginner, you should use the guard.
The scrollsaw is a great tool for young woodworking students to learn. It cuts
slowly, so there's less "quick-thinking" to do. If you ever get stuck, you can just shut the power off and relax. You should always remain alert while working with any machine -- and good lighting is essential.
Choosing a Scrollsaw
There are many features to consider
when choosing a scrollsaw which you might not think about before you know the intracacies of the hobby. Once you DO know the "ins and outs" of scrolling, you may quickly wish you had thought of these things prior to
your purchase:
Blade Suspension -- EVERY scrollsaw project will require you to remove one end of the blade from the machine and "thread" it through the work piece to start a new cut. Because of this aspect of
scrolling, you want to be able to change the blades quickly and easily.
Quick-release blade clamps and a forward-mounted tension adjustment mechanism makes it much easier to both change blade types and to thread a blade
through the stock for making inside cuts -- something you will have to multiple times for any one project.
Two types of blades -- All scrollsaw blades have several characteristics in common, but there are also many different
varieties of blades. Here we'll only discuss the general features. You should not listen to any one source to make up your mind. You should try many kinds of blades and decide for yourself what works best for you.
All scrollsaw blades are thin. Really thin. Some look like pieces of human hair! All blades also have numerous teeth, cutting surfaces, just like any cutting tool must have. The number of Teeth Per
Inch (or T.P.I.) depends on the purpose of the blade. A general rule of thumb to go by is the more TPI, the smoother and more accurate the cut, but also the slower and more fragile.
Scrollsaws will accept one of two types of blades.
* Pin-End blades
* Plain-End blades (flat blades)
Plain-End blades are what you would imagine when thinking of a generic
cutting blade. This type of blade is totally flat and is pinched in place between the jaws of small clamps on the scrollsaw. One clamp is above the work table of the scrollsaw, one is below the table, and the blade is
threaded through a cut in the table so it may reciprocate up and down freely.
The Plain-End blades are more widely available and are considered the standard for most long-time scrollsawyers. Many different varieties of
Plain-End blades are available from many different stores and probably always will be -- you'll always be able to get them.
Pin-End blades, on the other hand, have a tiny cross pin in each end. The cross pin is the
main difference between the two types of blades. These pins rest in a hook-like holder. The upside and main selling point of Pin-End systmes is that they are much easier and quicker to change.
The downside to
Pin-End blades is mainly two-fold: there is less availability AND, as you get more ambitious with your choice of projects, the Pin-End blades (because of the pins) may not be able to be threaded through very small holes
required by these projects.
Seeing is believing -- Never buy a tool without seeing it run first. A well-balanced tool of any variety will not vibrate very much, if at all. Your scrollsaw should run smoothly and
quietly. If there is a blade installed, it should appear as a crisp, thin black line as it goes up and down -- if it is blurred, something is out of whack (maybe it is easy to fix...maybe it is a permanent flaw).
Variable speed or not? -- Some people will swear that you must have a variable speed control on any worthy scrollsaw. As we've said before with regards to blades, you should consider and make your own mind up. Some
projects may require a slower cutting speed than others.
A high speed (1,200 - 1,800 Strokes Per Minute) may be needed to cut a very hard wood or get a fine cut. A low speed (400 - 800 SPM) may be used to cut a softer
wood. A variable speed will allow any speed in between. As a beginner, you may make your decision based on cost.
Some saws have one speed, others have two, and still others are totally variable. It is our
opinion that a two speed scrollsaw -- slow and fast -- is the best choice for most the beginner who is concerned about cost. This sort of saw will give you what you need to get by at low cost.
Throat Capacity -- This
is the amount of space between the cutting edge of the blade and the front of the reciprocating arm swivel or mounting point. The throat capacity determines how large of a workpiece the saw can handle. As you begin to
push the workpiece into the cutting blade, it starts to move toward the back of the saw where the arm swivels. At some point, unlike on a table saw, the wood will not be able to go any farther. This is inherent in the
design of ALL scrollsaws.
A great throat capacity is about 18". Unless you are a true professional with unique needs, you a saw with 18" will seldom cause a problem. It should be noted, however, as many
people think they can cut any type of workpiece on a scrollsaw, it is a specialized tool.
Stand-alone or Table-mounted? -- Both usually have the same throat capacity and features. The advantage of stand-alone models is
their (usually) built-in dampening effect. Vibration is reduced due to the design of the stand (or at least should be). Table-mounted saws may vibrate more, depending on what they are mounted to -- if you opt for table
mounting keep this in mind.
Optional Accessories
You can go hog-wild buying all sorts of extras for your rig. As you might imagine, some things are more useful than others. Some are gimmicks and
some have actual value.
Blade releases / quick clamps -- In the past, most scrollsaws required a hex key or special wrench to operate the blade clamps. Today, more toolmakers are offering models already equipped with
blade clamps you can release or tighten with your fingers. If your saw isn't already fitted with these, you can probably update as many aftermarket parts are available. Highly recommended!
Blowers -- Just like it
sounds, these devices are air hoses that can be positioned to where the blade contacts the wood stock, blowing away the sawdust that builds up. Not really necessary, but expect a workout for your lungs if you don't have
one. It's handy.
Magnifiers/Lights -- A magnifier and lamp are often combined and both are very useful as you get into more ambitious projects. This accessory magnifies the pattern lines making them easier to
follow and cut. Head-mounted units are also available. Lights are more important than the magnifying aspect. Good lighting is essential!
Foot-activated Power Switches -- These devices, as their name so
aptly describes, sit on the floor and allow the operator to shut the machine down by simply tapping the toe. Tap it again to start back up. They generally are adaptable to any machine. Super convenient.
A Little About Blades
We've already discussed the two main blade types,
Pin-end and Plain-end. Now let's talk about which kind of blade to use for specific types of woods and projects.
We've already discussed "T.P.I." (teeth per inch) -- and depending on what you're cutting, the
optimum TPI will vary. The general rule, again, is the fewer the TPI, the more aggressive and rough the cut is going to be, while the more teeth, the slower and finer the cut.
Blades are designated by numbers, odd
numbers: 1's, 3's, 5's, etc.. The higher the number, the fewer the TPI . Hence, No.9 blades are for hard woods and aggressive cutting.
There is no such thing as a concrete blade guide which will tell you exactly
which blade to use for each application -- it's really up to the user, but for a quick example:
* 1/4" birch = No.3 blade
* 1/2" poplar = No.7 blade
* 1" oak = No.9 blade
As you become more accustomed to the scrollsaw, you will learn the blades. Here we are giving you the general information, but while a No.7 blade might be recommended by
one scrollsawyer for 3/4" oak, another scrollsawyer will tell you a No.5 is better, and yet another a No.9 or 12.
Use the info herein to get you started, but we highly recommend you experiment. (You may want to
try our Intro Pack of Reverse-Tooth blades to get a good feel for the numbering system.)
Standard Blades -- Standard blades have teeth in one direction.
Reverse-Teeth Blades -- Reverse-teeth blades, like the Flying
Dutchman we offer, have most teeth in one direction just like a standard blade, but they also have a few teeth going in the opposite direction so when the blade slashes back up through the wood a smoother cut is made. These
blades will cause you a little less sanding time.
Spiral Blades -- These blades have teeth all around the blade. Imagine a cylindrical shredder that can cut in any direction. They sound great, but problems are
often reported such as: breaking, difficulty in controlling cut, dulling quickly, and poor cut. Try them for yourself maybe.
Regardless of which blades you choose, you should make the decision as to which are
best for your style of scrolling. You don't need a huge supply of blades to make nice projects. If you're just starting off, try a dozen of No. 5's, maybe some No. 9's, perhaps a dozen No. 12's, and a few No. 3's.
A selection like this should be plenty to do any job a beginner would attempt.
There is a lot to know and learn about scrollsaw blades, so just jump in and get started!
A Few Quick Tips
* A makeshift blower can be made out of an aquarium air
pump which can be obtained at garage sales or a local pet store relatively cheaply. Put a soft metal (copper) tube at the end of the hose (where it will blow from) and crimp the end in order to increase the velocity of the airflow
exiting.
* Adjust the hold-down so it applies enough pressure to keep the wood on the table, but not so much that you can't feed the stock through.
* Before cutting, turn on the saw and
make sure the upper arm isn't hitting anything. Make a test cut to see that it cuts properly.
* When working with hardwood or thick pieces, set the saw at a higher speed. When working with thin or
softwood, use a slower speed.
* The feed rate is VERY important. DO NOT push the wood through too fast. Work slowly with a gentle pressure. If your blade is bowing under the pressure, you're
moving too fast!
* For cutting straight lines, you can clamp a guide fence onto your saw's table and feed your stock by it. This works great!
* The best tip of all: Take your time and enjoy the tool -- have patience! |
