- Jigsaw blades for woodworking
- Blades for wood and materials made from wood
- Pictures from AEG, permission to use from www.aeg-pt.fi
- Sawing of wood, the way to go:
-
Jigsaw
has two versions: with speed limiter and without one. If you haven't
bought your jigsaw
yet, then buy one with speed limiter. It is highly
important to have slow enough speed for sawing different kind of
materials. Even the future use of the sawed material might cause
you to
drop the speed a little. There are two kind of speed limiters, one is located at the
"on"-switch and other is on top of the jigsaw. I consider the one with
the limiter on top of the machine more convenient. It will work like
charm, since the pressure of the "on"-switch will not cause the blade
to cut faster!
The reason for this is clear: when saw blade touches the sides of already sawed wood (or metal) the saw blade will get hotter and hotter. But that only happens IF your speed is too high for your job at hand. That heating may cause burned stripes to the sawed side of your wooden material.
You might have noticed that no matter how fast or slow you saw the wood being sawed will splinter at least in small amounts. You may try to stop this by using (paper) masking tape. On to that tape you should draw the line from where your jigsaw blade will go through when sawing. Usually this will reduce the splintering of the wood. Right after you have done sawing you should remove the masking tape, so that the glue from the tape won't penetrate the wood.
If this doesn't solve your splintering problem then you have to read more about jigsaw blades and select the correct blade for your job.
Sawing wood fast, no matter the quality:
Sometimes you might want to saw wood fast, no matter about the smoothness of the cut. That usually happens when remodelling, or doing something less accurate that will not show from the final result. And maby you also want to save time when you're in a hurry. This is when you should use quite rough blades.That have the distance of theet 4mm(0,157") or familiary 6,35tpi (teeth per inch)
These blades are fast but will most likely tear some chips from the wood being sawed. There are
several
different lengths available. You should always select the shortest
possible. And when sawing be sure to clamp your wood firmly and hold
your jigsaw tightly in your hands! It might be quite a surprise when
you first use rough blade! You will see that your saw has lots of power.
The faster cuts are achieved by using special "pendulum"-movement that will swing the blade
forward and back again and again while sawing. This will make the
sawing quicker, but it will not make the cut cleaner.In fact it will
rip-off more wood than without it. But it sure makes the sawing faster! - There
are couple of different sizes rough saw blades, you should select the
one that is slightly longer than the thickness of your wood to be
sawed. See the length of the stroke that your jigsaw does to get the
right length blade. You have to do little math now; if you're going to
saw 80mm(3,15") thick material and the length of stroke that your
jigsaw does is 19mm (0,75") its better to have saw blade that is
at least 80mm+19mm=99mm(3,9")long. Because the saw blade should always
go through no matter which position (up or down) the blade is. If you
have blade that is 99mm long it will barely show itself when the
"piston" is it's topmost position (99mm-19mm=80mm). The end result is
that you can't see the blade when the piston is in it's topmost
position. So you would need an
sawblade longer than 99mm(3,9"). The correct length for that would be something like the saw blade on
right. This blade has length of 105mm which is quite long for an jigsaw
blade. It still has the same 6,35tpi (4mm teeth distance). The one
below is the longest fast cutting saw blade in AEG's collection. It has
the length of huge 155mm! You should consider twice when buying this
long blades, maybe your jigsaw 
doesn't have the power to handle the load that the material thickness causes!
Sawing accurately straight:
The one most annoying feature of jigsaws is that they rarely produce straight 90°-angle to the sawed line. Usually the blade bends so that it is quite hard to get straight cuts. Some manufactures have special roller for the blade to keep the blade straight for even more deeper cuts. Usually you should use a special blade
with that roller to get accurate result. These blades are not for curves, just for straight cut. To achieve the highest accuracy, saw slowly so that the blade doesn't
have to work on its limits. This way there will be more smaller forces
against the blade that can cause it to bend. Aeg has this kind of
blade also with the length of 105mm(4,13") and the same 6,35tpi tooth
density. When you want to saw straight it also helps to have some kind
of guide so that you don't jerk your jigsaw.
Jigsaw blades for curves:
The use of sawing curves was the first real use of these jigsaws. You can easily see which blades are for curves: the are more narrow from the blade than on the end that goes inside your jigsaw. This
enables
the blade to "bend" into those tight curves. I personnaly use the
highest possible speed when doing curved cuts. This usually prevents
the splintering of the wood. There are also an special form of 
curve-blade that Aeg manufactures. These blades have sawteeths on both sides of the blade.
This kind of special saw blade makes it possible to do even square
corners. This is due to the double sided blade which enables you
to "backup" towards the useless wood, so that the blade can be turned
there.
When using blades for curves you should never use the "pendulum"-motion with them. This will make the best result. The pendulum-motion can cause the curves to be not so nice, as the blade will saw where is should have been turned...
Jigsaw blades for cleanest cuts:
To have the cleanest cut without nearly any splintering you have to know few things. First don't use the pendulum-motion at all, it was designed to make the sawing action faster, but it will not do it cleanly! Secondly use only moderate force to push the blade against the wood, it takes time and effort to get clean cuts. Thirdly use special blade that is designed for clean cuts, some say that you can always saw form beneath the board, but it is easy to make mistakes when drawing the line to sawed this way. And if all this doesn't help you can always try using masking tape as explained at the beginning.
These special blades work the opposite way than those normal ones. In fact they do saw when the blade is pulled up. So the principle is very much the same as when sawed from beneath. But these blades
have specially designed teeth's so that they wouldn't rip
the wood so much. Still if you want the cleanest result I recommend
that you try to saw from underneath. At least then when the sawed line
will show in the final result. Try this first to some waste piece, so
that your work doesn't get ruined.
It is highly important that you have the correct density of those teeth for you thickness of wood. The denser the theeths are the cleaner the cut is. But too dense teething may burn the sawed sides of your wood, so remember the rule from the first part of this article? Always at least three teeth should touch
the wood at the same time. So the distance of teeth is at most thickness/4, so if you are sawing board that is 18mm thick you will need a blade that have teeth distance of 18/4=4,5 (at most).
There are also special tables for jigsaws which help you to saw small pieces. The table is quite handy since you can see always what is happening, the "foot" of your jigsaw wont cover the view! The most high-end tables have built-in dust extraction and power-switch with emergency-stop. These tables also include some kind of jig to straight cuts.
Key points to remember:
There are some key points listed here:
-For clean cuts, use only moderate force, use special blade, try masking tape, experiment with underneath sawing.
-Fast sawing is best done with jigsaw that does pendulum-movement, use rough blade, remember the jigsaw is powerful! Be careful!
-Square sawing is best done with a special blade, use guide to prevent jerking forces.
-When sawing curves use enough speed so that the blade will cut the wood enough while turning your jigsaw.
The third and final part: "Blades for special usages and materials" will be ready after the weekend!
-The way to go
-Sawing fast
-Sawing straight
-Sawing curves
-Sawing cleaner cuts
-Keypoints to remember