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As the saying goes, there are many ways to skin a
cat. Well, to be honest, I'm not sure where that saying came
from or what it was based on. Regardless, the saying remains
true in terms of cutting circles in wood; there are many ways to
do it. You can either use a hand saw, a jigsaw, a bandsaw, a
router or even a table saw, and I am sure there are even more
ways too! Naturally, some methods may require further sanding or
work to bring the cut piece to a true circular shape.
When trying to cut a circle using a power tool or
stationary machine however, often a circle cutting jig is
needed. These can be either shop made, or commercially purchased
jigs. Having a need to cut a few circles myself recently for a
project, I grabbed a Torquata circle cutting guide to help
assist with the cutting process.
Torquata Circle Cutting Guide
The Torquata guide is really a simple kit system, based
pretty much on the same adjustable pin system you could make
yourself as a jig in the workshop, but if you are like me and
prefer the commercial made jigs, then this one is ready to use,
and quite flexible, as it can be used on several different
machines, whereas many shop-made designs might only be made for
a specific tool and cannot be readily converted for use on
another. This particular guide is designed for use on stationary
saws such as the bandsaw, radial arm saw and table saw. I don't
own a radial arm saw, so I tested it and based this review on
using the jig on my bandsaw and table saw.
The Circle Cutter is designed to cut circles from
3 inches up to 4 feet in diameter. If you want to cut larger
circles, you will need to make your own circle cutting jig as
this one reaches its limit at the 4 foot mark out of the box.
Assembly is quick and painless, and basically
involves tapping a few connector pieces into the steel channel
sections, and adding a hex nut into one channel to attach the
pivot pin. A base clamp is also included, as are instructions
for assembling it, but mine came pre-assembled out of the box,
so setup time was only about 5 minutes in total. A bag of
assorted screws, double-sided tape and other bits and pieces are
included and used for special mounting situations (which I will
outline shortly).
How Does It Work?
Long time woodworkers can probably figure out its operation
just by looking at the jig assembled. Everything is pretty
straight forward actually. I'll start by explaining the process
of cutting a circle out using the table saw and the circle
cutting jig.
Whoa! Hold your horses! Cutting a circle on a
table saw! Are you crazy? Despite some common "myths" (I guess
you could call them), cutting circles on a table saw is indeed
possible, and can be done safely too with the right procedure
and appropriate jig.
To set the jig up on the table saw, you firstly
place the base clamp in the miter slot of the saw, and align it
with the arbor of the table saw. The base clamp fits into
position via a hex head screw which screws outward from the base
clamps edge to lock in place against the edge of the miter slot.
It is designed to fit standard 3/4" x 3/8" miter slots
but there is some tolerance either way for slightly smaller or
wider miter slots. The main channel (which is the longer piece of channel) then
slides into the groove in the top of the base clamp, and is
secured by two screw and washer assemblies on either side of the
channel with the support arm channel (the shorter of the channel
lengths - which is actually made up of two joined channels)
situated close to the blade. Perhaps one of my criticisms of the
base clamp is that it can be difficult to lock it firmly enough
in place, as the adjustment screw sits under the clamp, and when
mounted in the miter slot, the adjustment screw is not really
accessible. The best you can get is a solid friction fit, and
for most tasks, this should suffice. However, if you have a
couple of miter slot stops which can be secured into the miter
slot on either side of the base clamp, you can really lock the
base clamp and jig into the slot very securely.
Now, depending on what diameter circle you wish
to cut the procedure to use with the jig differs. For circles up
to 12" in diameter, the pivot pin (located in the main channel)
is secured as close to the support arm channel as possible and
secured in place. The main channel then slides on the base clamp
left or right (closer or further) from the blade to adjust the
radius of the circle being cut. For circles larger than 12" in
diameter, the support arm is moved and positioned as close to the
base clamp as possible (i.e. away from the blade) and secured.
The pivot pin is then moved along the main channel to set the
desired radius for the jig. There are special support
situations for circles less than 6" in diameter (where a
special nylon knob is attached to the workpiece to keep fingers
away from the blade, and for circles larger than 24" in diameter
where a support leg is attached to the end of the main channel
so it isn't overhanging the edge of your saw table without
support from underneath. Instructions for both of these
situations are included in the documentation.
A 1/4 hole is drilled in the blank to sit over
the pivot pin. A smaller pivot pin is also include so your pivot
pin hole doesn't need to be drilled all the way through the
workpiece. If you do not want to drill any pivot pin holes at
all, the package comes with a plastic mounting plate with a 1/4"
hole in the middle of it. This plate is attached to your blank
with double-sided tape, and then the mounting plate sits over
the smaller pivot pin and allows the blank to be mounted without
drilling or marring the blank. This is handy if both sides of
the cut circle will be readily visible.
Once the blank is mounted to the pivot pin (by
whatever means you choose from the available options) it is time
to cut the blank. On the table saw, it is recommended that only
1/16" of an inch is cut with each rotation of the blank, so the
blade is set 1/16" of an inch higher with each subsequent
rotation. Obviously, it will take a few rotations to cut all the
way through thicker blanks, but it does do the job well, and
often with little cleanup required afterwards. Where required,
and particularly if the blank is sitting up above the saw table
by any margin, a filler piece of scrap material the width of the
gap between the blank and table surface should be clamped to the
table to support the blank underneath so it does not tilt onto
the blade and affect cut accuracy or compromise safety. I made
several blanks using the jig on the table saw, and each worked
out fine. Just be cautious of where your hands are all the way
through the cutting process as the blade is hidden under the
material for all but the last cutting rotation, and if you take your time, you
should be able to make circle cuts safely and cleanly on the
table saw using the Torquata Circle Cutter jig.
On the bandsaw, setup is pretty much the same in
terms of mounting the blanks and setting up the jig for the
different diameter circles as it is on the table saw. For smaller
bandsaws, the bandsaw table might not be as wide from the miter
slot to the edge, so additional support from the ground up to
the jig via an attached support leg (user to make and use) will
be required. Cutting a circle on the bandsaw is quicker than
with the table saw, as you can cut the circle in one pass. Use a
smaller blade (1/4" or 3/8" blade) for best results (as these
blades are designed to cut curves). More cleanup work is
required after cutting on the bandsaw as the blade leaves much
more obvious teeth marks around the edge of the circle. Of course,
if you have a decent disk or spindle sander with a 3/4" x 3/8"
miter slot, you can use the same circle cutting jig as a sanding
jig to give you a constant radius distance from the sanding
surface, and by rotating the piece on the jig, you can sand to a
perfect circular shape. This method of sanding also makes it
possible to rough cut a circle using a jigsaw and refine the
shape on the sander.
Concluding Thoughts
While it is possible to cut circles in numerous different
ways, I do like using this jig, mostly because it can be readily
attached and removed from the saws without much fuss. There is
no need to build a large, heavy sub-table for circle cutting
tasks on the bandsaw, and no need to continuously punch nail
holes into a sub-table for the pivot pin. Plus it is light and
easy to store, not taking up too much storage room. Granted, you
could make your own jig without too much drama, but if you
wanted to make it using metal components, or T-track accessories
etc, the cost could add up quite fast, and at just under AUD$44,
the adjustable circle cutter is quite cost effective, plus
offers the benefits and features to cut circles without drilling
or marring your blanks.
Unless you are cutting circles every day in your
shop (and would probably require a jig that is more permanently
fixed or solid, the Torquata Adjustable Circle Cutter should
certainly meet the needs of occasional circle cutting tasks...
Now, I have to get back to circle cutting my
third lazy susan!
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MJ-823 Circle Cutting Guide
Timbecon will also mail out to most parts of the
world
if you cannot find these items locally.
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Torquata MJ-823 Photos
All photos copyright onlinetoolreviews.com. Use without prior
written permission prohibited

T-connector that joins the track sections. The T-end provides workpiece
support near the cutting blade.

The base clamp with screw adjuster to provide a friction fit against the
side of the miter slot.

The base clamp installed in the table saw miter slot. The large pivot pin used for through-hole drilling of the blank.

Here the smaller pivot pin is installed, along with the plastic
mounting plate. The mounting plate is attached to your blank with
double-stick tape so no hole needs to be drilled in your blank at all if
you do not wish to!

The circle cutting guide installed on the bandsaw.

Cutting a circle on the bandsaw.

A support leg is attached to provide support for the other end of the
jig.

Cutting a circle on the table saw. Note no hole in the blank!

A perfect circle cut safely on the table saw... it can be done!
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