Recent Cool Tools columns
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The saw frame is typically the first purchase made by the
aspiring jewelry maker. It is the most important tool to acquire and master because
sawing and piercing are basic operations for all metalwork. It is important to
practice sawing without a thought of a finished piece until you’re confident
you can follow a line, turn both inside and outside corners, cut along complex
curves, and cut all thicknesses of sheet in all metals.
The best way to start is to choose a saw frame, get a few dozen blades in
a range of sizes, and buy five or six small sheets of metal. I suggest aluminum,
copper, brass, and bronze because they all saw differently. Start with 20-gauge
and work down to 18. Then try 24 or 28-gauge. And trust me — save the silver
for later, when you know what you’re doing.
I’m including practice patterns and instructions for cutting them out.
Follow the photos for learning to thread, hold, and use your saw. Don’t
freak if you break a blade — everybody does. You may find you love to saw
or you may find you hate it. If you hate it, get over it — unless you really
want every piece of jewelry you make from now on to be standard, mill-cut rectangular
or square!
 Purchasing a Frame
There are two types of frame: adjustable and stationary. Most makers prefer the
adjustable frame because short lengths
of broken blade can be strung and used until completely
worn out. This is a good feature when you’re new to the saw because you’ll
probably break many blades when learning.
A stationary saw frame will only accept full length blades, so these are best
purchased by an experienced maker. Once you get the knack of sawing, you’ll
only break a blade occasionally — unless it’s a dreaded, bad-blade-karma
(BBK) day, in which case you should go do something else in the shop for a while.
Recognizing and accepting that you’re having a BBK day is humbling but
also one of the most important things to learn about sawing. Everyone has them
once in a while, so don’t think it’s just you.
Some frames allow the blade to be rotated in an arc away from the cutting line.
This allows you to relocate the back bar of the frame away from the kerf (the
cut, more on that later) and to use a larger piece of sheet. This kind of frame
is handy if you cut strips or lots of cuff bracelet blanks.
Saws come in several standard throat depths ranging between about 3" and
11" in depth. A 4" frame is a good starter size and will allow you
to cut typical sheet sizes available from most suppliers. If you’ve never
sawn before, look at this graphic and familiarize yourself with the parts and
mechanisms of your frame.
Practice Pattern
Photocopy this pattern at 100 percent. If you’re right-handed, saw in the
direction of the Right arrow. If you’re left-handed, saw in the direction
of the Left arrow.
Download the pattern in PDF format.
 How Blades Work
Sawblades don’t really cut. They actually weaken and then chip small particles
of metal away. Take a close look at a blade directly at the teeth (use a magnifier
if you need to) and you’ll see they alternate left and right in a predictable
pattern called a set. This arrangement allows the chips of metal to fall away
on both sides of the blade. The distance from the outer point of the right teeth
and the outer point of the left teeth is the blade thickness, and will determine
the width of the kerf — or “cut” opening you make with the
blade. Finer blades make a narrower kerf.
What You’ll Spend
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3" sawframes run between $10 and $35 depending on where they’re
manufactured and who you buy them from. Try to buy a quality, hardened tool steel
frame with a contoured wood handle.
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Blades average between $1 and $6 a dozen — again, you get what you pay
for. When you’re learning to saw, start with good blades even though you’ll
destroy them. Good ones usually break only because of bad technique. You can
learn to correct your technique, but you can’t correct poor materials,
so why struggle with something you can’t fix?
Threading the Saw
Sawframes are engineered to hold the blade under tension. To
create tension, a series of thumbscrews, pads, and washers allow minute adjustments
to the frame depth, length, and the amount
of pull on the blade. Here is how to thread the blade properly into your frame.
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1. Pick up a blade. Look at the teeth. Make sure they face you and angle
down, like a children’s drawing of a Christmas tree. |
2. Hold the blade next to the frame for a visual comparison. The frame
should be roughly set so it’s slightly taller — about 3⁄4" — than
the total length of the blade. |
3. Insert the top of the blade between the frame and
the pad with the teeth facing out and down. Ensure the blade spine is parallel
to the back bar of the saw frame, and the very
top of the blade is touching the top of the opening at the set screw. Tighten
the top set screw to hold the blade firmly. The
bottom of the blade should float freely just above the bottom
set screw and pad. |
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4. Insert the top of the saw frame, with the blade facing up, into the
mandrel hole of your bench. Alternatively, position the top bar of the frame
against the lip of the bench. |
5. Push slightly against the bottom of the frame handle with your hip,
shoulder, or sternum. You will see the bottom bar of the frame move closer to
the bottom of the blade. Keep pushing gently until you can capture and insert
the blade between the pad and the frame. |
6. Tighten the bottom set screw securely while maintaining pressure on
the frame. |
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7. Release pressure on the frame slowly. |
8. Verify the blade is tight by “pinging” it with your fingertip.
It should make a clear, musical sound. If it doesn’t, you’ll have
to adjust the frame to increase pressure on the blade. |
9. With the blade still in position, loosen the frame set screw. Hold
the frame in your hand with the back of the frame against the heel of your hand.
Pull down on the bottom bar with your fingers to increase tension on the blade.
Tighten the frame set screw and test the ping of the blade again. It should be
high and clear. |
Choosing a Blade
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The more intricate
or curvey the cut, the finer the blade — unless
your sheet is very thick.
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The blade should have a minimum of three teeth contacting
the metal when sawing. Too few teeth contacting the metal will result in choppy,
jumpy motion. Too many teeth may result in broken blades. To compare, hold the
blade spine against the sheet and look at them both from the side to see if the
metal is three teeth deep.
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When you drill a pilot hole for inside piercings, ensure the blade has enough
clearance to move freely in the hole.
Practice Makes Perfect
You will cut the entire square of aluminum into tiny shapes and strips by following
the pattern in sequence. If you’re right-handed, the waste side of the
sheet should be to the left, and vice versa. By the time you saw all the lines
of the pattern, you’ll have learned all of the essential sawing maneuvers.
Try to stay on the lines, not to one side or the other. After you’ve cut
the entire square, move on to the next metal square using the same pattern.
Try the 18-gauge copper with the same pattern and a 1/0 blade. After that,
try 20-gauge bronze with the 2/0 blade, and finally
24-gauge brass with a 6/0 blade. Note the increase in hardness as you cut the
different metals — hopefully, your skills will advance at the same rate
of difficulty you’ll have sawing them. If not, practice until they do.
Attaching
the Pattern to Metal
There are many ways to transfer a design to metal, but I find this method the
easiest:
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10. Photocopy the drawing, trim the excess paper,
and coat the back of the paper with a thin coat of rubber cement. Let the cement
dry.
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11. Brush a thin coat of rubber cement on clean,
dry metal and let the cement dry.
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12. Carefully roll the paper onto the metal, pressing
the dried cement together so it bonds. Start at one edge and continue across.
Be careful not to wrinkle the paper as you roll it onto the sheet. |
Making your First Cut
Thread a 2/0 blade into your frame. Attach the pattern to the
20-gauge aluminum. Position the metal on the bench pin according to whatever
your dominant hand is. Take a deep breath and relax your hands and arms. Exhale.
If You Break a Blade
Go ahead and get the swearing out of the way. Pick up the broken blade sections
to see if any are long enough to reuse. Save what you can, and dispose of the
rest — you don’t want steel mixed in with your scrap. I keep an envelope
in my bench pan just for useable, broken blade sections.
If the blade has snarled in the metal, unscrew one of
the frame set screws and try to work the blade loose. If it is hopelessly snarled
(extremely rare) and you can’t budge it, unscrew all of the set screws,
remove the saw frame, and pull the blade out of the kerf with toothed pliers.
Throw it out; it will probably be bent or twisted beyond repair.
Thread a new blade and try again, but make sure the sheet hasn’t warped,
bent, or twisted, and that the kerf is clear and open — or you’ll
end up killing another blade.
Special Scenarios
Once you’ve sawn the straight, gently curved and tightly
curved lines without breaking a blade, don’t get cocky — you’ll
need to saw the inside and outside corners next. These are the hardest cuts to
master, especially in thicker gauges or harder metals.
The most important tip for these sawing scenarios is to pivot the metal in place
around the blade at the same time you’re moving the saw. Remember, the
blade does not cut, it chips, so move the saw up and down in short strokes and
pivot the corner point of the cutting line around the blade until the teeth are
facing the direction you want to saw next. Sharp direction changes are very difficult
for everyone, so don’t get discouraged.
Cutting Out a Hole
Cutting a hole is easy once you figure out which direction to saw
in. You’ll want to drill the pilot hole near the cutting line in a position
that allows you to transition efficiently and directly into the cutting outline
without a sharp change of direction.
If you’re sawing a complex pierced or fretwork design, saw
the innermost holes first, and then work out toward the exterior of the design — that
way, the intact, exterior metal supports the fretwork.
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18. Because I’m right-handed, I want the “hole” I’m
sawing to be to the left of the blade. If you’re left-handed, do the opposite.
Make a dot with a marker near the cutting line.
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19. Centerpunch the dot on a steel block, and
drill it with a number 54 bit (a good, all-purpose size for most blades).
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20. Unscrew the bottom set screw and string
the metal onto the blade with the pattern facing away from you (toward the top
of the frame). Slide it all the way up the blade.
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21. Thread the bottom of the blade as usual.
Make sure the blade is under tension. Slide the metal down to the bench pin and
start sawing toward the cutting line in a gentle curve. Once there, continue
to follow the outline. Remove the completed piece from the saw by releasing the
bottom set screw and sliding the metal off.
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Cool Tools is a regular feature of Jewelry Artist. If you have a tool you would
like featured, a useful tool modification, or interesting bench trick to suggest,
or, if you'd like to join our studio of experts, contact Helen Driggs, Managing
Editor, Jewelry Artist, 300 Chesterfield Parkway, Suite 100, Malvern, PA 19355,
or hdriggs@interweave.com, subject line "Cool Tools." Please include your complete
contact information with all submissions.
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