Back to Ganoksin | FAQ | Contact

Selecting appropriate saw blade size


#1

How do I know what is the correct size of saw blades to use to cut
wire (for jump rings) and for metal (to cut out shapes, etc. Right
now I am making some twisted wire oval and triangle jump rings.

Thank you. Jaynemarie


#2

From the Contenti Company web site

Actually they have a lot of good charts at:

jena


#3

Jaynemarie, Following is a paper I wrote sometime back for use in my
classes. It may be too much for to answer your simple question, but
you may find the useful. Cheers, Don in SOFL

SAWING AND PIERCING
By Donald Dietz, March 2004

Knowing how to saw properly is a very important and basic function
in jewelry fabrication. The rules are fairly simple but there is a
specific regimen to follow to be successful. Following are eight
basic rules:

By looking at the blade from the side you will see the teeth slant
down approximately 45 deg, Hold the blade with the teeth edge up and
the teeth facing towards you. With the opening of the saw up, insert
the blade into the top stay as far as it will go and tighten the
thumb screw. Adjust the length of the saw frame by loosening the
thumb-screw on the bottom and sliding the frame apart until the lower
end of the blade (the part closest to you) is just at the edge of the
top edge of the bottom stay. Tighten the frame thumb-screw. With the
top of the saw frame against the edge of the table, push in gently on
the handle, place the lower end of the blade into the stay
approximately at the mid-point and tighten.

Test the tension of the saw blade before sawing. A loose blade breaks
easily and will not cut properly because of the ‘sag’ in the blade,
while a blade that is too tight will break due to the tension. When
plucked, the blade should make a medium pitched ‘ping’. A high-
pitched - ‘tink’ is too tight while a low ‘twang’ is too loose.

Choose a blade fine enough to have at least two teeth (but not more
than three) within the thickness of the metal. A helpful chart is
provided below to use as a guide for metal-gauge-to-blade size.
Experience will teach you that there is no use trying to saw 16ga
sheet with a 2/0 blade because it will take forever. On the other
hand, using a number 2 blade to cut 24ga sheet will cause ripping and
tearing and leave sharp edges.

Generally, a blade choice is influenced by the intricacy of the line
to be cut. For example, when cutting curves, or sawing intricate
designs, choose a blade one number finer than one normally used for a
specific gauge metal. This will give better control and reduce the
amount of filing after sawing.

When sawing a straight line, tilt the saw frame slightly forward and
make long even strokes. The kerf helps hold the blade straight.
Otherwise;

Hold the saw frame perpendicular to your body and bring your work to
the saw. When sawing a curve or making a 90-degree turn, hold the
saw frame vertically and make short up and down strokes that do not
move forward. Keep the saw aimed away from you and turn the metal
into the blade. Do not turn the blade into the metal unless it is
moving up and down, otherwise the kerf will bind and break the blade.
To saw a circle, turn the material to the saw instead of trying to
saw around the material. Should the blade bind in the kerf, let go of
the metal and allow the piece being sawn to twist and find its own
place. This should release the bind and you can continue sawing.

The up and down motion should come from your elbow (not your wrist).
Your wrist should remain locked but your handgrip on the handle
should be light – no white knuckles. Your thumb should be over your
index finger.not sticking up as that tends to make the saw pull to
the side. Be gentle!

Lubricate the blade with wax, Bur-life, light oil, ear wax or even
spit; it will give longer wear and ensure smooth, easy cutting. Some
advocate lubricating the back of the blade to preclude swarf
accumulating in the teeth. The wax melts from friction and provides
adequate lubrication.

To pierce, it is necessary to first drill a small hole in an area
where it will not show in the finished design. In the chart below,
use the drill sizes shown on the right to drill a hole for the
indicated size of blade. With a center punch make a small dent at the
point you want the hole and drill it. With the design face up, feed
the blade through the hole from the bottom of the plate and secure it
to the top stay of the saw frame. Take your time and saw as close to
the design as possible to reduce filing time. If the surface will be
textured or domed, pierce AFTER texturing or creating the dome to
preclude distortion of the shape or design. (over)

REMEMBER: Sawing off a piece of metal saves precious metal for other
uses or to melt down and remake into plate or wire. Filing or sanding
the metal results in a pile of metal dust good only to a refiner

Metal

B&S Gauge       Blade size      Drill size for piercing

26 plus         8/0             80
24-26           7/0             80 
24              6/0             79
22-24           5/0             78
22              4/0 or 3/0      77 or 76
20-22           2/0             75
18-20           1/0             73
18-20           0               72
18-20           1               71
16-18           2,3,4           70,6, 67
16              5               65
14              6               58
12              7 or 8          57 or 55

Think of blade size as a cross ? with 0 at the center of the cross.
Single digit blades ( 0 through 8) are coarse cut and all above the
cross bar while -/0 digit blades (1/0 through 8/0) are fine cut and
all below the cross bar.

COARSE
8
7
6
5
4
3
2
1
0
0/1
0/2
0/3
0/4
0/5
0/6
0/7
0/8
FINE


#4

You must have "at least TWO teeth of the blade on the metal at all
strokes. Figure it out, Gauge vs teeth.

Stephen Wyrick, CMBJ CSMP
Gemmologist


#5

Hello Jaynemarie,

Use the smallest size of blade you have. You may have to use a
magnifier to see the teeth. You want the blade that has the finest
teeth. I use flush cutters to cut my jump rings. I have a chart of
saw
blade sizes, in my shop. I will get it and send it to you.

Dale


#6

Thanks Dan, for posting the info about the jewelers saw blades and
use. I went to get my info off of my external drive and it has
stopped working. I just hope I haven’t lost everything on it, which
would be all my jewelry notes, genealogy notes, pictures, etc. I
have emailed the manufacturer but have heard back yet.

Veva Bailey


#7

Hello Jaynemarie,

When I began learning to make jewelry many years ago, my instructor
suggested to buy 4/0 blades. I have not changed since. I still use
4/0 for almost everything. There are time when I will use a finer saw
blade for detailed work or a more coarse blade for very thick metal.
The exact size for what comes with experience. With regards to
cutting jump rings, the larger the saw blade the smaller the diameter
of your finished jump ring. Experiment a little, buy some different
sizes and see what works best for you. If you have Rio Grande’s 2009
catalog (tools and equipment), on page 84 there is a chart that has a
suggested blade size depending on the thickness of the metal. I hope
this helps.

Best of luck,
Steven Brownlee


www.StevenBrownlee.com


#8
With a center punch make a small dent at the point you want the
hole and drill it. 

I have only one tiny quibble with Don’s excellent paper, which is the
above… Since jewelry sized work very often can’t handle center
punching because of issues with stretching and distortion when you
hammer on it, use a round bur instead. Use one that’s around the same
size or a bit larger than your drill bit, and just pop a little divot
in the metal, like a center punch would do. A center punch is fine
when it works, but you just can’t use it in many spots in jewelry
making…

http://www.donivanandmaggiora.com


#9

John,…thanks for pointing out that important omission of using a
burr to make a drilling dent. I will add it to my paper
immediately!!!

Cheers,
Don.