Foredom Safety Instructions for Using - Manual (Page 4)

Proper Use of Duplex Spring
Connection –
The duplex connection consists of a
double wound flat wire spring which acts
as the drive shaft or spindle inside the
duplex cover which is made with a round
wire spring. The purpose of the duplex
spring connection is to give you very free,
unrestricted control over the handpiece.
The duplex spring connection is designed
for use at angles of 45º or less from
center (see Illustration No. 4). If it is used
in a tighter radius the drive spring can be
damaged or the connection can get hot.
You can replace the drive spring (P/N
HP76) if it breaks from being used at too
tight a radius. Directions are included with
replacement springs.
Handpiece Lubrication –
The sleeve bearing in the back end of the
duplex connection should be oiled every
40 hours of use by putting one or two
drops of Foredom handpiece oil in the oil
hole (see Illustration No. 1). Use the
Hypodermic Dispenser (P/N MS10005)
which is included in the K.2293 Kit.
Another oil hole is located in the hand-
piece barrel under the palm rest. Put one
or two drops of oil in it every 40 hours
of use.
Dial Speed Control
The bench mounted dial speed control
(C.EMGX) is calibrated to correspond
to the motor RPM’s. You can set and
maintain the desired speed for each
application using the dial control.
If you use the optional On/Off foot
switch (C.FCGX), it will then start
and stop the motor at whatever
speed is set on the dial.
Preparation
The most commonly used graver is a round
graver. (A #52 graver is provided in the
K.2293 Kit. See Illustration 6.) First, prepare
the graver tang as previously instructed to
fit the 1/8
″ collet (see page 3). Next, secure
the graver by its tang in an adjustable
handle like a millgraining handle or a file
handle to provide a safe way to hold the
graver while grinding its cutting edge
(see Illustration 5, Fig. A).
Place a container of water next to your
bench grinder wheel to use as a coolant to
keep the graver cool while grinding. This
will prevent the loss of the temper (hard-
ness) of the steel due to overheating. While
grinding the graver, repeatedly dip the
graver into the water. It is a good idea to
dip the graver in the water after each grind-
ing pass. Always wear eye protection
when using any grinding tool.
Grind away the top of the graver, always
grinding from the front to the back (tip to
the handle). Grind in a smooth, continuous
motion. Grind away a small amount with
each pass. (Remember to dip the graver in
the coolant after each pass.) Grind a taper
into the graver approximately .08
″ (2mm)
high at the tip, then back approximately
3/4
″ (20mm) to the top of the graver. (See
Illustration 5 Fig. B.) Remove any burs on the
sides of the graver left by the grinding.
The face of the graver should be sharp-
ened at the bench with an oil stone (an
Arkansas hard stone is recommended).
The graver can be held by hand for this
operation, or in a graver sharpening fixture
(See Illustration 7) available through most
jewelry supply tool stores and catalogs.
The angle on the face of the #52 round
graver can vary depending on the
application and what you are accustomed
to using. The most common angle used is
45°. Move the graver back and forth
slowly along the length of an oil stone
while holding the graver at a 45° angle.
Do this until the face is established across
the width and height of the graver tip.
(See Illustration No. 5, Fig. C.) Remove
graver from handle and secure in
handpiece chuck.
Set the impact adjusting ring to a medium
to hard impact. To create a bead, place
the graver about 1/32
″ (.75–1mm) away
from the inside wall of the bearing. Raise
the graver so the bottom edge is at a 45°
angle from the surface. (See Illustration
No. 8.) Do not push, apply just enough
pressure to keep the graver tip in the
metal. This will take some practice, and
may require breaking old habits. With the
graver in this position, set the speed
control at 2,200–2,400 S.P.M. For even
better results use an optional on/off foot
switch. Let the hammering action of the
handpiece do the work.
Illustration No. 5
Fig. B
Fig. A
Fig. C
20mm
2mm
Illustration No. 4
Center
Line
Illustration No. 6
#52 #3 #40 #2
Round Onglette Flat Bevel
Illustration No. 7
Bead Setting with the PowerGraver Handpiece
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