GRS Magnum User manual

PAGE 1 of 4 LIT-258
ADJUSTING THE HANDPIECE
To position the hose, loosen the locking ring a little. With the locking ring slightly
loose, the handpiece body and knob can be turned independently. Position the
Quick Change holder with the graver “point” down. Rotate the knob until the
hose position is comfortable, then tighten the locking ring.
The length of the handpiece can be extended a little by unscrewing the knob
and body even more. NOTE: When the handpiece length is extended, a loss of
power may occur, depending on the type of work being done.
ATTACHING A NEW HOSE
Loosen the locking ring (FIG. 1). Remove the knob from the handpiece. Remove
the hose by cutting it off close to the knob. With a small punch, push the hose /
brass tting back into the knob body. Remove the brass tting (#044-031) from
the hose. Feed the new air hose through the hole in the knob (FIG. 2). Insert the
brass tting into the end of the new hose, making sure it is fully seated.
If needed, lubricate the tting rst to help it slip into the hose easier. Then apply a
small amount of water or oil around the outside end of the hose next to the brass
tting and pull the hose back (FIG. 3) into the knob until you see the tip of the
brass tting protrude through the side of the knob. This must be an air tight t, so
a bit of force may be needed (a few pounds of pressure, at least).
MAINTENANCE
Keep the Magnum handpiece clean on the inside. Problems will occur if oil or
moisture gets into the handpiece, especially on the piston. If you notice a loss
of power or erratic performance, rst check if the receiver (chuck) is tight in the
handpiece body. Using a crescent wrench or pliers with a graver inserted in
the QC Holder, gently tighten receiver clockwise (FIG. 4) If erratic performance
continues, then disassemble and clean the handpiece. To disassemble the
handpiece, use the crescent wrench or pliers to grip the graver (FIG. 4) and
turn it counterclockwise to loosen the chuck retainer.
After loosening, turn the chuck retainer out with your nger tips (FIG. 5). As the
chuck is pulled out, there will be a spring and piston that follows. Loosen the
locking ring and remove it (FIG. 6). Grip the knob and turn the handpiece body
counterclockwise until it is out of the knob body (FIG. 7).
Now, with the handpiece disassembled, clean the parts with a non-residue
solvent like denatured alcohol. Make sure the holes in the handpiece body
are clear from dirt and debris. DO NOT get moisture down the air hose. If this
happens you will need to clear and dry it before reassembly.
Before reassembly, make sure every thing is completely dry. DO NOT OIL
INSIDE THE HANDPIECE. NO lubricant is required. Lubricant will actually
decrease performance!
Magnum® & Magnum® Airtact Handpiece
INSTRUCTIONS • #004-940, #004-940-OVAL , #004-941, #004-940-ATSS & #004-957SS
Standard Spring
Normal Operating Range 18-22 psi (1.2-1.5 bar) /
1400 - 3400 spm
Recommended Initial Setting 19 psi (1.3 bar) / 2700 spm
PSI: Pounds per Square Inch • Bar: Unit of Measurement • SPM: Strokes Per Minute
LOCKING RING
Loosen first
FIG. 1
Lubricate end
slightly with
water or a small
amount of oil.
LOOSEN
TURN COUNTERCLOCKWISE
TIGHTEN
TURN CLOCKWISE
LOCKING
RING
FIG. 2
FIG. 3
FIG. 4
FIG. 5
FIG. 6
FIG. 7

LIT-258 PAGE 2 of 4
Magnum® Handpiece PARTS LIST #004-940
REASSEMBLY NOTE
There is an O-ring inside the knob that makes getting the handpiece body to
thread a little difcult when reassembling. Use a very small amount of synthetic
lube or non-stick grease and create a thin lm around the OUTSIDE of the
handpiece body between the threads and the end (FIG. 8). See “Adjusting
The Handpiece” on p. 1 of this literature sheet for adjusting graver and hose
position.
QUICK CHANGE HOLDER HINT
Synthetic Lube or non-stick grease on the shaft of a quick change holder will
make them easier to slip in and out.
NOTE: Do NOT use
petroleum based oils -
USE ONLY Synthetic
oils. Fossil oils can
damage the O-Rings.
PART NO. DESCRIPTION
002-127 O-RING
002-605 HEX WRENCH, 5/64"
004-803 QC HOLDER
022-072 BARBED FITTING FOR 1/4" X .040" WALL TUBING
022-946 O-RING
022-947 O-RING 1mm X 12.5mm
022-948 O-RING 70 DUROMETER
044-020 ANVIL
044-021 THREADED RETAINER
044-022 TOOL RECEIVER
044-023 SPRING COMPRESSION
044-507 PISTON
044-025 HANDPIECE BARREL
044-026 LOCK NUT
044-028 TUBING, PU CLR 0.250" O.D. 0.160" I.D
044-029 TUBING, PU CLR 0.250" O.D. 0.170" I.D.
044-030 PALM KNOB
044-031 HOSE RETAINER
Very Light
synthetic grease film
FIG. 8
Hollow end
Very Light
synthetic grease film
Optional upgrades:
#044-507
Tungsten Piston
#044-163
Shortened Barrel

PAGE 3 of 4 LIT-258
Oval Magnum® Handpiece PARTS LIST #004-940-OVAL
Magnum® Airtact Handpiece PARTS LISTS #004-940-ATSS
PART NO. QTY. DESCRIPTION
002-127 2 O-RING, 0.750" O.D. 0.610" I.D.
002-605 1 WRENCH, 5/64 ALLEN
004-803 6 QC HOLDER
022-072 1 TUBE COUPLING, 0.170" I.D.
022-946 2 ORING, 0.285" O.D. 0.145" I.D.
022-947 1 ORING, 14.5mm O.D. 12.5mm I.D.
023-024 8 SHCS, #2-56 x 0.19" S/S
023-029 1 FITTING, M-0.063" I.D. TUBE F-LUER
044-020 1 ANVIL (MAGNUM)
044-021 1 THREADED RETAINER (MAGNUM)
044-022 1 TOOL RECEIVER (MAGNUM)
044-023 1 SPRING COMPRESSION
044-507 1 PISTON, MAGNUM
044-025 1 HANDPIECE BARREL (MAGNUM)
044-026 1 LOCK NUT (MAGNUM)
044-028 1 TUBING, PU CLR 0.250" O.D. 0.160" I.D.
044-029 1 TUBING, PU CLR 0.250" O.D. 0.170" I.D.
044-031 1 HOSE RETAINER
044-110-D1 3 PALM PAD, E2 #04
044-110-E2-06 3 PALM PAD, E2 #06
044-110-E2-08 3 PALM PAD, E2 #08
044-110-E2-10 3 PALM PAD, E2 #10
044-126 1 FITTING, 0.094" O.D. 0.063" I.D. x 0.35"
044-130 1 TUBING, PU CLR 0.125" O.D. 0.063" I.D.
044-162SS 1 PALM KNOB (MAGNUM)
044-204 2 0.500 DIA BLACK SHRINK TUBING
044-219 1 INLET INSERT FOR MAGNUM AT KNOBS
044-231 1 BRAIDED SLEEVE, 0.375" O.D. NYLON
PART NO. DESCRIPTION
002-127 O-RING
002-605 WRENCH, 5/64 HEX-WRENCH
004-281 HOSE RETAINER
004-803 QC HOLDER
022-072 BRASS BARBED FITTING FOR 1/4 X 0.040 WALL TUBING
022-946 O-RING
022-947 METRIC O-RING 1mm X 12.5mm
022-948 O-RING
044-020 ANVIL
044-021 THREADED RETAINER
044-022 TOOL RECIEVER
044-023 SPRING COMPRESSION
044-024 PISTON, MAGNUM
044-025 HANDPIECE BARREL
044-026 LOCK NUT
044-027 OVAL KNOB
044-028 050-003 CUT TO LENGTH FOR USE
WITH 004-940 HANDPIECE
044-029 4" CUT LENGTH OF 050-002 FOR
MACHINE CONNECTION

LIT-258 PAGE 4 of 4
900 Overlander Road • Emporia, KS 66801 USA
800-835-3519 • 620-343-1084 • Fax: [phone]
[email protected] • www.grstools.com
Last Updated: 2021-04-08
#004-940-ATSS & #004-957SS
Please Note: the Palm Pad mounting screws
should only be lightly snug; over-tightening
can distort or damage the pad.
Magnum® Airtact Palm Knob Kit PARTS LIST #004-957-SS
PART NO. QTY. DESCRIPTION
002-127 2 O-RING, 0.750" O.D. 0.610" I.D.
022-072 1 TUBE COUPLING, 0.170" I.D.
023-024 8 SHCS, #2-56 x 0.19" S/S
023-029 1 FITTING, M-0.063" I.D.TUBE F-LUER
044-026 1 LOCK NUT (MAGNUM)
044-028 1 TUBING, PU CLR 0.250" O.D. 0.160" I.D.
044-029 1 TUBING, PU CLR 0.250" O.D. 0.170" I.D.
044-031 1 HOSE RETAINER
044-110-D1 3 PALM PAD, E2 #04
044-110-E2-06 3 PALM PAD, E2 #06
044-110-E2-08 3 PALM PAD, E2 #08
044-110-E2-10 3 PALM PAD, E2 #10
044-126 1 FITTING, 0.094” O.D.
0.063" I.D. x 0.35"
044-130 1 TUBING, PU CLR 0.125" O.D.
0.063" I.D.
044-162SS 1 PALM KNOB (MAGNUM)
044-204 2 0.500 DIA BLACK SHRINK TUBING
044-219 1 INLET INSERT FOR MAGNUM AT KNOBS
044-231 1 BRAIDED SLEEVE, 0.375" O.D. NYLON
PALM PAD FINE ADJUSTMENT
Type-E Palm Pads
The latest palm pad design for Airtact®hand control is
Type-E, available in four sensitivity levels: 4, 6, 8, and 10.
The handpiece is more responsive (less force required to
activate) with a lower number palm pad installed.
Initially, palm pads can be stiff. This affects the feel and
control. Stiffness may be reduced naturally with a few
hours of use. To reduce stiffness quickly, bend and twist
the control flap to soften. When the preferred softness
is nearly reached, stop and test frequently to adjust until
desired responsiveness is attained. The rubber control
flap can be formed for a custom feel as well.
Forming the Rubber Control Flap
The flexible rubber control flap on the Palm Pad
transforms hand force into handpiece power by
progressively covering a small air vent hole in the upper
rear of the Airtact®handpiece knob.
Forming or bending the control flap one way (concave)
increases the required hand force; bending it the other
way (convex) decreases hand force.
Control Flap
Palm Pad #8
Moderate to heavy
hand force
Palm Pad #10
Most hand force
Palm Pad #4
Least hand force
Palm Pad #6
Light to moderate
hand force
Concave
Convex
To increase required hand force:
Bend the control flap into a more
concave shape. Bending the flap
this direction keeps the flap from
sealing off the Airtact®knob hole
until more hand force is applied.
To decrease required hand force:
Bend the flap into a more convex
shape to decrease the hand force
required. This shape seals the
Airtact®Knob hole with less force
applied.
900 Overlander Road • Emporia, KS 66801 USA
800-835-3519 • 620-343-1084 • Fax: [phone]
[email protected] • www.grstools.com
LIT-365 Last Update: 2019/05/09