Push-Pull Adapter 195 324 For Millermatic® 251
Models Eff w/LE152159
2006−06FORM: OM-220 093B
Use above FORM number when ordering extra manuals.
NOTE
The push-pull adapter enables the Millermatic 251 to be used for aluminum MIG
welding by providing connections for the XR-A Edge gun, XR-A Pistol gun, or
XR-A Python gun.
The push−pull system for aluminum requires installation of U-groove drive rolls in
the Millermatic 251, as well as the correct contact tube, and drive rolls in the
welding gun. These parts are available in the drive roll and accessory kit (order
separately).
1.Safety Symbol Definitions
Warning! Watch Out! There are possible hazards as
shown in the adjoining symbols.
Beware of electric shock from wiring. Turn Off welding
power source and disconnect power before installing this
kit. Reinstall all panels and covers.
Wear safety glasses with side shields.Cylinders contain gas under high pressure and can ex-
Drive rolls can injure − keep away from pinch points and
moving parts on wire feeder.
Have only trained and qualified persons install, operate,
or service this unit. Call your distributor if you do not understand the directions. For WELDING SAFETY and
EMF information, read welding power source Owner’s
Manual.
Hot parts can cause burns. Welding makes parts very hot
− let them cool before touching.
plode if damaged. Never let a welding electrode touch
any cylinder. Always secure cylinder to running gear, wall,
or other stationary support.
Welding wire can cause puncture wounds. Do not point
gun toward any part of the body or at other people when
threading welding wire, or anytime when running out wire
and not welding.
2.Specifications
Specification
Input Power24 Volts AC (Provided By Millermatic 251 )
Control Circuit Voltage Provided to Gun24 Volts DC
Welding Power Source TypeMillermatic 251 Eff w/LE152159
4.Preparing Millermatic 251 And Gun For Push-Pull Adapter Kit Installation
NOTE
Make the changes listed in Sections A and B below prior to installing the push-pull
adapter.
A. Changing Millermatic 251 Drive Roll
1 Drive Roll
Install U-groove drive rolls in the
2
1
Top View
1
2
Millermatic 251 to match wire
diameter. Drive rolls are included in
drive roll and accessory kit.
2 Drive Roll Securing Nut
Turn nut one click to secure drive
roll.
B. Changing XR-A Gun Drive Rolls
1
XR-A Edge Gun
2
Ref. 802 990 / Ref. 802 064-D / Ref. 800 412-A
1 Barrel Assembly
2 Nut
3 Capscrew
3
1
XR-A Pistol
XR-A Edge Gun: Loosen nut and
remove gun barrel assembly.
XR-A Pistol: Remove two
capscrews beneath cover to
remove barrel.
Install correct drive rolls in gun to
match wire diameter (see gun
Owner’s Manual). Drive rolls and
other required parts are included in
drive roll and accessory kit.
on lower right side of Millermatic 251 as
shown. Align adapter slots with mounting
holes and reinstall screws.
2
Notes
3
803 462
Work like a Pro!
Pros weld and cut
safely. Read the
safety rules at
the beginning
of this manual.
OM-220 093 Page 3
Page 4
6.Connecting Push-Pull Adapter
10
1
2
.An XR-A Edge gun is shown in these
instructions.
Make connections as shown:
1 Millermatic 251
Install U-groove drive rolls in Millermatic 251
to match wire diameter. See Section 4 for
U-groove drive roll installation information.
Drive rolls are included in drive roll and
accessory kit.
2 XR-A Edge Gun
Connect gun and weld
cable as shown in
Sections 7 and 8.
3
6
4
8
.See gun Owner’s Manual for information
on installing gun components.
Install correct liner and drive rolls in gun to
match wire diameter (see Section 4). Drive
rolls, liner, and other required parts are
included in drive roll and accessory kit.
Open pressure assembly.Pull and hold wire; cut off end.
621
.Set pressure indicator to
.Hold wire tightly to keep it
from unraveling.
6 in
(150 mm)
1 for aluminum wire.
Tighten
1
2
3
4
Pressure
Indicator
Scale
Push wire thru guides into gun;
continue to hold wire.
Set Adapter Run-In speed to 40%.
Close and tighten pressure
assembly, and let go of wire.
Thread wire through gun
(see Section 11).
803 463 / S-0627-A
OM-220 093 Page 7
Page 8
11.Threading Welding Wire Through XR-A Gun
For XR-A Edge Gun:
1
Turn On
Millermatic
251.
Remove barrel assembly before
threading wire through gun.
Y Welding wire is electrically live
when gun trigger is used to jog
wire.
.Refer to Section 10 for instructions on
feeding wire through Millermatic 251.
1 Pressure Roll Assembly
Lay gun cable out straight.
Open top cover, and open pressure roll as-
sembly. If not already done, remove gun
barrel assembly.
Press gun trigger until about 4 in (102 mm)
of wire is sticking out front of gun. Insert
wire into barrel liner and tighten barrel assembly. Install correct size contact tube
and install collet nut.
Close top cover on gun. Press trigger
switch until about 6 in (152 mm) of wire is
sticking out end of contact tip. See final
pressure adjustment at bottom of page.
For XR-A Pistol Gun:
Turn On
Millermatic
251.
For Both Guns:
.Procedure is the same for
pistol-grip gun.
1
Remove barrel assembly
before threading wire
through gun.
1 Pressure Roll Assembly
2
3
2 Drive Roll
3 Thumbscrew
Lay gun cable out straight. Open top
cover, and lift pressure arm and open
pressure roll assembly. If not already
done, remove gun barrel assembly.
Manually thread wire along drive roll
groove. Close pressure roll assembly.
Press gun trigger until about 4 in (102 mm)
of wire is sticking out front of gun. Insert
wire into barrel liner and tighten barrel assembly. Install correct size contact tube
and install collet nut. Reinstall gun cover.
4 Pressure Adjustment Knob
See final pressure adjustment at bottom of
page.
Tools Needed:
OM-220 093 Page 8
Nonconductive
Surface
Feed wire to check drive roll
pressure. If necessary, slightly
tighten thumb nut inside gun.
.Do not exceed midrange setting.
Cut off wire. Close and latch wire
feeder door.
Y Turn Millermatic 251 Off.
Ref. 802 193-A / 801 556
Page 9
12. Setting Push-Pull Adapter And XR-A Gun Controls
2
3
2
3
1
1 Adapter Run-In Speed Control
Use control to set run-in wire feed speed
before arc initiation.
After arc initiation, weld wire feed speed is
controlled by the wire speed setting on the
welding gun.
The scale around the run-in speed control
is a percent of weld wire feed speed.
If using .047 wire, set control to 10% for best
results. If using .040 wire, set control to 25%
for best results. If using .035 wire, set control to 40% for best results.
.The gun wire feed speed control adjusts
wire speed from minimum to maximum
setting as displayed on Millermatic 251.
803 432 / 151 666
2 Trigger
Press trigger to energize Millermatic 251,
weld output, start shielding gas flow, and
begin wire feed.
3 Wire Speed Control
Use control to adjust wire feed speed. The
numbers around the control are for
reference only.