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NS20A & NS20N Heavy Duty Gun
Page 2
Revision 1.20 2/19/08
GUN SETUP FOR WELDING STEEL STUDS
Accessory Installation
1. Insert chuck for 1” or smaller studs into the
chuck adaptor. While holding the gun by the
chuck adapter, lightly tap the chuck with a
hammer until it is seated and held firmly in the
taper of the chuck adapter (
Figure 1
). Chucks
for studs larger than 1” diameter screw onto the
½-20 thread of the hex shaft adapter.
Note:
A different Chuck is required for each
stud diameter.
2. Insert Ferrule Grip into Foot and secure with
setscrews provided (
Figure 1
).
3. Insert stud in Chuck and Ferrule in Ferrule Grip
or Ferrule Holder.
4. Loosen the screws holding the foot to the leg
and adjust the foot so that stud is centered in
the ferrule.
This is important
because improper
welds will result if there is binding or friction
between the stud and ferrule. Tighten the
screws and recheck the centering.
Hex Shaft
Adaptor
Chuck
Adaptor
Chuck
Foot
Ferrule
Grip
Leg
Setscrews
Leg
Plunge
1/8" - 1/4"
Figure 1: Gun assembly
Plunge Adjustment
1. Adjust the leg and foot assembly so that the
stud extends ⅛” to ¼” beyond the end of the
ferrule (
Figure 1
).
2. When plunge is adjusted, tighten the leg screws
so that the Foot Assembly cannot move.
Note:
It is necessary to adjust plunge when
changing stud lengths.
Free Travel Adjustment
With the free travel adjustment sleeve screwed
fully in, (clockwise) there will be 1/16” of free
travel. To increase the free travel, back out
(counter-clockwise) the free travel adjustment
sleeve. Each complete full turn provides .071” of
additional free travel (
Figure 2
).
Free travel adjusting sleeve
(plunge dampener)
Front of gun has been removed for clarity
Figure 2: Location of free travel sleeve
Note:
A 1/2” open-end wrench is the proper tool
for adjusting the free travel.
For studs with a weld base of ½”
diameter or under:
1/8 turn
For studs with a weld base of 5/8”
to ¾” diameter:
½ - ¾ turns
Larger diameter studs can tolerate increased free
travel.
These recommendations are for normal stud
welding applications. For special applications such
as Weld-Thru Deck, obtain appropriate application
sheet.