Lincoln Electric IM794 manual Friction Brake Adjustments, Wire Threading

B-4 OPERATION B-4

Note: The brake should be adjusted with a spool of wire installed. When properly adjusted it should move freely but not coast.

Friction Brake Adjustments

1.With wire spool installed, check free movement and coast of the spool.

2.To tighten the brake turn the wing nut clockwise in 1/4 turn increments until coasting stops.

3.To loosen the brake turn the wing nut counter- clockwise in 1/4 turn increments until the wire spool moves freely without coasting.

Wire Threading

Refer to Figure B.4

1.Release the Spring Loaded Pressure Arm (1) rotate the Idle Roll Arm (2) away from the Wire Feed Drive Roll (3). Ensure that the groove size in the feeding position on the drive roll matches the wire size being used. See Maintenance section for further information.

2.Carefully detach the end of the wire from the spool. To prevent the spool from unwinding, main- tain tension on the wire until after step 5.

3.Cut the bent portion of wire off and straighten the first 4” (100 mm).

4.Thread the wire through the ingoing guide tube (4), over the drive roll (3), and into the outgoing guide tube (5).

5.Close the idle roll arm and latch the spring loaded pressure arm (2) in place. Rotate the spool coun- terclockwise if required to take up extra slack in the wire.

6.The idle roll pressure adjustment wing nut is nor- mally set for mid-position on the pressure arm threads. If feeding problems occur because the wire is flattened excessively, turn the pressure adjustment counter-clockwise to reduce distortion of the wire. Slightly less pressure may be required when using 0.023 – 0.025” (0,6 mm) wire. If the

6.drive roll slips while feeding wire, the pressure should be increased until the wire feeds properly.

7.Refer to Figure B.5. Remove gas nozzle and con- tact tip from end of gun.

FIGURE B.4

2

	Wire from spool.
	1
	4
3	The Wire Drive Feed Roll
5	can accommodate two wire

sizes by flipping the wire drive feed roll over.

WARNING

When inching the welding wire, the drive rolls, the gun connector block and the gun contact tip are electrically energized relative to work and ground and remain energized for several seconds after the gun trigger is released.

8.Turn the SP-170T ON (“I”).

9.Straighten the gun cable assembly.

10.Depress the gun trigger switch and feed welding wire through the gun and cable. (Point gun away from yourself and others while feeding wire.) Release gun trigger after wire appears at end of gun.

11.Turn the SP-170T OFF (“O”).

12.Replace contact tip and gas nozzle.

FIGURE B.5

Gun Handle

Gas Diffuser/

Contact Tip

Gas Nozzle

13.Refer to Figure B-6. Cut the wire off 3/8” – 1/2” (10

– 13 mm) from the end of the tip. The SP-170T is

now ready to weld.

SP-170T