Lincoln Electric IM742-A manual Wire WELDING-CV, Typical Current Ranges 1 for Tungsten ELECTRODES2

B-5 OPERATION B-5

TIG Welding

The TOUCH START TIG setting of the MODE switch is for DC TIG (Tungsten Inert Gas) welding. To initiate a weld, the CONTROL dial is first set to the desired cur- rent and the tungsten is touched to the work. During the time the tungsten is touching the work there is very little voltage or current and in general, no tungsten con- tamination. Then, the tungsten is gently lifted off the work in a rocking motion, which establishes the arc.

The ARC CONTROL is not active in the TIG mode.To STOP a weld, simply pull the TIG torch away from the work. When the arc voltage reaches approximately 30 Volts the arc will go out and the machine will reset the current to the Touch Start level. To reinitiate the arc, re touch the tungsten to the work and lift. Alternatively, the weld can be stopped by releasing the Amptrol or arc start switch.

The Ranger 305G can be used in a wide variety of DC TIG welding applications. In general the ‘Touch Start’ feature allows contamination free starting without the use of a Hi-frequency unit. If desired, the K930-2 TIG Module can be used with the Ranger 305D. The set- tings are for reference.

Ranger 305G settings when using the K930-2 TIG Module with an Amptrol or Arc Start Switch:

•Set the MODE Switch to the TOUCH START TIG setting.

•Set the "IDLER" Switch to the "AUTO" position.

•Set the "WELDING TERMINALS" switch to the "REMOTELY CONTROLLED" position. This will keep the "Solid State" contactor open and provide a “cold” electrode until the Amptrol or Arc Start Switch is pressed

When using the TIG Module, the OUTPUT control on the Ranger 305G is used to set the maximum range of the CURRENT CONTROL on the TIG module or an Amptrol if connected to the TIG Module.

WIRE WELDING-CV

Connect a wire feeder to the RANGER 305G accord- ing to the instructions in INSTALLATION INSTRUC- TIONS Section.

The RANGER 305G in the CV-WIRE mode, permits it to be used with a broad range of flux cored wire (Innershield and Outershield) electrodes and solid wires for MIG welding (gas metal arc welding). Welding can be finely tuned using the ARC CON- TROL. Turning the ARC CONTROL clockwise from –10 (soft) to +10 (crisp) changes the arc from soft and washed-in to crisp and narrow. It acts as an induc- tance control. The proper setting depends on the pro- cedure and operator preference. Start with the dial set at 0.

Some recommended Innershield electrodes are: NR-311, NS-3M, NR-207, NR-203 Ni 1%, NR-204-H.

Recommended Outershield electrodes are: 0S-70, 0S-71M.

Some recommended solid wires for MIG welding are:

.035 (0.9 mm), and .045 (1.1 mm), L-50 and L-56, .035 (0.9 mm) and .045 (1.1 mm) Blue Max MIG 308 LS. For any electrodes, including the above recommenda- tions, the procedures should be kept within the rating of the machine.

TYPICAL CURRENT RANGES (1) FOR TUNGSTEN ELECTRODES(2)

Tungsten Electrode		DCEN (-)	DCEP (+)		Approximate Argon Gas Flow					TIG TORCH
Diameter in. (mm)					Flow Rate C.F.H. ( l		/min.)			Nozzle Size (4), (5)
		1%, 2% Thoriated	1%, 2% Thoriated		Aluminum			Stainless Steel
		Tungsten	Tungsten
.010	(.25)	2-15	(3)		3-8	(2-4)		3-8	(2-4)	#4, #5, #6
0.020	(.50)	5-20	(3)		5-10	(3-5)		5-10	(3-5)
0.040	(1.0)	15-80	(3)		5-10	(3-5)		5-10	(3-5)
1/16	(1.6)	70-150	10-20	1	5-10	(3-5)		9-13	(4-6)	#5, #6
3/32	(2.4)	150-250	15-30	1	13-17	(6-8)		11-15	(5-7)	#6, #7, #8
1/8	(3.2)	250-400	25-40		15-23	(7-11)		11-15	(5-7)
5/32	(4.0)	400-500	40-55		21-25	(10-12)		13-17	(6-8)	#8, #10
3/16	(4.8)	500-750	55-80		23-27	(11-13)		18-22	(8-10)
1/4	(6.4)	750-1000	80-125		28-32	(13-15)		23-27	(11-13)

(1)When used with argon gas. The current ranges shown must be reduced when using argon/helium or pure helium shielding gases.

(2)Tungsten electrodes are classified as follows by the American Welding Society (AWS):

Pure	EWP
1% Thoriated	EWTh-1
2% Thoriated	EWTh-2

Though not yet recognized by the AWS, Ceriated Tungsten is now widely accepted as a substitute for 2% Thoriated Tungsten in AC and DC applications.

(3)DCEP is not commonly used in these sizes.

(4)TIG torch nozzle "sizes" are in multiples of 1/16ths of an inch:

# 4 = 1/4 in.		(6 mm)
# 5	= 5/16 in.	(8 mm)
# 6	= 3/8 in.	(10 mm)
# 7	= 7/16 in.	(11 mm)
# 8	= _ in.	(12.5 mm)
#10 = 5/8 in.		(16 mm)

(5)TIG torch nozzles are typically made from alumina ceramic. Special applications may require lava nozzles, which are less prone to breakage, but cannot withstand high temperatures and high duty cycles.

RANGER 305G