Wire Reel Brake; Gas Regulator Operation - Firepower MST 180i Operating Manual

Firepower MST 180i

3.18 Wire Reel Brake

The wire reel hub incorporates a friction brake which is adjusted during manufacture for optimum breaking. If it is considered
necessary, adjustment can be made by turning the large nut inside the open end of the hub clockwise to tighten the brake.
Correct adjustment will result in the wire reel circumference continuing no further than 3/8" (10mm) - 3/4" (20mm) after
release of the trigger. The electrode wire should be slack without becoming dislodged from wire spool.
Overtension of brake will cause rapid wear of mechanical WIREFEED parts, overheating of electrical components
and possibly an increased incidence of electrode wire Burnback into contact tip.

3.19 Gas Regulator Operation

With the regulator connected to cylinder or pipeline, and the adjustment screw/knob fully disengaged, pressurize as follows:
1. Stand to one side of regulator and slowly open the cylinder valve. If opened quickly, a sudden pressure surge may
damage internal regulator parts.
2. With valves on downstream equipment closed, adjust regulator to approximate working pressure. It is recommended
that testing for leaks at the regulator connection points be carried out using a suitable leak detection solution or
soapy water.
3. Purge air or other unwanted welding grade shielding gas from equipment connected to the regulator by individually
opening then closing the equipment control valves. Complete purging may take up to ten seconds or more, depending
upon the length and size of the hose being purged.
Adjusting Flow Rate
With the regulator ready for operation, adjust working flow rate as follows:
1. Adjust the gas flow rate. The recommended rate for MIG welding is 28-46 CFH. The recommended rate for LIFT TIG
welding is 10-28 CFH.
It may be necessary to re-check the shielding gas regulator flow rate following the first weld sequence due to
back pressure present within shielding gas hose assembly.
Shutdown
Close cylinder valve whenever the regulator is not in use. To shut down for extended periods (more than 30 minutes).
1. Close cylinder or upstream valve tightly.
2. Open downstream equipment valves to drain the lines. Bleed gas into a well ventilated area and away from any ignition
source.
3. After gas is drained completely, disengage adjusting screw and close downstream equipment valves.
4. Before transporting cylinders that are not secured on a cart designed for such purposes, remove regulators.
INSTALLATION, OPERATION AND SETUP
Wire Reel Brake Adjustment Nut
Figure 3-15: Wire Reel Brake
3-18
CAUTION
Art #
A-12446
NOTE
Manual 0-5339