1. Gas Metal Arc Welding (GMAW)
Parts Identification

2. Miller Shopmaster 300 AC/DC
There are several fine brands of welding machines and while they may be used for the same welding process, the switches and controls may be located in different places and may have different functions.
Several parts and controls of various welding equipment may be correctly referred to by different names. For the purposes of this course we will refer to them as they are depicted in this presentation.
We will not be covering “all” of the parts of the GMAW equipment in this course, however a few more will need to be introduced during the setup/maintainance and adjustment portion of the course.

3. Power Source Power Switch Process Switch Voltage Arc Control
Output Contactor
Remote Amps/Volts

4. Work Lead
Disconnect
Work Clamp

5. Wire Feeder

6. Wire Feeder (older style)
Jog Button
Power Switch
Purge Button
Wire Feed Speed

7. Wire Feeder (newer style)
Wire Feed Speed
Power Switch is on the back
Purge and Jog Switch
Trigger Hold

8. Mig Gun
Pin Connector

9. Mig Gun Parts
Nozzle
Contact Tip
Insulator
Gas Difuser

10. Inside the Wire Feeder Tension Knob Drive Rolls .035 or .045
Wire Cleaner
Positive DC Power

11. Inside the Wire Feeder
Guide Tube
Thumb Screw
Set Screw

12. Shielding Gases Open All the Way Cylinder Pressure Float Ball
Adjusting Knob
Read the Label
75% Argon – 25% CO2

13. Mig Wire