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8. CONTROLS
8.1.
CONTROLS - SUPERMIG 255
functions are identical for both models.
8.2.
SYSTEM PROTECTION
A thermostat is built into the system to protect against overheating. The indicator light comes on when overheating occurs and cuts off the
power supply. It will reset automatically within a few minutes, after cooling down.
9. WELDING PRINCIPLES
Should you have no welding experience, we recommend you seek training from an expert source to ensure your personal health & safety.
You must familiarise yourself with welding applications and limitations, and specific potential hazards peculiar to welding.
Good Mig welding may be achieved only with continued, supervised practice.
9.1.
MIG/MAG WELDING. (See fig.17). A reel of welding wire is placed
on the reel holder and automatically fed through an insulated liner in
the torch to its tip. The torch consist of a switch, liner, gas hose, and
control cable. The switch activates the wire feed roller and the gas
flow. Releasing the switch stops wire feed and gas flow. The weld
current is transferred to the electrode (the wire) from the contact tip
at the torch end.
Wire speed must be adjusted according to power output. The higher
the current the faster the wire speed. A gas cup fits over the contact
tip to direct gas flow towards the weld ensuring the arc welding
process is shielded from oxidising air contamination (fig.19). The shielding gas also assists heating of the weld. The torch is connected to
the positive side of a DC rectifier, and negative clamp is attached to the workpiece.
9.2.
PREPARATION FOR WELDING.
IMPORTANT: BEFORE YOU COMMENCE, MAKE SURE THE MACHINE IS SWITCHED OFF AT THE MAINS. IF WELDING A
VEHICLE, DISCONNECT THE BATTERY OR FIT AN ELECTRONIC CIRCUIT PROTECTOR. ENSURE YOU READ AND
UNDERSTAND THE SAFETY INSTRUCTIONS IN CHAPTER 1.
9.2.1.
Connecting the Earth Lead.
Connect the earth lead as described in section 6.4.
To ensure a complete circuit, the earth lead clamp must be securely attached to the workpiece that is to be welded.
a) Best connection is obtained by grinding the point of contact on the workpiece before connecting clamp to the workpiece.
b) The weld area must also be free of paint, rust, grease, etc.
c) If welding a vehicle, disconnect vehicle battery or fit an "Electronic Circuit Protector" to battery, (available from your Sealey stockist).
9.2.2.
The wire feed rate rotary controls are used to set the speed of the wire feed. In principle, the lower the amperage number the slower the
wire speed.
9.3.
GAS TYPES AND THEIR USE.
Welding mild steel with CO ² gas is appropriate for most welding tasks where spatter and high build up of weld do not pose a problem.
To achieve a spatter free and flat weld however, as a guideline, use an Argon/CO ² mixture. To weld aluminium use: Argon gas or
Argon-Helium mixture, 0.8mm Contact Tip, 0.8mm Aluminium Wire, (MIG/2/KAL08) Liner (red) Aluminium
10. COMMENCING WELDING
10.1.
COMMENCING WELDING.
10.1.1.
Ensure that the welding mode switch is set to the 'CONTINUITY' welding position.
10.1.2.
Before carrying out difficult sections of welding, tests should be carried out on scrap pieces of metal. These tests should be carried
out to find the best control settings in order to obtain the best welding result. As a starting point refer to the welding guide below. If the
arc melts in drops and tends to go out, the speed of the wire should be increased or the welding current decreased. If, however, the wire
hits the piece violently and causes material to be projected, the wire speed should be reduced.
10.1.3.
It should be remembered that in order to obtain the best results, each type of wire is suited to a specific current and wire feed speed.
Therefore, for difficult sections of welding and welding which requires a great deal of time, wires with different diameters should be tried
so that the most suitable may be chosen.
© Jack Sealey Limited
Fig.16 illustrates the main panel controls for both Supermig255 & Supermig275. The control
IMPORTANT.
Original Language Version
fig.16
.
SUPERMIG255.V2
fig.17
Issue:1 - 11/07/22
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