WELDTECH WT200MP, Operating Instructions Manual

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end of the MIG torch. Replace the tip on the MIG
torch and trim off any excess wire.
3. Gasless Welding Operation
3.1 Connect the earth cable quick connector to the
positive welding power output socket (12). Con-
nect the earth clamp to the work piece. Contact
with the work piece must be firm contact with
clean, bare metal, with no corrosion, paint or scale
at the contact point.
3.2 Connect the MIG power connection lead (14) to
the negative welding power output socket (13).
Note if this connection is not made, there will be
no electrical connection to the welding torch!
3.3 Set the welding voltage adjustment knob (8), wire
speed control knob (9) and inductance control
knob (10) to the desired positions. You are now
ready to weld!
4. Gas MIG Welding Operation
NOTE
: Gas MIG welding will require a gas cylinder. (Argon
mix or CO2)
4.1 Connect the earth cable quick connector to the
negative welding power output socket (13). Con-
nect the earth clamp to the work piece. Contact
with the work piece must be firm contact with
clean, bare metal, with no corrosion, paint or scale
at the contact point.
4.2 Connect the MIG power connection lead (14) to
the positive welding power output socket (12).
Note if this connection is not made, there will be
no electrical connection to the welding torch!
4.3 Connect the gas regulator to a gas cylinder (not
included with machine) and connect the gas hose
from the regulator to the gas inlet on the rear of
the machine (15). Ensure all hose connections are
tight. Open gas cylinder valve and adjust regulator,
flow should be between 10-25 L/min depending
on application. Re-check regulator flow pressure
with torch triggered as static gas flow setting may
drop once gas is flowing.
4.4 Set the welding voltage adjustment knob (8), wire
speed control knob (9) and inductance control
knob (10) to the desired positions. You are now
ready to weld!
MIG welding with aluminium provides a unique
challenge, due to the low column strength and
surface friction of the wire. This causes the wire
to deform more as it is pushed through the feed
mechanism and the torch wire delivery liner, great-
ly increasing friction. Because good MIG welding
results are dependent on a smooth wire feed, cer-
tain changes must be made to the wire feed sys-
tem to minimise friction caused issues.
For a standard ‘push’ fed torch, a length of no long-
er than 3m cable should be used, as well as the
torch feed liner must be changed to a special Tef-
lon/ PVC liner, rather than the conventional steel
liner. Also the correct style drive roller must be
used and specific Aluminium rated torch contact
tip (or a standard tip in one size oversize, e.g 0.8mm
aluminium wire, use standard 1.0mm contact tip).
For this reason, it is quite common for operators
to have an extra MIG torch specifically set up for
aluminium use, if the machine is used for weld-
ing steel as well. Another option to overcome the
friction issues is using a spool gun, which will give
better results than a 3m push torch when welding
aluminium. The WT200MP is spool gun capable,
refer following section for use with a spool gun on
the WT200MP.
5. Spool Gun Operation
NOTE:
Spool Gun is an optional extra for the WT200MP.
Spool gun part number: 13323
The spool gun is a very useful addition to a MIG welder.
It can be used for all types of MIG welding, but it has
two primary advantages over a conventional ‘push’ wire
feeder. The main advantage is that distance that the
wire has to travel from the spool to the welding tip is
very short, compared with a conventional torch. This
greatly reduces the wire feeding friction and improves
the wire feed speed smoothness and consistency, thus
the welding quality is greatly improved. This is especial-
ly so with ‘soft’ wires such as Aluminium. It is difficult to
get Aluminium to feed smoothly in welding machines
equipped with standard design wire feeders, even with
special torch liners and short torch lengths.
The second advantage is that the gun can allow the
use of the small D100 wire spools at a distance from
the power source (This distance is only limited by the
length of the spool gun lead). This is advantageous for
high cost wire, that is not used commonly such as Stain-
less Steel or MIG brazing wire. It saves the outlay cost for
a much more expensive, larger D200 spool.
5.1 Connect the earth cable quick connector to the
negative welding power output socket (13). Con-