medium-sized gas cylinder should be placed on the rear
problems. The only difficulty is in the pulling of the wire for
support. Secure the gas cylinder by fastening chain, with
the whole length of the torch, since aluminium is known to
which it is wound, tightly to the hooks. Do not transport the
have poor mechanical characteristics. The smaller the
welder with large gas cylinders. Remove the cap from the
diameter of the wire the more this problem is accentuated.
cylinder, clean the thread of the connection and open the
This problem can be avoided by making the following
valve for a few seconds to let some of the gas escape. This
changes:
will prevent impurities from entering into the pressure
1.- Replace the guide hose of the torch with a Teflon guide
regulator and damaging it. Check that the connection of the
hose. To withdraw this, simply loosen the screws at the
pressure regulator is fitted with a gasket and tighten it
end of the torch.
securely. Connect the gas hose by tightening the metal hose
2.- Use contact tips for aluminium.
clamp well. Make sure that when the cylinder valve is open,
3.- Replace the wire pulling rollers with those made for
there are no gas leaks. The valve must be kept closed when
aluminium
not using the welder to avoid wasting gas.
4.- Replace the steel guide hose for wire feed with a Teflon
guide hose.
WIRE REEL ATTACHMENT (FIG. D-E )
The above pieces for aluminium welding are available as
- Open the side panel of the generator and remove the
optionals.
locking screw and fit the wire reel onto the spindle so that
the end of the wire is facing upwards. Make sure that none
SPOT WELDING (FIG. G)
of the loops of wire on the reel are overlapping and that
Two overlapping metal sheets can be spot-welded together
the wire unwinds smoothly. Then re-tighten the screw.
using a wire system and weld material.
- Make sure that the towing roller is suited to the wire used.
This model has been specifically designed for the purposes
To replace this, simply remove the locking handwheel.
of spot-welding and is equipped with adjustable timer
- Take the end of the wire and cut it, rounding off the point,
which allows ideal spot-welding time to be set and therefore
and thread it through the two wire guides; the wire should
the creation of spot-welds which have the same
not be bent and should be guided for a few centimetres,
characteristics.
making sure that it runs without implanting itself in the
In order to use the machine for spot-welding, it should be
guide hose of the torch.
set-up as follows:
- Make sure that the groove of the rollers is in line with the
- Replace the nozzle of the torch with the nozzle required
wire guides.
for spot-welding, which is supplied as an accessory. This
- Adjust the lever of the pressure spring in order to provide
nozzle is cylindrical-shaped and has holes for gas
the towing rollers with sufficient pressure. Depending on
escape at the end
the wire used, the lever should be tightened accordingly;
- Turn the current adjustment switch to <maximum>
excessive pressure could twist the wire and make wire
position.
feeding irregular and if there is insufficient pressure, the
- Set the wire feed speed at almost maximum speed.
wire tends to slide on the roller.
- Turn the switch to <TIMER> position
- Adjust the brake with the knob on the spindle in order to
- Set the spot welding time according to the thickness of
reduce the inertia of the wire reel without overloading the
the metal sheets.
towing-motor.
To carry out the spot welding, rest the nozzle of the torch on
- Let the wire run for the whole length of the torch, turn the
the surface of the first metal sheet, then press the torch
main switch to position “
l
” and press the button of the
button in order to start welding: the wire will melt the first
torch. To prevent the wire from implanting itself into the
sheet, pass through this sheet and into the second, making
end of the torch, in the position where the contact tip is
a molten wedge between the two metal sheets.
located, the tip should be removed.
The button should be pressed until the timer interrupts the
welding.
WELDING (FIG. F )
This system allows spot-welding to be carried out which
Once the machine has been prepared for welding by
would not normally be possible with conventional spot-
carrying out the operations described above, simply place
welders, since metal sheets can be joined which do not
the earth clamp in contact with the workpiece and press the
allow access to the rear side such as box-type sheets.
torch button, keeping the torch at a safe distance from the
This system also makes the operator’s work much easier
workpiece.
thanks to the extremely light-weight torch.
Before carrying out difficult sections of welding, tests
The application limits of this system depend on the width of
should be carried out on scrap pieces. These tests should
the first metal sheet; the second sheet may be extremely
be carried out using the adjustment knob in order to obtain
thick.
the best welding possible. If the arc melts in drops and
tends to go out, the speed of the wire should be increased
RIVET WELDING (FIG.H)
or the welding current decreased. If, however, the wire hits
This process allows dented or deformed metal sheets to be
the piece violently and causes material to be projected, the
re-shaped, without having to hammer out the sheets from
wire speed should be reduced.
behind. This is particularly useful for sections of bodywork
It should be remembered that in order to obtain the best
with inaccessible rear sides.
results, each type of wire is suited to a specific current and
The operation is carried out as follows:
wire feed speed. Therefore, for difficult sections of welding
- Replace the nozzle of the torch with the nozzle required
and welding which requires a great deal of time, wires with
for riveting. This nozzle has a side hole for housing the
different diameters should be tried so that the most suitable
rivet.
may be chosen.
- Turn the current adjustment switch to position 3.
- Adjust the feed speed according to the current and the
ALUMINIUM WELDING
diameter of the wire used as if a welding operation was to
For aluminium welding, pure ARGON or an ARGON-
be carried out.
HELIUM mixture should be used for shielding. The wire
- Turn the switch to <TIMER> position.
used should have the same characteristics as the material
- Set the time at 1-1.5 seconds
to be welded. Always use an alloy wire (e.g.
A spot of welding will therefore be carried out at the point
aluminium/silicium); never use pure aluminium wire.
where the head of the rivet is located and so joining the
Aluminium MIG welding does not present any particular
- 9 -
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