WIDMANN MIG/TIG/MMA-160 Manuel Utilisateur page 8

4. Straighten the wire end for approximately 20 cm and cut the wire in the
straightened location.
5. Open the pressure control lever which then opens the feed gear.
6. Thread the wire through the wire's rear guide to the gun's wire guide.
7. Close the feed gear and fasten it with the pressure control lever. Make sure that the
wire runs in the feed roll groove.
8. Adjust the compression pressure with the pressure control lever no higher than to
the middle of the scale .lf the pressure is too high, it removes metal fragments from
the wire surface and may damage the wire. On the other hand, if the pressure is too
low, the feed gear slips and the wire does not run smoothly.
9. Press the welding gun trigger and wait for the wire to come out.
10. Close the reel housing cover.
CAUTION! When driving the wire in to the gun, do not point the gun at yourself
or others or put, for example, your hand in front of the tip, because the cut wire
end is extremely sharp. Also, do not put your fingers near the feed rolls, because
they might get squeezed between the rolls.
3.4.3 Reversing polarity
Some filler wires are recommended to be welded with the gun in the - pole. So the
polarity should be reversed. Check the recommended polarity from the filler wire
package.
1. Disconnect the machine from the mains.
2. Bend the rubber cover of the earth cable's pole in such way that the cable can be
disconnected.
3. Remove poles tightening nuts and washers. Note the correct order of the washers!
4. Interchange the cables.
5. Install the washers in place and close the tightening nuts to spanner tightness.
6. Put the rubber cover of the earth cable's pole firmly in place. The rubber cover
must always protect the earth cable's pole.
Welding power adjustment
Adjusting the welding power according to sheet thickness affects simultaneously
both wire feed speed and amount of current lead to the wire. This is a good starting
point for welding in different operating situations. However, connection type and root
opening may influence the amount of welding power needed.
Select the correct parameter with the welding power control according to the welded
fillet weld's sheet thickness. If the fillet weld's sheets are of different thickness, use
their average as a default parameter.
Sheet thickness scale has been given in millimeters and it is based on 0.8 mm wire
diameter. When using a 0.6 mm wire, set the welding power control slightly higher
than the used sheet thickness and correspondingly slightly lower with 0.9-1.0 mm
wires.
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