Tweco FP-165 Mini MIG - Manual (Page 46)

FIREpOwER Fp-125, 135, 165 SERVICE
Manual 0-5123 5-2 Service
2. Inconsistent wire feed
Wire feeding problems can be reduced by checking the
following points:
1. Wire spool brake is too tight.
a. Feed roller driven by motor in the cabinet will
slip.
2. Wire spool brake is too loose.
a. Wire spool can unwind and tangle.
3. Worn or incorrect feed roller size.
a. Use ‘U’ groove drive feed roller matched to
the aluminum wire size you are welding. Use
‘V’ groove drive feed roller matched to the
steel wire size you are welding. Use ‘knurled
V’ groove drive feed roller matched to the flux
cored wire size you are welding.
4. Misalignment of inlet/outlet guides.
a. Wire will rub against the misaligned guides and
reduces wire feedability.
5. Liner blocked with slag.
a. Slag is produced by the wire passing through
the feed roller, if excessive pressure is applied
to the pressure roller adjuster. Slag can also
be produced by the wire passing through an
incorrect feed roller groove shape or size. Slag
is fed into the liner where it accumulates, thus
reducing wire feedability.
6. Incorrect or worn contact tip.
a. The contact tip transfers the weld current to
the electrode wire. If the hole in the contact
tip is too large, then arcing may occur inside
the contact tip resulting in the electrode wire
jamming in there. When using soft electrode
wire such as aluminum, the wire may become
jammed in the contact tip due to expansion of
the wire when heated. A contact tip designed
for soft electrode wires should be used.
7. Poor work lead contact to work piece.
a. If the work lead has a poor electrical contact to
the work piece, then the connection point will
heat up and result in a reduction of power at
the arc.
8. Bent liner.
a. This will cause friction between the wire and
the liner thus reducing wire feedability