Kemppi MF 33 - Manual (Page 10)

EN
3.2 Mounting of MIG welding gun
In order to ensure trouble-free welding check in operation instructions of gun used by you
that wire guide tube and contact tip of gun are according to manufacturer’s recommendation
suitable to be used for wire feed diameter and type in question. To tight a wire guide tube
might cause for wire feed unit a bigger stress than normally as well as disturbances in wire
feed.
Screw snap connector of gun tight that there won’t come any voltage losses on connecting
surface. A loose connection will heat gun and wire feed unit and feeder.
3.3 Mounting and locking of wire spool
LOCKED OPEN
• Release locking nails of wire spool hub by turning locking knob a quarter round.
• Mount the spool at its place. Note rotating direction of spool!
• Lock the spool with locking knob, locking nails of hub remain to outside position and
will lock the spool.
NOTE! Check that in filler wire spool there are no parts sticking out, which could e.g. chafe against
chassis or door of wire feed unit. Dragging parts might expose chassis of wire feed unit under
voltage.
3.4 Automatic wire feed to gun
Automatic wire feed makes change of wire spool more rapid. In spool change the pressure of
feed rolls need not to be released and filler wire goes automatically to correct wire line.
• Make sure that groove of feed roll matches the diameter of welding wire used.
• Release the wire end from spool and cut off the bent length. Be careful that the wire
does not spill from the spool to sides!
• Straighten about 20 cm of the wire and see that the end of it has no sharp edges (file
off if necessary). A sharp edge may damage the wire guide tube and contact tip of the
welding gun.
FastMig MF wire feed units:
• Draw a bit of loose wire from wire spool. Feed wire through back liner to feed rolls. Do
not release pressure of feed rolls!
• Press the gun switch and feed a bit wire until wire goes through feed rolls to gun. See
that wire is in grooves of both feed roll pairs!
• Press still the gun switch until wire has come through contact tip.
Automatic feed may sometimes fail with thin wires (Fe, Fc, Ss: 0,6 – 0,8 mm, Al: 0,8 – 1,0 mm).
In that case you might have to open feed rolls and feed wire manually through feed rolls.
3.5 Adjustment of pressure
Adjust the pressure of feed rolls with the control screw so that the wire is fed into the wire
guide tube evenly and allows a little braking when coming out from the contact tip without
slipping at the feed rolls.
NOTE! Excessive pressure causes flattening of the filler wire and damage to the coating. It also
causes undue wear of the feed rolls as well as friction.
FastMig MF 33
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