Tack
Welding
Welding
operations are completed in two stages. First, tack weld
the base of the crack. The heat knits the sides of the
crack together and holds both sections of the component
in alignment.
 Tack
welding nozzle 28 (push fitted onto the standard nozzle
of the LEISTER TRIAC) is used at the temperature
specified for the material (see table). The weld is best
completed in one continuous run from end to end, drawing
the welding nozzle tip along the base of each 'V' groove.
The sole of the nozzle should be inclined at an angle not exceeding 20° to the groove base. As the nozzle is drawn along, hot air softens the plastic below the heel of the nozzle and the toe draws the softened material together.
 Avoid
applying pressure to the weld via the tool, as the material
at the base of the groove is thin and not strong. While tack welding, minor misalignment of the panel sides or newly inserted material can be corrected by holding the sections in position until the weld has knitted and cooled.
After each welding
run, brush the nozzle clean with a brass suede brush. Remove
any difficult residue by increasing the heat level to maximum
to soften it.
|
