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Pouring can be completely turned off
and on by pressing the red and green
vertical switch.
The mold temperature can also be
adjusted here. Note that entering a
mold temperature of 20°C switches to
“solution” mode.
If pouring is on, the crucible tilting
angle and speed can be controlled with
the plus and minus buttons.
Generally, a pouring angle of 120° with a speed of more than 30% works well.
Adjustment is sometimes required to adapt to melt viscosity and mold size.
Cooling steps
The cooling process is normally divided into two distinct steps. The first cooling
stage (Cooling 1) is a natural-convention cooling, that is, without any forced-air
cooling. This allows for the melt to completely fill the molds while the molds are as
hot as possible, and is of key importance in the stabilizing of the melt.
Indeed, in most cases, if we were to start the forced air circulation immediately
after pouring, the bead would not cool down uniformly, and residual thermal
stresses would remain in the solid disk. This can cause hazardous bursting of the
produced disk, in the next minutes, hours or even days.
On the other hand (and again there are exceptions) if the blowers were to start
too late (Cooling 2), a crystallization reaction could occur if the molecules have
enough time to arrange in an orderly fashion. Crystallization reactions cause the
transparent melt to become milky-opaque, typically from the edges towards the
center of the mold, pushing the still-liquid melt to the center and upwards as
crystallization progresses, thus creating a volcano-like structure. Therefore the
solution resides in finding the correct time for still-air cooling (Cooling 1), and then
the blower can start and work until the molds are comfortably cool to the touch.
Duration
Step duration (mm : ss) is adjusted by pressing on the plus and minus buttons.
Generally speaking, a “Cooling 1” duration of one to two minutes is a very good
starting point. Thereafter, “Cooling 2” can be set for as many minutes as needed,
and this parameter will be roughly proportional with the melt and mold combined
weight.
Crucible position after pouring
Summary of Contents for K1 PRIME
Page 1: ...Automatic fluxer 1...
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