Sutter Instrument P-97, Operation Manuals

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that produced the shorter pipette. Then tighten up the clamps and try another pull. You may
have to go through several iterations before you get it centered properly.
Line pipettes up at
their shoulders and
compare their
len
Right-side pipette is longer than the one on the
left. Shift heating filament to the left
gths.
a small
amount (move filament towards shortest pipette).
Figure 4-3. Micropipette shapes.
4.3 Pulley Adjustment
NOTE: Contacting Sutter Instrument Technical Support is highly recommended before
performing a pulley adjustment.
The position of the two pulleys (F in Figure 4-4A) which guide the cables from the solenoid
(not shown) to the puller bars (G in Figure 4-4A) is adjustable. The pulley position controls
the tension of the cables. A difference between the tensions of the two cables can cause
problems with pipette reproducibility and/or a disparity between the taper lengths of the pair
of pulled pipettes (as illustrated in Figure 4-4). Taper length inequality is generally caused by
the air jet not being aimed at the center of the filament, so to avoid unnecessary adjustments
to the pulleys, be certain that the filament and air jet are correctly positioned before
proceeding.
The pulley adjustment is made by moving one or both of the pulleys to equalize the tension
on the two cables. There are two sets of stops in the system; the stops in the carrier slots
against which the carriers rest (M in Figure 4-4A), and a stop to prevent the solenoid from
being pulled out of its housing (not shown). The adjustment of the pulleys must be made so
that the carriers will still come up against their stops while the solenoid is not against its
stop. The two cables should not be under high tension when the carriers are against their
stops (the position they would be in just before pulling an electrode).
P-97 FLAMING/BROWN MICROPIPETTE PULLER OPERATION MANUAL – REV. 2.43 - DOM (20161118)