Download FCC4 Fast Clock Controller

Fig. 5: Clock hand sizes (actual size).
It is important to use the supplied Klockit hands for several reasons:
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They fit the Quartex Q80 movement. Hands on many inexpensive clocks attach to the movement's
shafts differently, and can't be used on a Q80 movement. The Klockit minute hand's hole has two
flat sides (see Fig. 5) to fit the flatted shaft on the Q80 movement.
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They are lightweight metal, and modified movements can move them at high speed. Thicker plastic
hands found on some commercial clocks have too much mass, even if they could be made to fit the
Q80 movement.
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You can't use a second hand. The movement doesn't have enough power to rotate a second hand at
high speed. This is not a consideration when buying a Q80 because you don't get a free second
hand from Klockit or from me. But frequently commercial clocks have a second hand, and it might
be tempting to use it on your fast clock. Don't.
Choosing clock hands
For best appearance, the minute hand should extend to the "time ring" where the tick marks are
printed. Usually the numerals are inside this ring, so the minute hand extends past the numerals.
The maximum recommended length of the minute hand for fast-time use is 3½". A minute hand longer
than this can cause the modified movement to operate erratically.
This means that the clock's time ring should be no more than 7" in diameter. The clock face itself can
be larger (and most are), but the time ring should match the minute hand length. You can snip off the end
of the minute hand if it's too long for your clock's time ring.
FCC4 Fast Clock Controller User Manual
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