Bell and Howell 1598, User Manual

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P a n chromatic TQIII & TQIII Specialist User Manual
Page
15
Film problems
32 So reliable is the Bell & Howell film transport system that with films in good condition no
problems should arise either in threading or during projection. Even with faulty films, a
satisfactory presentation will often be possible because of a device designed to reset,
automatically, "lost loops" resulting from the most common forms of film damage - broken
perforations or badly made joins. For other kinds of film fault, there are further safety devices to
reduce the risk of making existing damage worse.
Threading and projection difficulties are likely to take one or other of the following forms

Problem
Film not drawn into projector after being pushed under "4".
Cause
Run/still lever at rear (sill/picture) position, Remedy
Move lever to front position,
Cause
Tip of film bent or otherwise damaged,
Remedy
Use trimmer to remove damaged tip (Stage 15).

Problem
Tip of film enters projector after being inserted under “4” but reappears as shown.
Cause
Failure to set automatic threading lever (Stage 16). Remedy
Reverse projector to remove film and repeat from Stage 16.
Cause
Excessive inward curvature of film (probably due to long storage on a small spool).
Remedy
Remove film as above, correct excessive curvature by coiling the first ten frames of leader
in the direction opposite to the original curve. Repeat from Stage 16.