Century JJ

The Century JJ is the only Century projector that can project both 35mm and 70mm.

Avoiding film damage

The most common form of damage caused by Century JJs are slap scratches, which appear as small tic marks on screen, usually in clusters if a print has been run several times on the same projector using the same threading pattern.

Slap scratches occur in two areas: the upper and lower loop. In the upper loop, 70mm prints can get slap scratches by hitting the upper 35mm roller, especially if the loop is too small. To avoid this, remove the 35mm roller and replace with a second 70mm roller.

The lower loop is more complicated. Most Century JJs have a roller underneath the intermittent that acts as a stabilizer and prevents the film from hitting the top of the intermittent casing. Some projectors have additional rails that work to stabilize the lower loop, and consequently make it run more quietly.

Resources

• Century JJ Instruction Manual (1959)
• Century JJ Parts Manual (1959)
• Century JJ Installation Instructions (1960)
• Century JJ Installation Chart (1959)
• Century JJ Threading Diagrams
• Century JJ Brochure (1959)
• Century JJ promotional article by Larry Davee (1959)
• Century JJ article from Box Office Magazine (1959)

External Links

• Film-Tech manuals page - Later versions of the manual for the the Century JJ (1999) and JJ-2 and JJ-3 (1984) are available here.