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CIR M.3-35mm Special

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CIR M.3-35mm Special splicer.

The CIR M.3-35mm Special is an Italian tape splicer manufactured by CIR (Costruzione Incollatrici Rapide) in Rome. In the United States, CIR products were marketed under the brand name CIRO. While common in art house cinemas and archives in the United States, CIR splicers are far more popular in Europe. Other versions of the M.3 can accommodate CS perfs, magnetic tape, and 16mm and 70mm film.

The M.3 is most notable for its ability to accommodate shrunken film. It features adjustable registration pins that can be moved closer together to make a splice without stressing the perforations on film suffering from head-to-tail shrinkage. This has the added benefit of allowing the M.3 to rejoin non-shrunken film that simply has bad cut, without losing additional frames. The registration pins next to the cutting blade can also be retracted, allowing the film to lay flay without without engaging the pins if they no longer line up with the perforations due to shrinkage.

Cleaning

  • Clean surfaces with 99% alcohol if dirty.
  • Keep punches and perforation holes clean and adhesive-free. When adhesive builds up, clean the punch with 99% alcohol and a toothbrush (acetone may be used, but do so with solvent resistant gloves in a well-ventilated area and avoid contact with any plastic or rubber parts).
  • The tape from punched out perforations accumulates in the chamber below the splicer bed. Periodically open and remove tape particles. Use alcohol to degum if necessary.

Maintenance

  • Make sure that the blades are sharp and correctly aligned. They should not be hitting the metal sides of the splicer bed, but they also shouldn’t be leaving excess tape overlapping the film edge. If properly maintained the blades should never dull.
  • Once a year, or if punch action is not smooth, clean and lightly oil the lever pivot pin and the guide posts with a few drops of Esso universal oil. When doing so, remove the perforator assembly and clean the blades and perforator with 99% alcohol and a toothbrush (acetone may be used, but do so with solvent-resistant gloves in a well-ventilated area and avoid contact with any plastic or rubber parts). Always make a test splice after reassembling the splicer.
  • Once a year, or if rust is discovered during cleaning, remove the base plate and lightly oil the threaded shafts that the base plate is screwed into and the flat spring that controls the retractable registration pins.
CIR M.3 partially disassembled for cleaning and lubrication.

Guillotine blade alignment

  • The position of the blade can be adjusted using the two screws on the plate to the left of the splicer blade. These screws compress either a flat spring or a cork-like material behind the plate, adjusting both the angle of the blade and the distance between the blade and the registration pins.
  • To calibrate the angle of the blade, make a cut and then lay the film on the splicer bed, flipping the film (inverting base/emulsion orientation) on one side of the cut. This will exaggerate any misalignment (the long side of the cut will overlap, the short side of the cut will leave a gap). Adjust by tightening/loosening the screws until the angle is straight and the cut is equidistant from the perforations.

Use

  • The CIR M.3 is the ideal splicer for splicing shrunken acetate or rejoining a poorly cut splice.
  • Place repair tape over the center of the splicer bed to prevent surface wear on the film.
  • Always close guillotine blade before laying film on the right side of the splicer bed to make a splice.
  • When laying film on the splicer on a rewind table with spindles facing the operator (ex., Kelmar), the splicer bed should be at the edge of the rewind table, as close to alignment with the film path as possible. For rear-facing rewinds (ex., Neumade, Simplex), the splicer bed should be perfectly aligned with the film path.
  • Always use gloves to touch the surface of the film when making splices. Try to avoid letting the image area rubbing against the various surfaces (rewind table, reel flanges, etc.)
  • The knob on the left adjusts the registration pins on the left side of the splicing bed, reducing the distance between the pins to correct for shrinkage or to compensate for a gap caused by a poor cut.
  • The knob on the right retracts the registration pins next to the guillotine blade to accommodate shrunken film.

Testing for and compensating for shrinkage

  • If the film cannot be placed on the registration pins at the narrowest setting without stressing the perforations, it is too shrunken to run. Note that there is no adjustment for lateral (cross-frame) shrinkage. If the perforations on one side of the film fit easily on the pins but the other side must be forced down, causing stressing in the direction of the film edge, there is too much lateral shrinkage to project the film, regardless of how shrunken it is head-to-tail.
  • When running acetate, test the shrinkage on the head or tail first if it is original. Start with the pins close together and then widen the gap until the film lies flat but is not overly tight. While the rate of shrinkage may change over the course of the reel, this allows you to roughly calibrate the pin distance without unnecessarily handling the picture area. When inspecting a reel composed of multiple shorts or clips, the shrinkage will often vary between them, so each item must be assessed separately.
  • When making a splice, adjust the pin distance so that the ends of film are gently touching with no gap and without overlapping. If the cut is uneven, one side may slightly overlap so that there is no gap on the shorter side.

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