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Neumade Film Measuring Machine

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Neumade film measuring machine.JPG

The Neumade Film Measuring Machine is a frame counter designed to measure film during inspection. The most common model is the M-38-S, which has a single sprocket and measures film in both feet and frames. Neumade also manufactured a variety of other frame counters, including multi-gang models to synchronize film for editing, models that counted sprocket holes in addition to feet and frames, models that only counted footage, and dual-format 35/16 models.

The standard M-38-S design is a benchtop model intended for use with Neumade rewinds, which have spindles facing away from the operator. The frame counter is attached to a board, which is positioned on the rewind table to align it with the film path.

The machine can also be adapted for use with Kelmar rewind tables, on which the spindles face the operator and the film path is off the edge of the table. In order to position the Neumade film counter in the film path, Kelmar manufactures a mounting bracket to attach the counter to the front of the table. In addition to correcting the lateral alignment, the bracket also tilts the frame counter back to match the tilt of the Kelmar rewinds. The benchtop design should not be used with a Kelmar table.

Use

Open the right hand guide roller and place the film on the sprocket, avoiding contact between the picture area and the sprocket or roller. Align the film with the frame line on the sprocket, and make sure to place the inboard edge of the film above the post on the roller arm that holds the top of the spring. Lower the roller arm, taking care to walk it back so that the spring doesn’t snap the arm into place. The plastic guide rollers are easily damaged if allowed to snap back into place because the flange may strike the edge of the sprocket.

Open the left hand roller, and place the film beneath the roller in a similar manner. If mounted on a Kelmar table, also take care to avoid contact between the film and the left edge of the casting. The spindle is only slightly higher than the machine, so any drooping film is liable to make contact with the left side, especially when using a heads-out, emulsion-out wind since the feed reel will be spooling counter-clockwise.

Provide some slack on the film, and roll the sprocket until the frame line that will serve as the starting point is positioned between the rollers, and reset the counting mechanism to zero. Rotate the reels by hand to remove and slack, and slowly wind the film until the end of the section being measured.

Excessive noise may indicate a problem. Check your alignment.

Maintenance & Calibration

Film path alignment

  • Benchtop - The frame counter should be positioned so that the sprocket is placed within the film path between the feed and takeup rewinds.
  • Kelmar mounting bracket - The mounting bracket is attached to the frame counter by two screws. Loosen both screws, and position the frame counter in the film path. Adjust the lateral alignment and angle, and tighten the outboard screw, which is accessible when the frame counter is mounted on the table. Run test film through the machine to check the alignment and recalibrate as necessary. After the alignment has been set and the outboard screw has been tightened, remove the machine from the table and tighten the inboard screw.

Roller arms

  • The roller arms should be adjusted to provide adequate clearance between the guide rollers and the sprocket. Typically, this can be accomplished by adjusting the stops that set the gap between the rollers and the sprocket. However, it may also be necessary to set the lateral alignment by adjusting the screw that connects the roller arm to the casting.
  • Spring stops - Check for clearance between the guide roller and the sprocket. Both should spin freely without making contact, and the gap should be at least as wide as two layers of film. If the gap needs to be adjusted, loosen the nut on the screw that makes distance between the roller arm and the stop block on the casting. Adjust the screw to the appropriate point and tighten the nut.
  • Lateral alignment - Before making any adjustments to the roller arm, first check the lateral alignment of the sprocket, which should be pushed back against the casting. If the sprocket is properly aligned but the roller flange binds against the side of the sprocket, the lateral alignment can be calibrated by adjusting the screw that connects the roller arm to the casting. If the screw has to be backed off enough that it develops excessive play, the screw can be secured by applying blue Loctite to the threading.

Lubrication

  • There is an oil point just behind the spindle. Apply a couple drops of a light oil. Traditionally an oil readily available in the booth such as Simplex projector oil would be applied, but synthetic oil is preferred.
  • Open the door on the back of the casting to grease the gears. A synthetic lubricant such as Super Lube synthetic grease should be used. If old grease has hardened on the gears, the machine should be disassembled, cleaned, and relubricated.
  • Depending on the climate, the plastic guide rollers may not require lubrication. However, if humidity is a concern or if corrosion is found when cleaning the roller shafts, lubricant may be applied for hydrophobic purposes. An aerosol silicone lubricant is ideal for this purpose, as it applies a very thin coating and does not attract dirt like liquid lubricants. Apply the silicone and wipe off any excess. Liquid lubricant is not recommended for use with plastic rollers, and petroleum based lubricants have solvent properties that will eventually eat away at plastics.

Cleaning

  • Clean the rollers and sprocket with a toothbrush or with alcohol if necessary.
  • Clean dust behind the roller arms, beneath the sprocket, etc. Dust tends to accumulate in these hard-to-reach areas.

Full Breakdown

Disassembly:

  1. Remove the door on the back of the frame counter, which is held on by two screws.
  2. Loosen the set screw on the sprocket and remove it from the shaft.
  3. Push the sprocket shaft into the casting and remove it through the door.
  4. Disconnect the counting mechanism from the casting. Loosen the two screws on the right side of the counting mechanism, and remove the two screws on the left. Slide the counting mechanism to the left to remove it.

Reassembly:

  1. Reinstall the counting mechanism on top of the casting.
  2. Insert the sprocket shaft through the door on the back of the casting. Rotate the shaft so the flat side faces up.
  3. While applying pressure to the gear at the end of the sprocket shaft, place the sprocket on the shaft with the set screw aligned with the flat side of the shaft, and push the sprocket against the casting. Tighten the set screw.
  4. Relubricate and check for smooth action. The sprocket should spin freely without resistance.