Practice Tips #15: Peri Pro Transport Repairs - Mystery of the Missing Film

Peri Pro Transport Repairs: How to Solve the Mystery of the Missing Film

The Peri Pro film processor uses a film “transport rack” that utilizes a system of arms and gears to push the films along eight grooves on the inside of the rack. The films travel through the developer, fixer, and wash tubs to the dryer/heater assembly. Film dries and then deposits into a film “catcher” at the back of the machine.

Film sizes #0, #1, #3 and #4 are placed inside a film carrier to move them through the transport. Unless these films are placed inside the carriers incorrectly or the transport rack or processor itself has an issue, these films rarely get lost. However, the #2 films travel freely along the eight grooves without a carrier to guide them. These films sometimes “mysteriously disappear.” In this edition of Practice Tips, we would like to help you solve the mystery.

Reasons Why Films Sometimes Do Not Exit the Peri Pro


One of the most common causes for lost films. Be sure to follow a regular cleaning and maintenance schedule for your Peri Pro transport rack. If you do not, chemistry builds up in the grooves causing the films to pop out of the rack.

We suggest paying special attention to the area at the chemistry line above and below where the smaller “L-arms” turn. The chemistry tends to dry and build up there. Use a toothbrush and thoroughly clean the grooves of your rack as well as the gears on the back of the rack. Do not use anything abrasive. There are kits available with a special brush and tub. Follow manufacturer recommendations for cleaning and maintenance.

NOTE: Do NOT “drop” your transport rack into chemistry tubs when placing it back into the unit. Do NOT splash the chemistry when refilling the tubs, as you may contaminate the chemistry. In addition, the chemistry can get up into the area where the shutter plate sits causing it to stick.

Chemistry also corrodes the shutter plate extension spring causing it to snap. Your shutter plate will no longer move and your films will not drop when they are supposed to. To replace the spring and clean under your shutter plate you will need to remove the three top plate pins to gain access to the shutter plate area.


Broken or missing teeth on the rack gears or even the Main Drive Gear, (which engages the rack) can cause it to skip and will in turn knock the films out of the rack. Make sure to check the gears on the transfer arm assemblies on the open side of the rack, as well. All of these gears are replaceable. Any time you remove a gear from the Peri Pro transport rack, the drive arms and timer gear need realignment.

The Main Drive Gear is located on the inside wall of the Peri Pro behind the fixer tank. This gear holds on by a 3/32” allen (hex) set screw. When replacing this gear, make sure you get the appropriate gear for your Peri Pro. Gears vary in size accordingly to each model of the Peri Pro.


If your drive arms are out of alignment, you will lose your films every time you send a batch through. Realigning drive arms for the Peri Pro and Peri Pro II transport racks will be done in the same way. However, realigning the arms for the Peri Pro III will be slightly different. You will also have to be aware of where the “dot” on the Timer Gear points (gear is located on the back of the transport rack near the shutter release assembly) when realigning to make sure the shutter opens and releases films at the right time. Please see the diagram below:


If your films are bent, straighten them out before feeding them into the transport. If films are jagged, try feeding the jagged side in last. Do the same thing with the small raised “dot” or “dimple” on one of the corners of #2 films, as well. Make sure to feed the #2 films into the processor with the “Film Inlet Grill” in place. The grill helps align the films with the grooves in the rack.


  • Dryer Drive Motor Not Turning: If the dryer drive motor does NOT turn, the rollers that move the films through the dryer heater assembly won't turn as well. The transport rack still turns as it is driven by the main drive motor. This may cause the films to fall down on to the heater assembly and in turn burn out the heater assembly. You will need to replace the dryer drive motor. If losing films in the dryer, make certain to check your heater & heater fuse (or thermostat) as well in case films have melted on the heater causing it or the thermal fuse/thermostat to burn out or blow.
  • Main Drive Motor not turning: Make sure that you have power to the unit. Is the rack sitting squarely on the drive gear? It can be easy for the fixer tub to get in the way. Does the main drive gear look broken? Is the drive shaft turning? If it is not, replace the main drive motor.

1 comment

  • William Ditchkus

    I have 3 peri pro ll transports that need to be refurbished . Does your company do this? Thank you very much. Dr Bill Ditchkus Toms River Nj


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