SB1012 - IFBR1a Battery Door

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When using 9V Li-ion rechargeable batteries, (approximately .06 longer than conventional alkaline or Ni-metal hydride rechargeable batteries), the longer format battery requires a greater door closure force to counteract the increased battery contact spring forces involved.

Tools You Will Need:

  • (1) 26150, Compression Spring
  • Small phillips screwdriver
  • Loctite® 290 (or equivalent) threadlocker

SB1012 Photo1


  • Step 1: Remove the three (3) screws that attach the battery door assembly from the bottom of the case.

    SB1012 Photo2

  • Step 2: Remove the central screw at the battery door rotational axis. This will require holding the opposing brass spring-keeper nut with your fingers or pliers to overcome the holding torque of the thread lock
    adhesive present there.

    SB1012 Photo3

  • Step 3: When the screw is fully removed the five (5) component parts shown will come loose.

    SB1012 Photo4

  • Step 4: Discard the compression spring and then reassemble the battery door assembly, just as it came apart, with the stronger (brite) 26150
    spring shown below on the right.

    SB1012 Photo5

  • Step 5: Use a very small drop of Loctite® 290 threadlocker on the internal threads of the spring-keeper nut. Hold the nut fixed while tightening the screw until the flanged end of the nut measures ~3/16” (.188) above the near surface of the base plate.

    SB1012 Photo6

  • Final Step: Install the revised battery door assembly into the bottom of the case using the same three (3) screws removed at Step 1.
    The newly installed compression spring will impart 35% more door closure force to ensure full seating of the battery door against the lower edge of the case when rotated into the closed position against a 9V
    Li-ion rechargeable battery.