TS440 Case Screws binding in the heat sink

Occassionally a case screw that fastens to the heat sink of the TS-440S will cross thread or bind when it is being inserted or removed.
Binding may be caused by tooling marks on the screw or by burrs on the tapped threads in the heat sink. When a screw starts to bind,
DO NOT TRY TO FORCE IT! as this may cause the head to shear off. If the screw is being removed and it starts to bind, return the
transceiver to KENWOOD. Do not make attempts to remove the screw. In addition, if a transceiver is being brought to you with a scrw
sheared off, return the unit to KENWOOD. Do not attempt to drill out the screw.
If a screw starts to bind when it is being installed, carefully back it out. Inspect the screw for marks or burrs and replace it if it is
questionable. Since the threads in the heat sink may be causing the screw to bind, they should be cleaned by running a 3 x 0.5 mm
tap into each hole.
The tap is inexpensive and can be obtained at may of the larger hardware stores.
To avoid cross threading, make sure the covers are properly aligned when they are being installed. Proper alignment means that there
is a clear path for the screw to turn into the heat sink.
This assures that the screw does not rub against the case and result in it turning into the heat sink at an angle.

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GW1NGL NA7KR Kevin Roberts Ham Radio

Page last updated on 09/10/2012 by Kevin Roberts NA7KR a colection of Ham Radio and Electronic Information