[Elecraft] KPA100 Standoffs between heat sink and board

[Ben Hofmann K1NT]

Anyone have any insight on this?

-Ben  K1NT



I am slowly progressing on my KPA100.  I am at the
part where the board and heat sink are temporarily
mounted together to provide the proper spacing for
soldering the final transistors.

The five standoffs that go between the board and the
heat sink are all 3/16", however, the heat sink has a
machined depression around the hole for the standoff
that is directly behind the center of the rear panel
when assembled.  Unless I missed it, the manual states
I should not use a washer or lock washer on any of the
standoffs between the heat sink and the board either
on this initial assembly, or on the final assembly. 
This being the case, there is a gap between the board
and this particular standoff.  When I add the
additional standoffs for mounting the shield later on,
this will either prevent me from snugging the standoff
down on this particular stud, or force me to warp the
board at this point in order to get it snug.  Surely
this cannot be the case.  While I haven't measured it,
the depth of the machined depression in the heat sink
would lead me to believe that a washer or lock washer
is intended to be used either between the heat sink
and the standoff, or between the standoff and the
board during final assembly.  Anyone have any insight
on this?

-Ben  K1NT