R/E/P Community

R/E/P => Klaus Heyne's Mic Lab => Topic started by: BobSchwenkler on October 31, 2011, 01:46:53 PM

Title: Changing pin on KK84
Post by: BobSchwenkler on October 31, 2011, 01:46:53 PM
How difficult is the swapping of the shorter pin on the KM86 capsule to the longer of a KM84 type?

I perhaps remember someone mentioning that the pin is attached to something inside the capsule that will come loose if the pin is simply removed, am I remembering correctly?
Title: Re: Changing pin on KK84
Post by: klaus on October 31, 2011, 04:48:31 PM
Changing the pin can be tricky: It's glued in place, and re-attaching it without breaking off the threaded portion takes a fine sense of torquing: The M1.2 thread on the gold plated brass thread can easily be over-torqued.[/quote

Here is the procedure:

Place the capsule head, diaphragm down. Do not move it throughout the following procedure, because there is a tiny 6µ aluminum washer between the backplate and its resonator  which is held in place only by the needle's thread. If that washer is dislodged through excessive movement of the unit while working on it, after removing the needle's thread, the game is up.

Take smooth-jawed needle nose pliers and grab the pin close to the entry into the backplate resonator. Turn counter clockwise without angling the pin and putting additional stress on the thread. Unscrew by hand as soon as you feel you have enough torque available in your fingers.

Replace the needle and hand-tighten. Once hand tight, tighten an extra 20º to 30º with pliers, no more.

When done, clean needle with 99% alcohol, then put a drop of Caig Pro-Gold on it and distribute with a rag, removing excess liquid in the process of doing so.
Title: Re: Changing pin on KK84
Post by: BobSchwenkler on November 01, 2011, 12:59:38 AM
Very much appreciated Klaus. I think I may give this a go if I decide to do this capsule makeover.