[hank alrich]

The grill of one of my M160's has taken a dent. It doesn't affect the
performance, but I find it distracting. The tiny screws under the red
dots don't seem to want to respond to my screwdriver.

Just in case: are they reverse thread?

If not, and it's just that they have never been removed (I bought these
new in 1975; had 'em rebuilt in Germany in 1982 after lots of use at
onion audio and onstage at Armadillo World Headquarters), can I put a
tiny droplet of something like WD-40 on them to try to get them to give
it up for me?

--
ha
shut up and play your guitar

[Mike Rivers]

hank alrich wrote:

Just in case: are they reverse thread?

They're standard right-hand thread, but they're very tiny and the slots
aren't very deep. I also think they may have some sort of locking
compound on them. I had a similar problem getting an M-260 open. Having
a really good screwdriver helps. I took mine over to a friend with a
well equipped shop and a full set of Wima screwdrivers. When he found
the perfect fit, the screws came out (with a little difficulty). At the
time, Beyer had a cooperative parts department and, when I lost one of
the screws, they sent me a few for free.

Sometimes just knowing that it's possible helps to get a difficult job
done. That's about all the help I can offer.


--
If you e-mail me and it bounces, use your secret decoder ring and reach
me he
double-m-eleven-double-zero at yahoo -- I'm really Mike Rivers
)

[hank alrich]

Soundhaspriority wrote:

"hank alrich" wrote in message
...
The grill of one of my M160's has taken a dent. It doesn't affect the
performance, but I find it distracting. The tiny screws under the red
dots don't seem to want to respond to my screwdriver.

Just in case: are they reverse thread?

If not, and it's just that they have never been removed (I bought these
new in 1975; had 'em rebuilt in Germany in 1982 after lots of use at
onion audio and onstage at Armadillo World Headquarters), can I put a
tiny droplet of something like WD-40 on them to try to get them to give
it up for me?

That is an interesting problem, which I encountered in movie camera repair.
The optimal chemical depends on what's holding the screw. WD-40 is never
optimal. If the screw is held by oxidative corrosion, a penetrating oil is
the thing. But an old camera repairman explained to me that in many cases,
the screw is stuck by paint. He very patiently dripped acetone from an
eyedropper on the screw until it gave up. This takes patience, because the
acetone evaporates almost instantly.

If the screw is held by a threadlocker, I think acetone might still be
optimal. There are different types of threadlocker. One very politely gives
up when you finally exert enough force with your Wiha screwdriver (and I do
hope you're using a Wiha, not a carbon-steel Radio Shack job). If, however,
the threadlocker is one of the high strength formulas, it's a specialist
job.

Acetone worked for me on Angenieux optics. Maybe it'll work for you.

Hank, I'm sure you know this, but from what I've read, even a mild breeze
can break an exposed ribbon. I would leave it alone.

I should talk; it would drive me crazy, but it's your mike

This is not my first adventure into the innards of a ribbon mic.
Interesting thing is that this query posted into K Heine's forum at PSW
drew but a single comment, and nothing at all from the "experts". Guess
since it's not some fake U47 they don't know anything about it.

Thanks for you comments, Bob.


--
ha
shut up and play your guitar

[hank alrich]

Mike Rivers wrote:

hank alrich wrote:

Just in case: are they reverse thread?

They're standard right-hand thread, but they're very tiny and the slots
aren't very deep. I also think they may have some sort of locking
compound on them. I had a similar problem getting an M-260 open. Having
a really good screwdriver helps. I took mine over to a friend with a
well equipped shop and a full set of Wima screwdrivers. When he found
the perfect fit, the screws came out (with a little difficulty). At the
time, Beyer had a cooperative parts department and, when I lost one of
the screws, they sent me a few for free.

Sometimes just knowing that it's possible helps to get a difficult job
done. That's about all the help I can offer.

Thanks, Mike.

--
ha
shut up and play your guitar