
I do have some friends/colleagues, though, who have that capability and are ready to scan my Edison stylus, etc. once I'm truly ready to throw in the towel.
Those little drills are known as "wire drills". The #71 you mention is 0.026 (twenty-six thousands) inch diameter. You can find a complete chart of wire drill sizes here: http://www.custompartnet.com/drill-size-chartDiscman wrote:For stylus pins I use tiny steel drill bits I purchase at my local hobby shop. The size I usually get is a #71. I'm not sure what that number means. Take your stylus to a hobby shop and test fit until you get the right size. You'll have to cut the bit to the correct length. I usually buy ones that are slightly larger than I need and then reduce the diameter by turning the bit in an electric drill while I squeeze fine sandpaper around the shank. With a little trial and error you can get a perfect fit.
Dave Jolley
Great observation, Chuck. Not only is the weight of the reproducer a factor, but also the full weight of the horn system is employed. When lowering the stylus for playback the horn is supported vertically with a rather substantial shaft that pivots at its' lower end in the cabinet and its' top end at the top plate. If the height isn't adjusted properly, it's easy to understand how the stylus bar link and/or the diaphragm could be overwhelmed by the weight of it all. Of course the reproducer weight has only so much travel and would limit its' vertical travel, but still, a lot of weight is a lot of weight!Chuck wrote:Ralph,
With all due respect to you and everyone
else here, who are using and enjoying Edison
Diamond Disc machines, here is my take on it.
I'm still on the outside looking in, as I have
not yet gotten any Diamond Disc machines.
I've been looking at them for many years
and still have not found the right one.
What I do know about them is this: The pressure on the stylus is immense! That weight is about the heaviest darn thing I've
ever seen, and the very fact that any
phenolic resin compound could ever be found
which can stand up to that pressure even
for a few plays, is simply remarkable!
(Or is it markable?) Pun intended.
What I'm getting at here is that as we all
can easily recognize, this system must be in
absolute perfect condition in order for it
to work right and not instantly destroy
the records.
Here's a few very humble suggestions I have.
Dave's idea of using the #71 drill bit as
a pin is a very good one. The more precise
the pin fits, the better off the whole system
will be.
I myself would not attempt any such repairs
without at least having a dial calipers handy
to measure the diameter of the pin, so I can
see what I'm doing.
Go to http://www.mpja.com to see a few
very reasonably priced sets of dial
calipers.
Looking in from the outside on these Diamond
Disc machine issues gets me thinking about it
in the same terms as the fitting up and
adjustment of an automatic recorder.
There, the same sort of a situation is at
hand. There must be a precision fit of the
pin for the stylus bar and also a similar
fit for the swinging weight pivot. Both must
be perfect in order for the thing to work
right.
The absolute minimum required tools to work
on stuff like this is a set of dial calipers
so you can see what you're doing.
I like Dave's suggestion of turning the
pin in a drill-chuck, and sanding off
a few tenths of a thousandth off the outside
diameter, in order to gain the exact fit
you want. A micrometer would even get
you a bit more accuracy, but a dial calipers
will do. You can get a set from MPJA for
less than 20 bucks.
Again, I really am in awe of what you guys
are doing with these DD machines! They sure
sound great when they are working right, but
jeez....THAT is a LOT of weight!!!
I hefted the weight of a Dance reproducer
one time, and I simply could not believe
how massive that weight is on there.
Has anyone ever attempted to calculate the
point-loading in PSI when that diamond traces
across that flat surface in the runout area?
Whatever it is, it's got to be way, way up
there!!! It's simply a miracle this system
works at all, in my extremely humble view.
Chuck
HisMastersVoice wrote:Ralph,
I've been having similar problems as well. I was going to start a thread about it, but I think I'll just join yours if you don't mind.![]()
My reproducer has an original diaphragm, new gaskets, a cleaned and oiled floating weight pivot, and a perfect diamond that was checked under a microscope. The limit pin rides perfectly in the center of the loop until it exits the final groove, then the floating weight shifts to the left (if you are standing in front of the machine) and the pin is in contact with the loop at that point. Before I changed the stylus, I was noticing some record wear, which seemed to stop after installing the new one. However, now I am noticing scoring on the "dead wax", which did not happen with the old one. This happens on most but not all discs I have tried. The only thing I can see that isn't as it should be is a slight side to side play on the new stylus bar. I put a small dab of grease on each side of the stylus pivot to reduce any possible lateral vibrations, but that didn't seem to have any effect on the scoring. Other than that, the reproducer sounds fantastic and I'm not noticing any wear on the grooves. Should I be concerned? (I am...)
Thanks, Edisone. But I have to disagree here. I've seen plenty of DDs that show plenty of use but still have clean (no scoring) run-off areas. As for my statement about the stylus bar being tucked between the shoulders pretty firmly--well that's true, but every time I reinstall it I make sure it flexes adequately--and I too have sanded it to make sure that it moves freely.Edisone wrote:Somewhat random thoughts:
Slight marking on blank parts appears on almost every Edison disc I've ever seen - it's missing only on never-played dealer stock. Damage to records will appear as scrapes in the grooves & grit collected on the diamond, and heard as extra surface noise when playing. I suspect that the faint lines on blank parts are just the scraping-off of a waxy coating or the varnish ingredients of lead resinate ("ShinO") or Sandarac.