Making the Mold

In 1981 I drove down to Union, Illinois to meet and talk with
Larry Donley at his phonograph museum.  I had spoken with him
on the telephone a few times in regards to my ongoing Edison cylinder
recording project.  He had said that he could help me with this project
so I went to see him.

When I got there, Larry showed me in to the museum and led me to a
glass case that had some cylinder molds inside.  He opened the case
and got out two molds and set them down on a table.  He gave his
permission to me to measure them and make the drawings right there.
These molds were of two different styles, and I picked the one that
looked to be the most likely to be able to be made fairly easily and
also might actually work right too.

It took a few hours to get everything measured using the dial calipers.
Then it all had to be checked to make sure all dimensions were correct
on the sketches.

As I was working, Larry walked over a few times and asked me how it
was going.  One time he came back with a book.  The title of that book
was "Technical Handbook of Oils, Fats, and Waxes", published by
Fryer and Weston, Volume 2, Camridge University Press, 1939, first
edition 1918, Reprinted 1920, 1939.  Larry set the book down on the
table and told me there was something inside of it that I might be
interested in:  This book contains a formula for making cylinder
recording wax from raw materials.

So, after measuring the mold and checking the drawings, I went
about hand copying the wax recipe out of the book. Larry did not
have a copy machine, there was not one close by, and of course,
he did not want to let this book out of his sight.  I still have those
5 pencil written sheets from that day at Union.  Those 5 sheets have
been the most valuable reference in this whole project.  Those molds
in the display case at Union, I have heard, belonged to
Clarence Ferguson at one time. It is unclear to me whether these
molds were used at the Edison laboratory, or whether Clarence made
them.  I have heard it both ways over the years.

After getting home and studying over the mold sketches, I started
making comparative measurements of the Edison phonograph mandrel
and the Dictaphone shaver mandrel and seeing how those numbers compare
with the measurements taken from the mold at Union.

Back then, at that time, I had the idea that I wanted to cast plain
simple "smooth-bore" cylinders and I also mistakenly thought that
if the mold core was made to the exact correct size, that one could
get away without reaming the castings.  Such was my lack of
knowledge at that time, but it was a start.

One of the first things I noticed about the mold measurements was
that the large diameter end of the mold core (the mandrel) was
1.930 inches.  That did not match at all the taper of neither the
shaver mandrel nor the phonograph mandrel.  The mold showed
1.930 inch diameter on the big end, 1.7 inch diameter on the small
end, and an overall length of 5.635.

I could go into quite a bit of math here, but the way it worked out is
that on the mold drawing, the 1.7 inch diameter of the small end of
the core is correct.  Then, in order to make it have the same taper
as the phonograph mandrel and the shaver mandrel, the mold core
on the large end must be 1.872, not 1.930!

It is, still to this day, a total mystery to me how such a mold ever was
made.  At best, a blank cast in it would need a whole lot of reaming!
 I checked, rechecked, double-checked, then checked again, and
kept on seeing that the only way to have a proper mold would be to
change that dimension from 1.930, down to 1.872 inch diameter.
I made the change to the mold sketch, and then noted the whole
history of why that change had to be made.  Other than that, the
mold looked like it might actually stand some outside chance of working.

How the mold finally ended up being made is a story all by itself.
A friend of mine who enjoys electric railroads, interurbans, and
streetcars as I do told me to go see a friend of his at a machine shop
in the near north side of Milwaukee.  So, taking his advise, I drove
over there one Saturday morning to meet the owner Paul Ottman.
I brought the mold sketches and walked up the the brick building that
had "Ottman Engineering" emblazoned in tall black painted metal
letters fastened to the bricks.

It was a big two story building that took up about half a city block.
It was furnished with a lot of heavy machine tools on both floors.
At one time it was a very busy factory.  But, by the time I arrived
there in 1981, it was empty.  All the tools were still there just as
they had been since the 1940s.  But the workers were all gone.
By the time I got there it was just Paul the owner and his sidekick
"steamboat" Joe Albright.  Joe is a very intelligent machinist and
mechanic.  Joe had been in a serious automobile accident many
years before, and so he had a slightly unconventional outlook on life.
Joe always wanted to talk about "spuds" growing out of people's heads.
He had a deep scar on his forehead from the accident.  Paul Ottman was
Joe's friend and Paul kind of looked out for Joe.  They were the entire
workforce of the big empty "Ottman Engineering" factory by the time
I got there.

After introductions, they showed me Joe's home built steam car.
Finally after several hours I showed Paul the mold drawings and he
said "Yeah, we can make that tapered core on my weak-sister of a lathe".

Then Paul and I walked all around various parts of the old empty factory
finding stock pieces for the mold.  He said it might take a while, but that
if I was patient, that eventually it would be done.  Paul never even discussed
money with me.  He said "Bring the Edison machine over some time and
play The Laughing Song".

It did end up taking about two years of frequent evening visits to
Paul's shop to get it done.  Paul had many friends who would stop
by in the evenings and they all sat around in rocking chairs right in
the shop and talked all evening.  A typical visit for me would be
I'd get there about 7 pm and by 9:30 or so, we might take one quick
cut on a mold part in the lathe, then knock off by about 10 pm.

Finally though, it was as complete as it ever would be during that era.
The mold base was complete.  The core was complete.  The outer cylinder
was just a piece of seamless steel tubing of the correct outside
diameter and length, but the inside was an eighth-inch smaller than
the boss diameter on the base.  That outer cylinder needed to be
bored out to 2.254 inch diameter, and the ends finished square and flat.
That last step was never done at Ottman's.  The mold left Ottman's
needing that cylinder to be bored out.  It sat like that, rusting away
from 1982, until summer 2009.  27 years it sat unfinished.  The wax
recipe from the book sat in a folder waiting.

Turned out that Paul Ottman made his fortune during World War II in the
1940s.  He and his workers made parts for the Norden bomb sight at
that factory.  They had a large staff of workers who worked all three
shifts making those bomb sights.  Meanwhile, our airforce bombed
Germany to a pulp using those new technically superior bomb sights.

Paul Ottman liked to tell stories, and I liked to listen to them.
Joe would have his steam car fired up on Friday nights and sometimes
he'd go tooling off with it on Milwaukee city streets up there around the
local 50th and Villard Ave. neighborhood.  His usual excuse was that
he had to drive it over to the bar to set up to do a corn-boil using
the boiler water the following Saturday.   That thing had a vertical
boiler on it that came from an old laundry.  The boiler was right
behind the driver's seat, it was all out in the open.  Joe would go
tooling down the street with it, absolutely quiet except for some
slight hisses of the steam escaping from the cylinders, and, of course
great plumes of aromatic black coal smoke poured out from the stack.
The local police all knew Joe and would sometimes give him
friendly warnings about not driving it on the street too much.
"Spuds" Joe would say.

Almost a footnote: Finishing the Mold

So now there is a jump-cut in the film that cuts out 27 years.
In 2009, I started looking at the mold again and cleaned off the
surface rust.  Started calling around and talking to people about finding
a machinist to bore out and face off the mold cylinder.  After some
digging, I found another old-timer named Keith Dolly who has a small
1940s style machine shop in Clinton, Illinois.  I took the mold over
to him and showed him the drawings and how the cylinder fits the base.
I explained that it needs to be liquid-tight of it's own weight only,
as it rests on the base.  He had it finished two weeks later.

Next segment:  First tests of the mold.

Click here for the mold drawings