[Jan Derogee] pulled out his phonograph the other day to hear the 100+ year old wax cylinder warble of “It’s a Long Way to Tipperary”, but couldn’t locate the reproducer — this is the small circular bit that holds the stylus and transfers the groove-driven vibrations to the center of a thin diaphragm, which vibrates into the sound horn. It’s easily the most important part of a cylinder phonograph. What do you do when you lose your reproducer? You could search ebay for a replacement, but that wouldn’t be nearly as fun as reproducing your reproducer yourself.
Traditionally, diaphragms were made from mica or celluloid, and the Edison disk phonograph used seven layers of shellac-soaked rice paper. Reproducers typically have a Dagwood sandwich of gaskets surrounding the membrane, but they don’t have to be so convoluted to work — a single strong membrane will do just fine. Just ask [Jan], who made a new reproducer with a 3D-printed case, a hand-pulled glass stylus, and a disposable aluminum foil pan for the diaphragm.
It’s difficult for us to say which part looks more fun — stretching the glass shard over a gas kitchen stove with the flame focused by a stack of wrench sockets, or cutting up a bicycle inner tube and using a car jack to press the aluminum into shape against a 3D-printed mold. The whole video is awesome and you can check it out after the break.
As [Jan] notes in the video and on the project site, the glass stylus should really be made from borosilicate because it’s harder than regular soda lime glass (that’s why they often make vaccine vials out of it). Regular glass will work and takes much less time and gas to reach the pull-able stage, so that’s what [Jan] used in the video, but it will wear out much more quickly. Fortunately, this was a temporary solution, because as soon as [Jan] made a replacement, the missing reproducer showed up.
Please let that cat’s name be “Nipper”…
B^)
“as soon as [Jan] made a replacement, the missing reproducer showed up.”
This is a surprise? I thought this was a Law of Physics like thermodynamics or something…”As soon as a replacement for a missing item is purchased, the quantum uncertanty state of the original item is collapsed back into this reality…right in front of you.”
Kind of like that lost sock.
Can these be cheaply reproduced? I have more cylinder machines than I do reproducers and could use a few!
The author of “It’s a long way to Tipperary” was writing about his father’s farm in North Dakota. Which was named after the Irish city.
The construction steps are well and truly awesome. Making a custom bellows, glass blowing using socket-wrench sockets, the whole thing speaks to “figure out a creative way to do it”.
I suspect he secretly knew where the missing part was, but used its disappearance as a pretext to do cool stuff.
My understanding was that borosilicate is more fragile than soda lime glass, and the reason it’s favored in the lab is the low coefficient of thermal expansion.
and the higher meting temperature…
I love it. Great!!! I will try to make one myself.