The Talking Machine Forum — For All Antique Phonographs & Recordings

I was told at Union that I was close to having it, by a very respected David Giovannoni. This made me want to finish them up as they should,I decided to make them more authentic so now they have the double helix spiral, I have the right handed mould working well. Maybe none of you noticed this, but Edison's have a double helix spiral, and Columbia blanks have a single spiral that is the same thred count as the Edison. Not only that The double spiral helped the ejectomatic work on the Ediphone blanks too, So now I can make those business machine blanks as a regular product. I used the mould for the first time today and made 5 standard, and one Ediphone blanks. What does that spiral do and why do brown wax have them?
1. they make it easier to ream as you only have to take wax off of the spiral.
2. The spiral keeps dust off the interior of the record making it fit the mandrel more accurately.
3. The spiral relives stress when a record is in the mold, in fact I have never had a spiral core cylinder crack in the mould unless I put it in the freezer on purpose, or forgot which way to turn the core (I have a right and left handed cores.) Most importantly it makes it easier to release the record from the mold, You can unscrew the core from the expanded cylinder, it does not bind as much and even blanks left on for several hours will unscrew and not be cracked.

Here is some photos of recent production of brown wax blanks. There is 103 new blanks in this photo, this represents work from this summer. I work on cylinders about 3 days a week from 2-6pm on work days and 12-7pm on days off. making from 6-20 blanks per session. These are made from composition 1046 which was used from 1889-the end of brown wax blank production. As you can see just about every color variation from white to black, but are made of exactly the same materials and amounts. I have been reading that various methods were used to heat the wax in the old days, some batches were made with a coal fire beneath a cast iron kettle, some an oil burner, and some natural gas. I have found that by using different methods of heat, and how long the wax is cooked, results in different colors in wax, some of this has to do with oxidization of the wax the longer it is cooked, a batch that starts out white, may be a medium brown after a day of moulding, and then if the wax is used for a week results in almost black records (with NO lampblack or additive to make them black) heating just darkens them that much. I will have to make a youtube video of how this happens.

Chapter XIII of "The Manual of the Phonograph" page 118. The Edison record of to-day is commonly termed a "wax record." There is nothing in its composition that justifies the term, however, as the principal ingredient in the mixture from which the cylinders are moulded, is stearate of soda, a white chemical compound, hard and semi-transparent. These Cylinders vary in color, from white to dark brown, caused by varying condition in the process of making. The difference in color has no bearing whatever on their quality. They are all of the first grade. In fact, no other than the first grade is known at the Edison Works. The cylinder as it is first moulded is known as a blank. The Edison blank is chemically pure. It has no successful rival in the market. There is no talking machine company or infringer who does not recognize the fact and there are no records worth having, that are not made on Edison blanks. Other kinds are gritty, harsh and unserviceable, and little if any cheaper. As delivered by the factory, blanks do not have surfaces prepared for receiving a record. It is necessary to shave off one or two turns to secure a perfectly true working surface. All Phonographs except the Gem are furnished with a device for doing this. When once trued the cylinder always remains true.


Concert records are interesting, it seems they are totally opposite of