Cutting Mono Non-microgroove 10" 78 RPM Records

[jsthomps]

Hi Everyone,
I own a small collection of Golden Age (1938 - 1949) jukeboxes all which play shellac 78 records. The jukebox hobby got me into collecting shellac 78's. I mostly collect big band and 50's eras. Some of the famous jukebox hits like Patsy Cline's "Crazy" were never released on shellac so I started thinking whether it would be possible to cut my own. My research led me to this amazing forum. I am a DIYer and I would like to attempt to build a cutting machine. I'm capable when it comes to CNC projects, processors, and electronics but I am a newbie when it comes to mono cutting head designing and building. All my jukes use 3mil sapphire styli so I researched grove dimensions and came up with this:

• groove depth 3mil
  groove width 6 to 7mil
  groove angle 84 to 88 degrees
  groove spacing 100 groves/inch

I was also planning on doing experimental cutting on DVD blanks which I understand are polycarbonate. Any feedback on my scheme would be greatly appreciated.
Thanks,
Scott

[markrob]

Hi,

Welcome. If you have the skills, time and money, you will be able to get something going. I used to own jukes (Seeburg HF100R, 1930's Seeburg Gem, Rockola' 1438 and a newer Rockola. Had to part with them when we downsized and moved to smaller quarters. I really miss them.

There is one easy to build head design that is detailed here that I think would work well for you. Its stereo, but you just feed it mono and it will be fine for you.

https://www.lathetrolls.com/viewtopic.php?f=15&t=8187

There is also a recent well documented project for the lathe part that should also work well with some mods for your needs.

https://www.lathetrolls.com/viewtopic.php?f=15&t=9187

Feel free to go your own way on this. Its a great learning experience.

I would recommend that you try embossing rather than cutting first as its much easier and less expensive. My concern is if the shallow groves generated by embossing will track well in an old golden era juke at 78. However, if you get that working with a modern turntable/pickup combo, you should be able to transition to full on cutting via a diamond stylus. As long as your groove depth is sufficient, you should be ok cutting with a 1 stylus playing back with a 3 mil stylus at 78 rather than have to get a custom stylus or take a chance on a old used or NOS cutting stylus from the 78 era.

Hope this helps,

Mark

[jsthomps]

Thanks for your feedback Mark!