Pinky and the Brain

3D Printed Adapter for Big-Hole 45 rpm Record

big-hole 45 rpm

Record label issues big-hole 45 rpm vinyl, together with a limited-edition 3D printed adapter in the shape of a pink brain.

Tor Johnson Records are a music label based in Providence, Rhode Island, who specialize in punk, hardcore and indie metal music.

To promote the release of the new single from the band Aneurysm, “Veronica”, they’re issuing a custom big-hole 45 rpm vinyl record.

What’s so special about the big-hole 45 rpm? It’s a platter with a huge hole in the middle, to fit around a large centre spindle on a record player. These can be seen in jukeboxes from the golden age of rock and roll.

Of course, most modern record players can’t play a big-hole 45 rpm. They’re not designed that way. Which is where 3D printing comes in.

The first 50 pre-orders of the new single from Aneurysm will also receive a 3D printed 45 adapter in the shape of a colorful brain. Get the joke? Think about it for a second, we’ll be here when you get back.

Made in collaboration with HorrorBot Productions, the color pink is shown in the video below, but the label stated on Reddit that other colors will be available too.

Why is Big-Hole 45 RPM necessary?

big-hole 45 RPMAccording to A Journal of Music Things, the reasons behind the big-hole 45 rpm are a complicated mix of nefarious commerce and audio engineering.

Introduced by RCA Victor in 1949, the 45 rpm is a 7-inch fine-grooved vinyl record. Whereas the conventional 33 rpm long-play record promised up to 22 minutes of uninterrupted music per side, RCA devised a different solution by issuing 45s that could be stacked on a tall, fat spindle about 6 inches high.

Once a side of a 45 finished playing after five or six minutes, the tone arm moved away long enough for the next record to drop down onto the platter. The tone arm then swung back into place and the music would continue. With the ability to stack up to ten 45s on the RCA spindle, it was theoretically possible for the music to continue for a full hour without human intervention.

Whilst innovative, the intention by RCA was to crush their rivals, especially those manufacturing long-play vinyl, so they began selling turntables that could only play 45s. The belief was that once someone bought one of these turntables with the fat spindles, they were locked into buying music in that format forever.

But, the Journal continues, there was also a more scientific reason for the larger hole.

When a new 45 dropped from the spindle onto the turntable, it was required to spin up from a dead stop to 45 RPM very quickly. This torque tended to cause the small holes to go out-of-round very quickly, causing record to wobble as it spun. The larger hole allowed the sudden rotational force to be distributed over a longer path — pi x 1.5 = about 4.712 inches — reducing wear and allowing the hole to stay round longer.

Whilst technically surpassed by the CD and digital audio formats, vinyl formats still have their fans. Like Aneurysm and Tor Johnson Records, for example. And if you want to play an old school big-hole 45 RPM on a modern record player, 3D printing provides a neat solution to make that happen.

If pink brains aren’t your thing, though, Thingiverse has some alternative designs for 45 rpm adapters available to download.