Can You Help 3D Print A Selectric Ball?

The IBM Selectric changed typewriters as we knew them. Their distinctive ball element replaced the clunky row of typebars and made most people faster typists. When [Steve Malikoff] thought about 3D printing a type ball — colloquially known as a golf ball — it seemed like a great idea.

The problem? It just doesn’t work very well. According to [Steve], it is likely because of the low resolution of the printer. However, it isn’t clear the latitudes of the characters are correct. and there are a few other issues. It is possible that a resin printer would do better and there’s a call for someone out there to try it and report back. We are guessing a finer nozzle and very low layer height might help on an FDM printer.

Judging from the images, it looks like some of the balls do pretty well, but don’t get a full strike at the tilt angle. So it could be something else. However, it does sound like cleaning up the print so it fits is a major problem.

The Selectric was notable for several reasons — you can see an ad for the machine in the video below. The type ball meant you couldn’t jam keys. Since you didn’t have to unjam keys and you had the ribbon in a cartridge, you would have to work really hard to get ink on your fingers, even if you used the cloth ribbon instead of the arguably better carbon film ribbon. The Selectric II could even use a special tape to lift the carbon ribbon off the paper for correcting mistakes. No white-out liquid or fussing with little strips of correction paper. The fact that the ball moves means you don’t have to clear space on the side of the machine for the platen to travel back and forth.

Can you help? If you have a Selectric I or II and a high-quality printer, this would be a fun project to try and report back your results to [Steve]. If you are familiar with the later issue typeballs, you might not have seen the wire clip that [Steve] uses to hold the ball in place. However, you can see them in the video ad below. More modern balls use a plastic lever that acts as a handle so even with cloth ribbons you have less chance of getting ink on your hands.

Although there were Selectrics meant to interface with a computer, you can refit any of them to do it with some work. The Selectric also has a role in one of the great techno spy stories of all time: The GUNMAN project.

Continue reading “Can You Help 3D Print A Selectric Ball?”

Scale Model Of A Civil War Mortar Shoots Steel Golf Balls

[Sir Keyboard Commando] just emerged from his machine shop to show off the 1/6th scale model of a Civil War mortar which he recently finished fabricating. It started with some bar stock that measured four inches in diameter and accepts steel balls the size of golf balls as ammunition.

The bore diameter is 1.725″ which gives just a bit of clearance for the 1.685″ golf ball specs. Each of the steel balls weighs in at just over 11 ounces. You get a really good look at the finished mortar in this test-fire video. It’s quite small but [Sir Keyboard Commando] reports that the full assembled unit still weighs in at a whopping forty pounds.

This certainly isn’t an improvised weapon, but we’re quite surprised to see it being test fired. We’d bet it turns some heads that the local firing range.

[via Reddit]

Fully-automated Golf Ball Gun

If you get in the line of fire this golf ball launcher is gonna leave a mark, or worse. It’s based on the same premise as the sausage gun, but now everything is automated and no meat products are used.

A hopper stores a row of golf balls. When it comes time to load, a ball falls into the chamber, starter fuel is sprayed into the combustion area with the aid of a fan, and after both chambers are sealed the propellant is ignited.

We’ve embedded two videos below for your amusement. It looks like [Chrille] and his friends are being careful with their creation. We’re glad for that because this is about as dangerous as the high-velocity ping-pong ball launcher. Continue reading “Fully-automated Golf Ball Gun”