The P&A Shop

A typically messy electronics bench
The electronics bench

Welcome to Olin Science 181, the Physics & Astronomy department’s machine shop. As the department’s support team, we regularly discover, design, and build all sorts of curiosities. This blog is just a small sample of the fascinating things we come across every day.

They’re interesting. Sometimes strange. Sometimes oddly charming.

Always worth sharing.

Cicadas

Cicada and molted shell on a leaf.
Very chill bug.

While exploring a potential site for measurement equipment, it’s important to keep an eye on the local wildlife. After a long time underground, those big red eyes are just taking it all in.

Not pictured: all of the other cicadas all over the place. Because where there’s one, there are bound to be many, many more. Brood XIV, maybe?

Alligator Clip

An alligator clip taped to a steel rod.
Fierce fellow!

Sometimes you stumble across a delightful artifact. One with an unknown, perhaps unknowable history. Clearly, at one point, it was necessary to hold an object in a particular place, and none of the available clips, clamps, or clasps were up to the task.

A steel rod, an alligator clip, and some electrical tape to the rescue!

What’s fascinating about this isn’t the specifics of the object, but the way that these temporary, stopgap solutions can linger. After enough time and use, they become ordinary and unremarkable. Familiar.

Until, some indefinite period of years later, a fresh set of eyes spots them in an old drawer. Look at what’s in here!

Optical Discs

Stack of DVD-R discs.
Never used, never to be used.

It really wasn’t that long ago that computers came equipped with optical disc drives, and they were effective means of data storage, and the density you could store on a DVD instead of a CD was pretty exciting. Now? They’re not only borderline-useless, but the features that we used to reference as a cultural touchstone are no longer obvious to our students.

It’s not that they don’t know what these are. It’s that they haven’t handled a million of them to know their dimensions, to understand the diffraction rainbow they make. The physicists around here remember using the inescapable AOL discs as cheap, readily available diffraction gratings back in grad school. The astronomers use their proportions to illustrate the shape of the Milky Way Galaxy. Students now need to physically hold one of these to get the idea, because they don’t have a mental image ready to go.

Our Galaxy, if you were wondering, is roughly proportioned as a CD, only instead of being a millimeter and a half thick, is more like 1,000 light years. Very roughly, anyway.

Carbonized

Bamboo cutting board with large spiral section burnt to charcoal
Oops!

Strange things come through the shop doors some days. This one perfumed the shop for a time, a bamboo cutting board which had been resting on a hot electric coil. Everything smelled like burnt corn husk.

Everything. It was a pervasive scent, intriguing at first and overwhelming after a time.

Bamboo cutting board with a smooth, round divot where the burnt area had been
Looks and smells better.

Scraped, chiseled, sanded, and… well, not exactly like brand new, but in usable shape once again!

Blue Dot

Use blue dots for sure shots!

These are not flashbulbs, merely incandescent A-lamps, but check out the sweet vintage ad!

So the “blue dot” thing was a quality indicator that Sylvania used in their classic flashbulbs. A magnesium filament inside an oxygen environment within the bulb produced a bright flash of light, assuming the envelope hadn’t been compromised. A dot of anhydrous cobalt (II) chloride inside that zero-moisture bulb would remain blue. If there was a leak, atmospheric moisture would react with the cobalt chloride to turn it pink, an indicator that this bulb might not work.

What’s less clear is how, exactly, one wee flashbulb is going to effectively illuminate that whale – flash photography being not super effective at distance – but whatever.

Apollo 13

News release announcing the upcoming Apollo 11 launch in 1970.
We all saw the movie, right?

Fifty-five years ago saw the launch of the Apollo 13 lunar mission, on 11 April 1970. It didn’t go to plan, of course. Things took a bad turn, could have been worse, but who can blame them for optimism in the weeks leading up to it all? Moon science is cool!

Check out that pure 1970 map illustration!

Maps, plans, a pretty tight itinerary. It’s expensive and difficult to go to the Moon, so you don’t waste time. But don’t those hand-drawn maps just make it so inviting? Presumably the astronauts carried maps which were much more detailed and useful, if less likely to get the kid inside all of us super-excited.

Apollo 14 would reach the Fra Mauro highlands in early 1971, though Lovell, Swigert, and Haise never flew into space again.