Grading Kinds of Grating

Posted on September 15, 2015September 15, 2015 by McCoy

Everyone knows what bridge grating looks like. It’s seemingly part of everything—from stairs to ladders to ramps to fire escapes to flooring. You know this: the stuff that comes in four-foot by eight-foot panels.

Grating is easy to clean (it doesn't get dirty, really), allows light to permeate a space easily, makes a fantastic drain cover, and weighs relatively little for its strength. It's a pretty basic and essential part of construction.

What most people don't consider, though, is its composition. Not all gratings are made of the usual, default-mode steel. Like all matters involving construction, there are very specific trade-offs that need to be made in choosing your material.

Yes, steel gratings are easily the most common: strong, not too heavy, and not too expensive. There's a lot to be said for sticking to the old classics. You know what you're dealing with.

Aluminum is the next most-common material and is usually present in structures that need to minimize weight. These gratings tend to show up in ships and, on occasion, airplanes.

One of the less common materials for grating is fiberglass. (Actually, fiberglass is reinforced plastic, but let’s not get too picky.) Made through a pultrusion process, fiberglass-reinforced plastic grating (or FRP grating) is non-corrodible, unlike steel or aluminum gratings.

This makes the fiberglass type ideal for environments filled with corrosive chemicals or gases; chemical plants are one obvious setting for them, depending on the plant. Another is geothermal generating stations, which tend to have sulfur and other chemical deposits accumulating on everything.

Material isn't everything, either. You need to choose the joints in the grating with care. Welded joints, the most popular, provide both strength and lightness and are good enough for most projects.

Also to consider: the size of the gaps in the grating. If your inventory features lots of small objects, it might make sense to use a heavier grate with much closer meshing. Tends to keep things from falling through.

(I need to invent a personal, portable grating system that I can use whenever I take my house keys and car keys somewhere. Maggie, of course, would just hand me the colander she uses to drain pasta.)

The Lasting Architecture of Vastu Shastra

Posted on September 1, 2015September 1, 2015 by McCoy

Indian architecture has one of the longest histories of any architectural school—or, at least, of any architectural philosophy. It's not like any society really ever stops building for a while, so they all have immensely long architectural histories.

India, however, has an architectural philosophy called Vastu Shastra. Rather than a rigid design philosophy telling you to do this and then do that, it's more a set of guidelines to help with maximizing space, sunlight, and movement within the space, while adding in Hindu and Buddhist beliefs. This all is characterized by square mandalas, which are very distinctive grid-like shapes.

Many of the greatest architectural achievements in human history were designed according to Vastu Shastra. Angkor Wat in Cambodia was designed according to that plan. (Fun fact: the live action version of “The Jungle Book” from the 1960s was partially filmed at Angkor Wat. Great movie.)

One theory holds that they developed Vastu Shastra as far back as 8,000 years ago; many ancient Indian archaeological sites conform to its design principals. It’s been in continual practice ever since, though it was ignored by a lot of architects during the British rule of India. As soon as the British got the boot, though, Vastu Shastra quickly started regaining its popularity.

Part of the reason Vastu Shastra has remained in use for so long is its flexibility. The design matrix allows for adaptation: with new building materials, in more crowded areas, and in non-square spaces. We’ve seen a major resurgence of Vastu Shastra in modern times—among both architects and homeowners in India—and its concepts are spreading all around the world.

Too often, people look at architecture, comment about how exotic it looks, and then just dismiss it as a novelty. People don't build like that, though. There is a philosophy behind every piece of architecture in history.

The End of the VHS Loop

Posted on August 19, 2015August 19, 2015 by McCoy

Maggie had me cleaning out the attic the other day, and I found a cardboard box filled with old VHS tapes. We hadn't used the VCR in something like a decade, but I managed to find it (in the garage, under five or six cans of paint) and hooked it up.

I went through some of our old home videos, and found that some worked perfectly fine and others didn't work at all. There didn't seem to be any real link between their age and how well they worked, either, so I decided to do some research.

There are lots of stories bouncing around the internet about how VHS tapes are supposed to stop working after ten years, or 15, or 20, but there doesn't seem to be any real consensus. People have written their anecdotes about all sorts of lifespans for the dumb things.

It turns out that there are a lot of reasons for the wildly different stories. First off, there was a lot of advertising done when DVDs came out—trying to convince people to switch from VHS to DVD, with the claim that VHS tapes wouldn't last very long.

And the conditions that cause the tapes to wear out vary wildly. VCR malfunction is the quickest cause, of course, but other factors include: rapid temperature swings, frequent use, low humidity, proximity to magnets and electronics, and storage conditions.

What makes it even more confusing is that many of the factors aren't even consistent. Infrequent usage can sometimes cause the tapes to fail, and frequent use can do the same thing.

The last movie released on VHS was “A History of Violence,” in 2006. I doubt that a copy of this will be the last movie ever watched in the format, of course: by that time DVDs had pretty much taken over the whole scene, leaving very little of a VHS market remaining. The “last view” honor will most likely go to someone's home movie, and probably within the next 50 years.

Arecibo: Peering Out

Posted on August 11, 2015August 11, 2015 by McCoy

Built in the early 60s, the Arecibo Observatory in Puerto Rico is the largest radio telescope in the world, with a diameter of a thousand feet. It’s appeared in a James Bond movie, “Contact,” “The X-Files,” and any number of novels.

Arecibo Numerous discoveries have been made from there, ranging from new knowledge about the planets in our own solar systems to the discovery of pulsars, the first planets outside our solar system and examinations of distant galaxies. Basically, I’m trying to say that it’s a really big deal.

Much of the motivation for building the radio telescope was actually military based—it was used to discover Soviet radar installations during the Cold War by, get this: listening for Soviet radar waves bouncing off the moon.

Nonetheless, it has also been one of the most important scientific research installations on Earth for much of its life. One of the most famous programs run out of Arecibo is SETI, or the Search for Extra-Terrestrial Life, which analyzes data from the telescope to try and find any alien radio signals.

You can actually help with that through SETI@Home, a computer program that lets SETI use your computer remotely to help perform calculations. I’ve been running it for years.

In recent times, the observatory has faced significant funding troubles, though it is managing to hold on and continue performing a bunch of worthy scientific work.

If you’re ever in Puerto Rico, you can actually visit the radio telescope. Though you can’t enter the labs or the various work spaces, there is a visitor center that provides a view of the dish, and is filled with interactive displays and exhibits. I went there once; it was definitely worth the trip.

Here’s a fascinating gallery of photos from the construction of the Arecibo radio.

Space Elevators: Going Up?

Posted on July 28, 2015July 28, 2015 by McCoy

When it comes to getting into space, rockets are pretty much staircases at best. More like ladders, really.

Space Elevator

That’s a bizarre thing to say, I know, but hear me out. Rockets are expensive and dangerous, but they’re still the best way we have of getting to space. (There are a couple of other ways, like Orion drives, but given that those things basically ride nuclear explosions…) There’s a theoretical method, that works much, much better: the space elevator. (Hence the staircase joke. Well, I thought it was funny, at least. So I’m not a professional comedian, so sue me.)

A space elevator is, essentially, a long cable—anchored at the equator, extending out into orbit. It works sort of like when you spin while holding a rope, and the rope is suspended above the ground by centrifugal force. (Or is it centripetal? I can never remember.) It’s not quite the same, of course, since it has to have a counterweight at the end, along with several other requirements.

Once the cable is up, cargo and passenger pods would be able to freely move up and down it, at much, much lower costs than rockets. Did I mention how expensive rockets are? Really, really expensive. As in: $10,000 to $25,000 per kilogram they need to lift. (For those of you who don’t have your measurement conversion tables memorized, one kilogram is equal to a bit more than two pounds.)

Carbon Tube

So why aren’t we using them now? Well, because we don’t have a strong enough cable. People keep bringing up carbon nanotubes as an option, but since we don’t have those yet, we just can’t build it.

The space elevator would be more than possible on other, smaller objects in the Solar System. We could build a space elevator on the moon with ordinary Kevlar.

Space elevators aren’t the only ideas for getting to space without rockets. Other ideas are floating out there, ranging from rocket sleds (which does actually involve rockets, but in a much more affordable manner) to skyhooks, which resemble something that a mad scientist, a six year old, and an engineer would design together if asked to create the nuttiest amusement park ride ever, all while hooked to caffeine IV drips.