Monday, April 25, 2011

Obligatory Duct Tape origins sidebar

I recently posted a blog entry on my negative experiences with duct tape, using it as an analogy for work, where the quick patch seems expeditious but in the long run leads to more rework or lower quality. But from whence doth come this ubiquitous duct tape, and how didst it earn its appellation?

Well, a little research shows that the product we now call duct tape originated during that great mother of invention, World War II. Permacell, a division of Johnson & Johnson, started with a cloth based medical tape, added a new super-sticky rubber based adhesive, and then laminated it with a coating of polyethylene. The result was a strong, flexible, durable, (almost) waterproof tape that could be torn into strips or other convenient sizes. Soldiers used it to seal ammunition boxes and make field repairs to equipment, including guns, jeeps - even aircraft. Returning GI's were enamored with the stuff and bought it from military surplus for civilian uses, including sealing ducts. Manufacturers started making it available commercially in the now familiar metallic color rather than military olive green.

It was not called duct tape during the war, however ... so how did that name enter the common vernacular? There are a couple of possible explanations, and they probably all played a factor. The most obvious derivation would be from popular use of the product to seal metallic ducts. (Standard duct tape is actually no longer acceptable for this purpose according to most state building codes; there is special purpose stuff that holds up better.)

Another common name for the stuff is duck tape. Cotton duck is a type of canvas, and duck tape is an old fashioned name for strips of material. Hence this new fabric backed tape would have fit the generic term. Now combine that with the story that soldiers referred to the stuff as duck tape due to its ability to shed water. One enterprising company (Manco) jumped on that bandwagon by creating Duck Brand Duct Tape, with a duck on the logo. They continue to manufacture a variety of forms of the iconic product today, sponsoring contests and promoting creative uses for it.

So, which came first, duct or duck? Is one name a homophonic bastardization of the other, or did they evolve in parallel? Where's MacGyver when you need him.

Tuesday, April 19, 2011

Real Engineers Don't Use Duct Tape

I have a love/hate relationship with duct tape. It's like that bottle of Peach Schnapps that resulted in one too many hangovers, or the hot date who borrows your car and returns it with an empty gas tank and a new dent. Enticing at the time, but you generally regret the encounter.

Wait a minute - an engineer disparaging duct tape? What would MacGyver say? You know MacGyver, that American TV show from the 80's? An agent with some nebulous secret government agency, he chose to solve problems with his wits and extensive scientific knowledge rather than with guns. Each episode featured him concocting a way out of a tricky situation using the materials at hand - which generally included his Swiss Army knife, a paper clip, and duct tape. He was a rock star among engineers; we all have a little MacGyver in us. (The Principles and Practices portion of the Professional Engineers exam really ought to have a section that begins "solve the following problem using the contents of your pockets and materials found in this room.")

So what's the problem with duct tape? I'll tell you what. Duct tape is a patch. A kludge. A temporary fix until a real repair can be accomplished. It's great for the field. You really ought to carry some in your car, or when you go camping. It might be just the thing to patch a hole in a tent or keep an auto part from falling off until you get home or to a repair shop.

What you generally can't do with duct tape, however, is actually repair something. Despite its metallic backing, cloth reinforcement, extra sticky glue, and water resistance, duct tape will eventually fray, tear, curl at the edges, slip, and leave behind sticky residue. Heck, current building code does not even allow it to be used on ducts! I can think of many times I have made a "repair" with duct tape, only to regret it later, when the "repaired" object is again failing, but now covered with unsightly peeling sticky dirty silver tape. I would have been better served to reach for the tools and supplies to make an actual repair, or replace the item, as I had to do eventually.

Consider MacGyver. When trapped in an unfriendly country with a wounded scientist, he might scrounge together a lawnmower, ladder, and parachute - with a whole lot of duct tape - to build an ultralight and fly them both across the border. But the next day do you think he says to his wife "Hey honey, let's take the kids for a ride in the ultralight, maybe stop for some ice cream." No, that thing probably fell apart when he landed!

So what's my point?

Engineers design and build; we test and fix. Sometimes we patch or hack. But it's important we make that decision - fix or patch - consciously, intelligently, and ethically. When that hack becomes part of the process, when that debugging kludge gets labeled a fix - are we trading future viability for present expediency? Are we compromising quality? Are we building products with duct tape?

So next time, think twice before you reach for that duct tape.