A good week for tube

August 27, 2009
By: Eric Lundin

It was a good week for tube, at least as far as I am concerned. I am always on the lookout for any chance to get out of the office and see tube or pipe applications, and I had two such opportunities this week.

First off, the local elementary school needed a new play area. The old one was sprawling, beautiful, and in great shape despite its age. It had slides, ladders, rings, ramps, stairs, towers, pathways, swings, and on and on. It had been built long before the Lundin family moved to the area, so it was a prominent feature, or perhaps THE prominent feature, that my children remember about the elementary school.

My kids and I spent hundreds of hours there weekends, summer evenings, weeknights after school running around, exploring, hiding and seeking, and for the most part, playing tag. Everything was scaled down to child size, so I'd often get tangled up in a narrow stairway or slow down too much to negotiate a 90-degree turn, and they'd get away from me. It was more a game of "chase" than "tag" because little tagging transpired.

It had a couple of drawbacks. The fact that it was good for hide-and-seek meant that it was good for hiding and not being found, and judging by the quantities of beer bottles and cigarette butts that magically appeared on the ground many mornings, some not-quite-drinking-age sorts had this figured out. Another was that it was made from wood, and wood leads to splinters. It had a few other drawbacks, too, so the school district decided to replace it.

With what? I am glad you asked. A new structure ... one made from a certain material that has to be painted to prevent rust ... formed into components that don't require too much hardware, but rely on slip fits and just a few fasteners ... yeah, that's right, steel tube. I volunteered to help with the assembly, and it was time well spent. My intent was to repay the community for the many hours of enjoyment my kids and I got from the previous structure; the fact that I spent part of the weekend assembling tubular components was the icing on the cake.

I looked at the workmanship a bit, checked out the welds, noticed some areas where the paint didn't cover well, but somehow managed to refrain from discussing my job. I figured I'd end up working alone if I started rambling too much about the many intricacies of tube and pipe. You know, I am pretty certain that most laymen can't comprehend everything manufacturers do for them. Besides, I didn't want people to think I was some kind of nut. Having said all that, I can appreciate everything that goes into making and fabricating tube, and I am 100 percent sure that it makes a better play structure than wood does.

A few days later I took my youngest son out to shop for a bicycle. He's 14 years old so I figured he needed good advice and something durable, so I ruled out any stores with names that ended in "mart." We went to an actual, bona fide bike shop, the same one where my dad took a nearly-7-year-old Eric to shop for a birthday present a few decades ago.

It didn't take long to home in on a Boulder SE, made by Giant. Twenty-one speeds, Shimano shifters, double-wall rims, front shock absorbers, a contoured seat, advanced geometry, and judging by how smooth and quiet it is, the best bearings money can buy.

And then there's the frame. A 6000-series aluminum! Of course I commented on the welds' appearance, the shape of the cross section, the geometry, and the weight. I figured I could get away with it in a bike shop. Hey, the staff is made up of avid cyclists who know their products and I think they were more than a little amused by my enthusiasm. I guess it's not every day that a customer gets excited over frame construction and strikes up a conversation about metallurgy.

It turns out that Giant actually uses two proprietary alloys for many of its frames, alloys it calls AluxX and AluxX SL. Both are based on 6013. The 6000 series is aluminum combined with magnesium and silicon; 6013 has a bit of copper added. I checked the Web site of the aluminum authority, Alcoa, and found that it refers to 6013 as an aerospace alloy. Giant noticed that it makes a great bicycle frame too.

Using a material with a favorable strength-to-weight ratio, along with a drawing process that varies the wall so it's thick where the stresses are greatest and thin everywhere else, allows Giant to keep the weight off. Its road bike frames weigh in at 2.3 lbs. and its mountain bike frames are 3.1 lbs. Giant explains all this in more detail with text and a video.

Of course, I pointed out to my son that I get a better workout on my old, clunky, steel-framed bicycle because it's heavier and takes more effort to propel. He smiled his patient smile, the one he uses when he knows he has the upper hand. Then he summed up all of his bike's features in just three words.

"Mine is faster!"
Eric Lundin

Eric Lundin

FMA Communications Inc.
2135 Point Blvd
Elgin, IL 60123
Phone: 815-227-8262