Sled Building Boo-Boos

“Make dogsled runners out of aluminum? Ha! Leonard Seppala tried that with surplus aircraft parts 40 years ago and the sled broke into pieces…” So said Cindy Molburg.

Cindy Molburg was the editor of Team and Trail, the one and only international mushing magazine for many decades. When a story was not covered in T&T the doubters would say it never happened. She had seen everything and knew everybody in the sport. But if someone, no matter what their reputation and record, even a legendary musher like Seppala, wants to build a proven wood sled design with substituted aluminum or fiber reinforced plastic parts, the outcome will usually be disappointing.

Two years ago I took pictures in Thunder Bay, Ontario, showing a team of sled dogs being loaded into a Douglas DC -3 for a charter flight to Greenland.

I remember flying with my family across the Alps from Rome to Zurich in a DC-3, probably around 1958. The flight attendants were  busy after take-off and before landing passing out candy and gum to chew as a way to relieve the pressure in our ears from the altitude changes. These aircraft were not pressurized like more recent airplanes expected to cruise at 10,000 meters or higher..

About the DC-3 shown in the picture, it has modern retro-fitted turboprop engines but otherwise the flaps are still fabric and the airframe is likely 60-70 years old. Old in airplane life  years but there has never been a DC-3 crash caused by structural failure.

My point is, if Seppala had known  a few things about building with aluminum like the engineers at Douglas Aircraft, his sled would still be flying 60 years later like the DC-3.

When I interviewed for a job at Boeing in 1969, the recruiter hired me with a degree in Engineering and Applied Science, a liberal arts type of engineering, not the typical engineering accredited program, and only one class in structural engineering. (We were discouraged from taking courses that were too practical, those were called “cement mixing.”) He said, all you need to know is MC/I and P/A, (the two basic formulas for calculating stress in bending or compression and tension.) That turned out to be true, because at the new hire level as a stress engineer, that was all I did need, and the more advanced concepts like fatigue strength were applied by veterans with the company, and the design principles like geometry, specifying structural elements and their dimensions, rivet head shapes and holes, stress raisers and notch sensitivity, etc. were the responsibility of a different group called project engineers with their accumulated experience going back to the Wright brothers. The overriding principle of least weight, optimum life performance design was called “one hoss shay” from a poem by Oliver Wendell Holmes written more than a hundred years before. About that another time.

Do you ever notice the flex of the wings on large modern aircraft in turbulence? Do we still fly wooden airplanes and use wooden skis? Progress comes from adapting designs to use new and better materials.

The structural and design properties of aluminum extrusions and rolled bars are very different from wood. If you try to use a solid aluminum part with the same dimensions as wood you run up hard against the greater density of aluminum. With hollow and roll-formed profile shapes you can take advantage of aluminum by specifying different cross sections, provided you know what you want.

Using aluminum to match the stiffness, weight and breaking strength of wooden runners, that would be a waste of the material. Less weight and greater breaking strength are usually better, although in a range of similar shapes there is a trade-off between the two; what about stiffness?

What you expect for stiffness in a sled runner may be conditioned by the past limitations of wooden runners. Remember the Noodle Sled? That was a design from the early 90’s with plastic and aluminum parts that made it ultra-flexible… Joe Runyan said it  was great on trials with moguls; maybe he has a photo. Or maybe I do somewhere in the archives.

With stiffness there is a presumption of greater breaking strength within a range of similar shapes: thicker will be stiffer and have greater breaking strength. In general the presumption is false; it does not follow that stiffer is always stronger. Twice as stiff could be half as strong. A stiffer cross section can have lower breaking strength and, for other reasons as well, may not be stronger in practice if you run into a tree or hook a stanchion on a truck bumper.

You can calculate breaking strength for any material and shape combination, and there is a defined standard testing procedure to verify your computation, but it is a proxy, just like the proxies used in scientific/nutrition studies. Flexibility is a virtue with benefits in mechanical properties as much as it is in biological systems and behavior. An elastic part may be able to “shed” and redistribute or absorb a shock or impact better. “Something’s gotta give.” That is what I told a musher who complained her sled “only bumped into a railroad trestle.”


Microsoft Works.

An excitable Lithuanian.

Steering a dogsled.

For stand-up comedians, one well-worn oxymoron is “military intelligence.”

A few more of the European national stereotypes variety:

English gourmet foods

German politeness

Italian/French government

I was thinking only of Italian government as an illustrative example when I suddenly remembered the famous saying of Charles de Gaulle, “How can you govern a  country with 246 varieties of cheese?”

If I stepped on your toes with some of these, I intended to. Overall, any typical list of representative oxymora leads to the conclusion that like beauty, it’s in the eye of the beholder.

Why is steering a dogsled an oxymoron?

How’s that working out for you? Where did you expect the sled to go? The dogs are going one way; would you like the sled to steer in a different direction?

The best steering and handling sled should follow the dogs with the least effort from the driver.  A sled that needs to be steered, even if it responds very well, is a big pain in the ass.

Take a Danler Sled or similar Euro design… Please!

(“Take my wife… please” was a line from comedian Henny Yongman, one of the popular performers of that era on the Borscht Belt circuit, the Jewish Alps or Catskill Mountain resorts north of New York City. The first time I heard the term Jewish Alps I was making my way to subway station in New York to get to the Grand Central train station with a stack of wooden cross country skis on my shoulder around 1968 during a heavy snowfall that paralyzed the streets. A man called out in heavy accent, “Where ya tink ya go, da Jewish Alps?”)

Take my Danler sled… please. UNFORTUNATELY it handles just like skiing, and steering a sled cannot be the same as skiing.

In skiing you put your weight on the downhill (for a side hill) or outside (for a turn) ski, bring the uphill or inside ski in next to it, and lean into the hill or into a turn. But the skis/runners of a sled are not movable. If you do lean into a turn you are putting your weight on the inside runner and often over-steering.

Mushers might notice that a dog team behaves in cornering like a long wheelbase car or truck with the rear end or dogs cutting the corner closer than the front end. Combine that with the over-steering sled… on a tight turn with a very responsive skiing-like sled, the musher has the choice to lean in, cutting the corner too close and possibly hitting the tree, fence, sign, or other obstacle ahead in or beside the trail; or lean out, off balance, to risk being thrown off the sled. Icy trails can be frightening for similar reasons.

Turnabout is fair play, so the saying goes: Man Bites Dog, Noodle Eats Danler! The Noodle Sled was an ultra-flexible sled built with plastic and aluminum in the early 1990s. Joe Runyan used one for several years; he says they were great on mogul trails. Does anyone have photos?

Some sled builders and mushers came to the conclusion that the so-called sled steering systems using lines and pulleys attaching the bridle to the driving bow, pulling the bridle to one side or the other as you move the driving bow, although ingenious and elegant engineering, are overkill. Notwithstanding, ingenious features can always serve a purpose in sales and marketing to justify a higher price.

The exception where this type of amplified steering can be helpful is the freight or tourist transport sled, where the heavy load makes ordinary sleds unresponsive. The first big toboggan sleds that I built around 40 years ago had an  8 foot (250 cm) long plastic toboggan bed but the tail of the runners was barely long enough to stand on, an advantage for steering and handling. These sleds could be steered like a canoe, by moving the rear of the sled sideways to point in the direction you wanted to go.

Long ago basket style freight sleds were steered from the front with a “gee pole” that gave leverage to the driver who either ran along in front of the sled behind the wheel dogs or rode a “ouija board” in the same position. Now my mind is groping for a memory of something Ross Saunderson did in the North American Championships… was it a kind of mini-sled between the tails of the runners to stand on at the road crossings so the plastic on the sled runners would not get roughed up?

Another issue, though not so much about steering, is the optimum width of the runners or skis. If you believe cross country skis are comparable to dogsled runners, remember that for sliding and load bearing, in XC skiing your weight is usually on one or the other and not on both. So the  equivalent load bearing sled runner would be half the width of a ski, not the same width.

With mid and long distance mushers, the other problem is that an overly steerable and responsive sled on a typical uneven, rough, or winding trail requires constant attention for hours. If you end up with a sore neck and shoulders at the end of the day, blame your sled.

Later another aspect of “something’s gotta give,” the interplay between steering, bridle design, and crash-worthiness.

Have Your Cake And Eat It Too

But eat it all at once, then go hungry for the rest of the day.

More evidence that how long you go between meals is a positive factor in health.

Title: Time restricted feeding without reducing caloric intake prevents metabolic diseases in mice fed a high fat diet
Authors: Megumi Hatori, Christopher Vollmers, Amir Zarrinpar, Luciano DiTacchio, Eric A. Bushong, Shubhroz Gill, Mathias Leblanc, Amandine Chaix, Matthew Joens, James A. J. Fitzpatrick, Mark H. Ellisman, Satchidananda Panda

Salk study may offer drug-free intervention to prevent obesity and diabetes

Extended daily fasting overrides harmful effects of a high-fat diet

May 17, 2012

LA JOLLA, CA—It turns out that when we eat may be as important as what we eat. Scientists at the Salk Institute for Biological Studies have found that regular eating times and extending the daily fasting period may override the adverse health effects of a high-fat diet and prevent obesity, diabetes and liver disease in mice.

In a paper published May 17 in Cell Metabolism, scientists from Salk’s Regulatory Biology Laboratory reported that mice limited to eating during an 8-hour period are healthier than mice that eat freely throughout the day, regardless of the quality and content of their diet. The study sought to determine whether obesity and metabolic diseases result from a high-fat diet or from disruption of metabolic cycles.

“It’s a dogma that a high-fat diet leads to obesity and that we should eat frequently when we are awake,” saysSatchidananda Panda, an associate professor in the Regulatory Biology Laboratory and senior author of the paper. “Our findings, however, suggest that regular eating times and fasting for a significant number of hours a day might be beneficial to our health.”

More specifics for daily fasting here:
Regarding meal or snack intervals for racing sled dogs:
Gary Paulson had the notion that dogs would run better with more energy if they snack frequently and regularly relatively small amts, just the same as Tour de France bike racers, though not the same snack ingredients. I agreed with him when he first talked to me about it; I had discovered that even in a two hour race like The Pas my dogs were more competitive if I stopped for the three minutes +/- to give them a quick snack. I experimented with fish, ice cubes containing liver and other ingredients, what I called pupsicles. I would make up the downtime in The Pas within 15-20 minutes usually. Sometimes sooner than that. Unanswered questions whether it was energy from the food calories (unlikely) water for hydration and/or psychological stress reduction.Bob Fritz’ Peak Performance powder seemed to address many of those mechanisms. Gary thought that each dog had an optimum snack interval so that the musher had to determine the lowest common denominator of the team or the short interval dogs would fail. Typically 50 minutes to an hour and a half, maybe more for slower pace according to the type of race.
Stress is like a lever, and current physiological and mental state, the terrain, establish the position of the fulcrum for better and worse, determining how much functional advantage or disadvantage stress has in the final result. Eustress is the level of stress that stimulates growth and health. Distress is excess stress with net harmful effects. The factor determining whether stress is good or bad may often be the mental state of the subject at the outset of the trial. For example, tell a person to run 100 yards in cold weather at their fastest speed. Or, tell them that their mother sitting in her car 100 yards away has a bomb in her lap that is going to explode if her son or daughter does not get their in time or similar circumstances and that same distance run could very well cause an asthma attack. Similarly I found that would happen to me if I lost my team and started chasing after it. I would need to suppress my anxiety…
Bob Fritz told me about the book Why Zebras Don’t Get Ulcers  many years ago. He also developed a sports supplement for dogs, Peak Performance that supported eustress vs. distress. The action of the sports supplement HMB illustrates the paradigm of distress>hypoglycemia>elevated catabolic hormones such as glucagon overriding normal metabolism, tearing apart muscle proteins for fast energy despite adequate energy in existing fat stores. For most athletes then and now the presence of lactate in Peak Performance was counter-intuitive or paradoxical. But Bob Fritz mentor George Brooks established the Lactate Shuttle and perhaps the name years before.

A Disingenuous Musher

Cacique is dead…

It was a terrible moment for the two friends who loved their Siberian Huskies so deeply. Gustavo called to Juan Pablo when his team came by. The beautiful orange colored dog with blue eyes was lifeless on the snow. Already before the race they had been anxious about the water they could hear running under the ice along the trail. What if the ice collapsed, dropping their dogs into the water? The warm weather, hot sun on the frozen beaver ponds and open trail between the scattered lengas and robles trees in the forest, and the excitement of the race had caused this tragedy. The two Argentinos could not accept that this happened.

Tony’s team came next. Cacique is dead, they cried out. What do you want me to do about it? He did not stop. Come on Charlotte he told his leader. Run, run, my babies. Juan Pablo helped load Cacique in Gustavo’s sled. They started on, but it was not the same race they began only fifteen minutes before.

I was already arrived at the restaurant Las Cottorras for half an hour when I heard the excitement. Gustavo would not cross the line until Juan Pablo came alongside, then the two could finish together. His friends were yelling at him and urging him ahead. Go! Adelante! The finish line is in front of you.

The two friends linked arms as their teams crossed under the arrival arch. TV cameramen from Buenos Aires and Paris recorded the moment. The sleds collided in the narrow space between the poles supporting the arch. Gustavo’s sled dumped to one side, Juan Pablo’s to the other. The dead dog was thrown out on the ground. Cacique jumped up and attacked one of his teammates.

I was giving my dogs another serving of water with a little food mixed in. It had been hot in the sun; it was still warm in the snow and shade among the trees beside the restaurant. In a corral within a few feet of the dogs, beef cattle were chewing on hay. We could smell the green hay and the lamb roasting at the fire pit on the other side of the restaurant. Gustavo and Juan Pablo’s teams were still in harness. The two drivers had their arms around each other, faces wet with tears. As friends came over, they would share in their grief, sobbing and hugging one another.

I sat on the stump watching my own dogs resting comfortably; they were only slightly interested in the commotion around them. Finally I decided to help the dogs from Gustavo’s team that were tangled in their lines. To keep them apart and settle them I gave them water with a sprinkle of food in the bowls I used for my dogs. When I came to Cacique, the last dog, he growled and tried to bite me. I liked you better dead, I was thinking. I went back to sit on the stump beside my team.

Take this away! The veterinarian from Cargill Doggie dog food company was saying to Gustavo. Don’t you know that will kill the dogs with stomach torsion? Water, food, after running is not safe for one hour. I was glad that Gustavo had recovered from grief enough to remember his dogs. Now I pretended not to be associated with the crime of watering dogs after a race. When the veterinarian’s girl friend came by I asked her in French what was going on. Why were Gustavo and Juan Pablo so unhappy? After all, the dog was not dead. It was Tony, she said in her Spanish French, pronouncing all the last consonants. He hurt them badly when he would not stop. They thought he was their unconditional friend in this beautiful sport. It was a shock to them. What about the water for the dogs, I asked, I do it when the weather is hot or cold. I think the veterinarian does not have as much experience with sled dogs in this subject. The next day Elena recounted that the girl friend had told the veterinarian that I said he was “incompetente.”

Don’t let any dogs loose. They might chase the cattle and injure them! The restaurant owner was worried about the wolf-like dogs in his yard. These Herefords looked rather like range cattle to me. I remembered the time Don Montgomery stopped in Edmonton to buy meat, driving his dog truck up to Alaska. This was a place that slaughtered horses. Don was both a musher and a horse breeder from Ohio, closer to Kentucky than to Alaska, immensely proud of his colt out of Secretariat . One dog charged into the corral with horses. Don ran into the office to tell them a dog was loose attacking the horses. They laughed. It was not a fair match for the dog. The first horse kicked the dog in the head and almost killed him. Some of the horses had been raised and sold by outfitters along the Alaska Highway. Those horses knew wolves and they knew what to do about that. Another time in Argentina one of the ponies tried to reclaim and eat the hay we had used for bedding the dogs. This horse was winning against the “dogs in the manger” until Monique and I ran him off.

(By the way, stomach torsion is more likely a result of what happens after feeding or watering, not directly caused by when you do it. Many sled dogs are snacked or watered on the trail and then take off immediately. When I asked him about the “dangers” of watering dogs, Doc Lombard told me that because of the hot weather where he lived near Boston, Massachusetts, and the need to stay close to home during the week on into the Autumn when mushers in other locations could be doing serious training, he could not run  his dogs very far. But as a minimum to keep them in shape he would hook up teams of dogs, run them out a mile. give them a pint (400 ml) of water and then run them back to the kennel. My impression is that stomach torsion in athletic dogs is more likely a result of some extraordinary excitement after feeding a big meal, not a snack or moderate amount of water.)

A Disingenuous Tourist

At the Sudbahnhoff in Vienna at 4:30 in the morning I was thinking about life. Or was I just confused, and. unable to focus on any logical idea or plan how to spend the next 4 hours, mistook those thoughts for the fog of philosophy? There were people sleeping on the benches, sitting up and lying in awkward positions, or wandering around with no more purpose than I had. In the blue and green light the impression was more like a zombie movie or could be a vampire movie except that I was returning from a trip to Transylvania, which beautiful mountain scene had nothing eerie about it.

Isn’t travel a metaphor of life? Some of the people sleeping on the floor were well dressed, temporarily stranded out of their usual element. Joseph Conrad admonished his readers in Lord Jim “swim in the element that surrounds you.” Did Joseph Conrad swim in this element, the same train station I was in now?

The ticket counter was shuttered where I stood for half an hour in line to buy a ticket to Miercurea Ciuk in Transylvania which turned out to be better known by the Hungarian name and for which there was no train. The ghost of that day was there for me; another traveler would see the ghosts of the second world war or the Austro-Hungarian Empire, or The Sound of Music. or Sigmund Freud.

Does the Austrian government pay people to be bums and stranded businessmen, subsidizing them with clothes or money like they pay people to farm as a way to preserve the national image and cultural heritage? What would Austria be if the Alpine meadows were not populated during the summertime with cows bobbing their heads to the music of bells tinkling?

Ingenious and ingenuous are two quite distinct words though they might have common parents in Latin or Greek. You know what an ingenue is? Think ingenue Not. There is a movie with the title, The Accidental Tourist. I didn’t like the film. The idea of being a tourist of any kind within the common meaning of the word, accidental or deliberate, only reminds me of being a bored tourist or going back to school to be led by authorities and teachers. Except for job interviews, or maybe except for structured formal situations… or maybe can be said this way: when meeting people, observing and studying them it’s better they think you ignorant and unexceptional, the empty boat referred to by the Chinese statesman. As George W. Bush said, “they misunderestimated me.” But in his mouth it came out as bragging.