Tuesday, April 7, 2009

Ski Pulk

So I told you it was coming. My gear sled in all of it's glory, and its associated story. Just look at it schlepping heavy loads across vast frozen distances. This whole thing started at the very place this picture was taken about five years ago, some ideas take longer than others to fully cook up.

My wife to be told me that she had never been winter camping. "What you grew up in Colorado, don't your parents make you survive a week in alpine conditions with nothing but your underwear, britken stocks, and a pack of rice cakes." I guess not. So I decided to take her back country camping and skiing. I have gotten lost in this area enough to know it well, and was comfortable taking her. So armed with my 1.5 seasons of skiing skills and her 1.5 seasons of tele, we hit the back country.

While thinking that this was going to be a gnarly wilderness adventure, I was a little shot down when I saw the well established tracks across the lake and the many people out. I was most impressed by a group of four skiers. They all had the fattest skis and skated across the lake with dazzling speed. They each carried a day pack and one guy dragged a sled, which they would switch off dragging.

A few year later on a hut trip in Colorado, a member of our group had a nice sled which he used to carry his load. OK now I got to try this. So I started construction of my own.

Like any good project research is the first step. I was a bit disappointed with the Internet. I know gear sleds or pulks is a standard piece of equipment for Arctic travel, and from what I have seen those sleds looked professionally built. But I never found a company that made them. I also knew that my hut trip mate's sled was purchased at his local gear shop. Yet no mention of it. The only lead I got was from the Ski Pulk Man from skipulk.com. He sold his homemade sled or any part of it. It seemed well built, but it was pieced together from fancy hardware store parts, and a lot of time and effort. He also has a PDF book that tell you how to make your own. You got to love guys like that who share their knowledge so openly.

From my research and observations there are five main parts of a good gear sled: The sled itself, Fins to help it track, pull poles for control, brake to keep it from pulling you back, and a tie down method.

The Sled- Any toy sled will work. However some are better suited than others. My sled is a local drug store spacial. It was in fact given to me at the seasons end, when a friend of mine was cleaning out her ski lease for the season. The Ski Pulk Man recommends his favorite brand. The ideal sled is wide. This will help with the side hill roll over.

Fins-For the last few years, every time I saw a sled of any type I paid special attention. This included rescue sleds used at ski resorts. If you look at the bottom of these sleds they have large fins or skegs, that run almost the entire length of the sled. Not all gear sleds have them though. The reason being that a gear sled is best used on relatively flat surfaces. A fin helps the sled track on side hills. The fin also adds "noticeable drag" according to Ski Pulk Man. I did not get a chance to compare with and without. An option is to have a retractable fin.

I made mine by simply riveting a 6 inch section of aluminum angle iron. The leading edge was beveled to aide in snow penetration. The sled was pre-drilled for each pop rivet and I used rivet backing (or small well fitting washers) for each.

Since I want this to be an all terrain sled I opted to include fins.

Pull Poles-If a sled was limited to flat terrain poles would not be needed, and cord would have sufficed. However a rigid connection is required to transmit drive input into the sled. It also keeps the sled from running into the driver on the downhills. This is where things can get really fancy. Instead I opted for a very simple cord within 1/2" PVC pipe system. Upon initial test I found that 5' of pipe was just not enough. Five feet because I cut a 10 foot length in two. You need about 6' otherwise your sled hits the back of your skis. So in total I have to buy three 10 foot sections. If you have snow shoes a shorter section will be OK.

I cord I used at first was switched out with webbing. I found the stretch of the cord I was using to be unacceptable.

I spent some working out the attachment for the webbing. Simply drilling holes in the plastic sled and hauling heavy loads through it did not seem like a good idea. So after many trips to the hardware store I came up with this: an eye bolt and two cable clamps. This would distribute the load of each pull location to four holes. The clamps need to be enlarged a bit with a grinder in order to allow the eye bolt shaft to seat correctly.

Brake-I imagined climbing a steep grade while towing the sled, slipping and having the sled drag you down the hill. So I devised an uphill "parking" brake. Of course this is actually pretty standard and I have seen it done before. I had a section of aluminum diamond plate, which I fashioned into a cleat. Then mounted it to a hinge and the hinge to the rear section of the sled. You can see it in the first two pictures. When traveling forward the cleat simply drags over the snow, the hinge allowing it to flow over uneven features in the snow with ease. but when the sled starts to slide backwards, the cleat digs into the snow until it is vertical and acts as a brake. Quite effective. I drilled a hole in the cleat so that I could tie up the brake when traveling on flat surfaces.

Tie down- Even more options exist with securing your cargo to the vessel. Either with bungee cords, or webbing, this is critical. I found this out, not only on my test run, but when I flipped the rig a few times. I found a small dock cleat , which I used to secure my lashing cord. I drilled many hole along the top edges of the sled and fished the cord through. Nothing fancy.
To finsih off the set up I pulled off a hip belt from a pack and secure the webbing to it.
A tip is to load the heavy stuff along the bottom of the sled. This helps keep it from being tippy..

In researching the definition of the word "Pulk" to satisfy the curiosity of a reader, I have come up with this.

A Pulka (Swedish) / Pulk (Norwegian) / Pulkka (Finnish), from Sami language bulke, is a Scandinavian short, low-slung small toboggan used in sport or for transport, pulled by a dog or a skier. The sled can be used to carry supplies such as a tent or food, or transport a child or other person. In Norway, pulks are often used by families with small children on skiing trips (small children being pulled by the parents).

It was not easy to find an answer since "pulk" was not defined in a standard english dictionary.

I also found another site http://picearubens.tripod.com/Pulks.htm. This has a few more links to commercial gear sleds.

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