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ViewsRaftingFrom Alaska Outdoors Wiki
[edit] IntroductionRafts are a popular mechanism for accessing Alaska's waterways as they can easily be transported into remote areas by aircraft, and because of their stability and relatively large cargo capacity. Rafting has been a growing recreational sport throughout the world, and Alaska is no exception. However, we have more reasons than most for wanting to explore our great land with these wonderful devices. Alaska has more raftable rivers, creeks and streams than any other state, with far more diversity of scenery, from mountain glaciers to wide open expanses. Alaskans use rafts for float hunting, fishing, mining, exploring, whitewater thrills and for peaceful solitude. Rafts can be deflated and delivered to remote Alaska areas in airplanes, trains, automobiles and power boats. [edit] Raft Considerations for Alaska WatersRaft types: While there are many one of a kind inflatable boats that are used for rafting there are two primary types of craft commonly used for rafting Alaska rivers; round boats and catarafts. Round Rafts: The invention of round inflatable rafts for whitewater floating are generally credited to American GI’s, who, after WWII, bought up surplus military bridge floatation rafts and employed them in the pursuit of fun. In recent decades material has increased durability and reduced weight, while things like self bailing floors have made the rafter’s life considerably easier. Round boats are generally about twice as long as they are wide. Some are narrower so that they can fit through tighter places on small streams, but as they get narrower they also get less stable. So if you broach sideways on a mid-stream rock you might appreciate a wider craft. Round boats can be purchased as a tub floor boat, with a single layer of waterproof fabric for a floor. Or you can buy one with a self bailing floor that is like having a stiff air mattress to walk on. The advantage of the self bailer is that any water that gets splashed into the boat will quickly drain out the holes along edges of the floor. They are also easier to walk around on than a tub floor, and can carry heavier loads. The disadvantages are increased cost and weight. A raft’s weight capacity is determined by the length and width of the boat at the waterline, as well as the diameter of the inflatable tubes. Generally, for mild rivers, you cannot easily overload a raft. There isn’t enough room to put that much stuff in them. However, if you pile it high enough you can over do it. The waterline length is a product of the boat length, less the area used for the kick (upturn) of the ends of the boat. The rise of the kick is needed to lift the boat over waves instead of crashing through them. Some boats have less kick, or even no kick, and while this can add to the weight capacity, it will reduce comfort and safety in rough water, and make turning slower. In their simplest form a raft can be powered and controlled by several people with paddles sitting on the inflatable tubes along side the boat. With enough determined paddlers this can be sufficient for even the wildest rivers. However for increased control a frame and set of oars can be added. Generally a good oarsman can do about as much work in moving the boat as four good paddlers. Oars are more efficient and time is not lost communicating instructions to the other paddlers. Comfortable seats can be added to the frame but they are not necessary. Passengers can sit on inflatable thwarts (cross members in the middle of the boat) or the sides, and the oarsman can sit on a cooler or even a slant board for a seat. Catarafts: Cats are the invention of Russian recreational boaters for extreme whitewater use, and most Russian cataraft designs use paddlers instead of oars, and the paddlers commonly kneel on the tops of the raft tubes. But then, the Russians have invented quite a few other strange whitewater crafts as well. None have taken hold for use in the USA as has the cataraft. More info here Catarafts are generally just two (sometimes four) inflatable tubes tied together with a frame on top. Width of the boat is primarily determined by the width of the frame, and some cataraft frames are made to have an adjustable width. Generally, there is no floor, or at least none that is in regular contact with the water. Some people suspend webbing or a trampoline floor from the frame, and others use wooden planks or aluminum panels for a firmer floor. Of course, nearly everything you add to make life more comfortable also makes the boat heavier too, and somewhere you have to set a limit. Since catarafts always have some form of frame, they are nearly always outfitted with seats and oars. There are a few catarafts that are exceptions though. A cataraft’s weight capacity is determined by the length and diameter of the inflatable tubes, and since they have no floor to help support the weight, they can carry less than a round boat of the same length. For instance a 14’ Aire Series E raft has a published capacity of 1800 lbs, and their 16’catarafts have published capacities of 1600 to 1800 lbs, depending on the model. Keep in mind that these weight limits are for large easy rivers. If serious whitewater exists, or you are trying to float a low water stream, you don’t want anywhere near that much weight in them. Also, since catarafts have a more extensive frame to tie the tubes together they generally weigh more than a conventional round boat, and take more time to set up. But catarafts can also be broken down into smaller pieces to more easily fit inside smaller airplanes. Catarafts have the advantage of speed and ease of rowing compared to round rafts. They also punch holes and reversals better, and generally being wider, are more stable as well. Catarafts in general are better whitewater boats, but since they don’t pack as much weight you seldom see whitewater outfitters using them to carry passengers. However, they do use them as safety escort boats in very rough water. Another thing that you can do with a cataraft is put large outboard motors on them. They don’t have an efficient planing hull, but with enough power you can get them up and moving rather briskly. However, you can count on water spraying everywhere while it’s doing it, so plan on getting wet. Raft frames: Frames can be made out of many materials. Early Russian cataraft frames were generally made out of wooden poles from nearby trees that were simply lashed together. Most boat frames today are made of metal tubing, aluminum being the favored material. This tubing can be welded, or with the use of special fittings, can be bolted or pinned together. I use a combination of both wood and aluminum for one of my frames, and have also resorted to felling small trees for additional frame members after a fly in river access. 2x6” or 2x8” boards are also commonly used for round boat frames. You can set up your frame to row from near the front, near the back, or in the middle. Rowing from the front works best for pulling yourself from large holes/reversals because you can plant your oars into firmer moving water at the bottom edge of the holes. But you may not like rowing from there. From the front it's harder to tell which way your boat is starting to swing until it gets around quite a ways. Rowing from the rear allows you to see most of the boat in front of you. It helps you gage direction better, and you can also see what any part of the boat might be about to hit. Rowing from the center is quite popular. On lightly loaded boats it gives you a feeling of pivoting your boat in the middle, which works well. It also helps balance the load with gear or passengers piled in both front and back. Either way keep you load as low as possible to reduce undesirable effects from wind, and to assist with balance. In the end rowing placement is mostly personal opinion. Oars: Oars are commonly constructed of wood, aluminum or composite materials. The oars are connected to the raft frame about 1/3 the way down from the handle, and can use either oarlocks or pins and clips. If using oarlocks, generally the oar is fitted with a stopper that keeps the oar from sliding all the way out through the oarlock. Below this stopper there is generally a sleeve about 18” long that protects the oar and causes it to fit tightly within the oarlock. There also may be added a plastic upright (spine) along the top of the oar to keep the oar oriented correctly for the blade to intersect the water at the right angle. Often there will be added a cord or strap that is allowed to slide along the oar just outside the oarlock, and is tied to the raft frame. This “keeper strap” is a safety device to keep the oar from getting lost in the middle of wild water. Pins and clips can be used instead of oarlocks, and they basically do the same thing. The pin sticks up from a mount on the frame, at about a 20 degree angle, pointing outward along the side of the raft. The oar is then fitted with a heavy duty clip that tightly engages the pin. The oar and clip can be pulled out from the clip to ship the oars, but normally they stay together. Often there is a flexible stirrup attached to the pin that encircles the oar to help remount the oar if it comes out in rough water. Generally, there is no keeper strap needed if there are oar stirrups. If you use pins & clips instead of oarlocks, and your stands are too short, causing your oars to bang against your knees, you can get an extra long pin (12"), and put a piece of plastic pipe between the stand and the stirrup to take up this extra length and raise the stirrup. Use the same material as the pin sleeve for this and cut into 1 inch sections so you can use pieces above or below the main stand hole to adjust the pin hight. Drill a small hole in the bottom of the pin and use a clevis to keep it all together. A large nut at the bottom is more common, but only makes adjustment more difficult. Always pack an extra clevis. Long bolts for this can be purchased cheaply at hardware stores. Another trick with pins & clips is to take the sleeve that is between the stirrup ends (the part the oar rides against) and cut in in half. Then place very large washers at the new break you just cut. Now you can row from the bottom position (below the washers) when you need the best power position to row for distance, and comfort, but use the "upper birth" (oars resting on top of the washers) for rougher water. The reason for this is that when the boat starts rocking violently you often can't get the oar out of the water when it's rocked the wrong way (one side always is it seems) and the shafts keep banging into your knees while you try. On the upper birth you have more room to clear your knees and still row when it's violent. As to which to use, pins or oarlocks, it’s your choice. It is generally proposed that pins and clips are better for rough water use, but oarlocks have successfully been used for rough water for many years so the difference isn’t all that significant. Pins and clips generally have more slop in them causing a lot of rattling and banging around noises, while with properly fitted oarlocks the most you usually get is an annoying squeak from time to time. Either way, oar stands should be canted outward so that the pin or oarlock is perpendicular to the oar while the oar is in the water in a pulling position. This keeps binding at a minimum, and allows for the most range of vertical motion. Since oars are commonly not quite 1/3 in the boat, and just over 2/3 out of the boat, suggested oar length is primarily determined by the with of the frame at the oarlocks or pins. If the oarlocks are mounted on your frame 7’ apart (that’s about where they fall on a 6’ wide frame), and you want a 1’ gap between the ends of the oar handles in front of you, there remains room for two 3’ oar handles inside the boat. With 3’ handles inside the boat, you ant to use 9' to 10’ oars for your 6’ wide frame. This is a very rough guesstimate, as some people want less gap between the handles, and some oarlocks are mounted higher (with a correspondingly higher rowing seat). Both situations would require a longer set of oars. Here is a page showing the differences between oarlocks and pins. They make some assertions about noise that I don’t agree with, but the pictures are good. You want access to the spare oar close at all time. on way to do this is to arrange the spare with the blade near the rowing position, where you put a strap at the narrow part between blade & shaft. This strap holds the blade end of the oar and keeps the oar from sliding forward or back. The handle is then run in the opposite direction, tucked into a strap or a ring, but loose so you can pull it free after removing only the strap at the blade. There are plenty of other ways to do this, but you want fast access to this spare no matter what else you do. Hardware: the most common piece of rafting hardware you will see all the time is the lowly raft strap. This is just a nylon or polypropylene strap with a cam buckle on one end. The other end is generally run back into the cam buckle making an adjustable length loop. These are very strong and are used to tie the frame to the raft. The best way to use them for frame mounting is to put them on so that they tighten by pulling up on the tag end, not down. This allows you to tighten them from inside the boat. Another tip is to wrap the strap an additional turn around the raft's D ring to keep the strap from slipping when you tighten it. Raft straps are also used to tie all the gear into the boat, and the boat to the trailer when it’s all done. Once you have purchased a large selection of these, you will always have several in your car, motorcycle, ATV, and snowmobile. They are that useful. Buy lots of them. You can also sew your own by buying strap material and cam buckles from several suppliers. Here’s an image of what we are talking about. I like the ones from NRS that have the length sewn into the strap. It makes finding the right one much easier. Straps should be put on so that the tag end is pointing up. That way if one si loose, you can give it a quick yank while standing inside the boat to tighten it up. If it's pointing down you have to lean way over and tug downward and that's not easy when riding. This seems totally opposite of logic when you're standing along side the boat rigging it, so you have to make a conscious effort to change your thinking and actions. This is not a big deal on round boats, but on a cat with 16 or more straps tying the frame down, it becomes an issue. Another trick with straps is to put two wraps around the D ring before stringing it around the frame. This keeps it from slipping when you administer that yank. Other common pieces of hardware used for rafting are: A throwable rope bag, used for a safety line. These throw bags usually have 50-75’ of polypropylene rope in them. 3/8” rope is easier to hold than thinner rope so it works better for safety uses. A bow line and stern line are also very useful. The bow line should be about 75’ long to give you enough length to tie your boat to a tree or rock up the shore and away from the water’s edge. A "chicken line" of ½” rope generally encircles the boat to give swimmers something to grab even if the boat is up side down. Speaking of up side down, you might want a couple of flip lines attached to the sides of your boat too. These are small bags with about 10' of thin rope in them. If the boat flips and doesn’t self right (they almost never do), you climb on the boat floor, grab one of these, move to the other side of the boat, and hang onto the line while you lean way out over the side. If all goes well, the boat turns upright as you fall back into the water. Then climb back in and get to rowing. Hopefully, your boat is self bailing. You should also consider carrying an extra length of strong rope (polypropylene is generally preferred as it floats), a couple pulleys, caribiners and prusik loops to be used in rescuing boats that are stuck on rocks or in log jams. There are some good books on whitewater rescue and boat recovery that will teach you how to make Z drags and such devices to get you out of trouble and recover your boat too. Rigging boats: There are plenty of alternative methods used for attaching frame and gear to rafts, and some of them even work. One thing you always want to do is keep all gear, especially hard gear, off the bottom of your raft. Even with self bailing floors, there are too many times when a rock rises up from the floor to meet your cooler, and “poof,” you have a hole in your shiny new self bailer. Commonly you will see people load gear directly on an inflatable self bailing floor. This shouldn't be done, but people get away with it all the time so it continues. But by all means, do not place hard gear on a single layer (tub) floor. You will get holed. You should suspend trampolines or platforms from either the frame members or from the D rings along side your boat. You may have to add more D rings to the bow and stern areas to do this right. They are not expensive and are to easy to glue on. Coolers and dry boxes can be hung from the frame with special straps designed for this purpose or you can use standard raft straps. If you are not using a frame, and gear must be placed on an inflatable floor, put soft stuff on the bottom and hard boxes and coolers on top. In any case put all your gear in waterproof bags or boxes. With catarafts every thing is suspended in one way or another. Some from frame mounted straps, some on the floor that is suspended from the frame, and some placed directly on the tubes and lashed down. Gear piles should be made in one or two areas with room left for passengers to move about a bit. Generally one big pile is behind the oarsman. If you do it right you can use the pile as a back rest. Make sure you tie each piece of gear into the boat. You can use one long strap to go through loops and buckles on several bags and boxes, but make sure you get them all, and that all are tied securely to the boat. Buy lots of long straps to do this. You can also place a cargo net over the top of it all, but the net alone is often not enough to keep everything together if the boat flips. Additional small gear piles can be placed around the rowing area, but it is very important to keep clear all the areas where the oar handles swing. You need to keep the rowing area clear, so you can row freely, and if need be, you can swing your oar handles fully forward or back to avoid obstacles in the river. [edit] Where to Start Rafting in AlaskaWhere to Start Rafting in Alaska [edit] Information Resources
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