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photo technique / technical reference / the big photography list
Every so often I pick up some great paddling and boat repair/maintenance tips from my club's discussion groups and I will be posting the better exerpts here. On fixing rope skegs:
The skeg should slide in and out of the skeg box fairly easily by pulling on the skeg blade when in the down position. The channels in the box align the axle in the proper position. The only thing keeping it in the box is the bungie tension and, when cleated, the line. If the skeg does not come out easily, it indicates a problem, usually a mismatch in tolerances between the box, the axle, the hubs and the skeg blade itself. All of these can be adjusted. It is important that you can get the skeg in and out easily; it was designed that way to make it easy to unjam the blade and to do field repairs. The skeg should also raise and lower easily with minimal resistance or sticking. If it does not snap up and down effortlessly, it can usually be fixed, albeit with tinkering. Don't settle for a sticky skeg! What we found: One NDK Explorer had always had a very sticky skeg. When we tried to pull it out of the box, it stuck halfway and four strong hands with feet on the hull couldn't budge it. Leverage finally did the trick. The fix was to grind the ends of the axle on a power drum sander: essentially the axle was too long (or the skeg box too narrow). Less than a 1/16" or so on each side did the trick. A second problem with this same boat was that the hubs had been pressed together and were pinching the blade. So we had to pry the hubs apart a bit to provide more room for the skeg to pivot around the axle. When fixed, the skeg slid in and out of the box easily and also pivoted easily. Another Explorer had a skeg that went in and out easily, but did not pivot well. The hubs were at the proper tolerance. The solution was to pry the hubs off the axle (gently) and enlarge the hole in the skeg blade with sandpaper. A little sanding with fine paper was also done on the axle to clean it up, but too much of that and the hubs would no longer fit snugly on the axle. Overall, there are several tolerances that need to be correct: the skeg blade hole around the axle (loose enough to pivot freely), the press fit of the hubs onto the axel (tight enough not to move but loose enough to adjust), the slight spacing between the hubs and the blade (wide enough to allow free skeg rotation but close enough to keep the skeg in line) and finally the axle fit in the channel in the sides of the box (free to slide in and out but with little play). Generally, we found it easier to alter the skeg components than the skeg box. A power drum sander (both hand drill and drill press) was used to grind the end of the axle, but hand sanding was needed for the tight tolerances. Sometimes, the skeg box itself is the problem (crooked, too tight, out of alignment), but we didn't find anything during the workshop we couldn't fix by adjusting the skeg assembly. Some use lubricants on the axle, hubs and in the box to make the skeg move smoothly. Silicone or other high tech lubes do work, but can attract grit and gummy crud. In principle, lubes should not be necessary given the design: the only surfaces that should touch are the inside of the skeg blade hole against the axle and this need not be a tight tolerance. If lubricants are a necessity, you may have some other problems. In particular, the hubs can get too tightly pressed against the blade. Simply pull the assembly out of the box and gently pry the hubs away from the blade slightly. Rope skegs may do better after being re-rigged with heavier line and bungie. Many find the original NDK rope too thin and it appears to be a nylon braid, which stretches. I've found a polyester core line to give more positive control. Lines and bungies that are too thick begin to bind in the tube down through the deck. A stiff rope has the same problem: it doesn't run smoothly around the pulley and down the tube. Another binding problem in the tube is the result of line being pinched by the bungie. Aside from getting the right diameter, put the bungies in first and then take care to thread the line where it won't bind. If that doesn't fix the binding, check the tube itself. The stock NDK design has a fiberglass tube or nipple projecting up from the skeg box and down from the deck. A short length of plastic tubing bridges the gap and is fixed in place with a hose clamp on either end to waterproof the stern compartment. After 3 seasons of sticky skeg problems on my Romany 16, I discovered that the tube had been kinked at the factory, pinching the skeg line. (The tube was a bit too long or had not been fully pushed onto both fiberglass tubes, so it squished together like an hourglass in the middle.) In fact, it was tight enough not only to bind the skeg rope, but forced the line to almost cut through the plastic wall. I replaced the plastic tube with a heavy clear vinyl tube which solved the problem. The installation can be tricky as there is only about 1-1/2" separating the ends of the respective fiberglass tubes and it's tough to get both ends of the vinyl tube onto their respective nipples while dealing with the hose clamps and the restricted space. After 15 minutes of frustration, I heated the vinyl tube in boiling water for a few minutes and with the new flexibility it went on easily. A final binding problem can stem from the bungie or rope getting pinched between the hub and the wall of the skeg box. The fix it to replace the bungie around the shoulder of the hub and make sure the rope feeds straight up. A varient of this binding problem is the knot in the end of the rope where it ties to the blade. If your knotting technique leaves a lump it can rub on the wall of the skeg box. One quick fix is to pull the knot out of the depression in the blade, heat it with a match and while still gooey, pull it back to the blade and squash it down with something flat. Custom fit! We saw a cool trick at the workshop: tying a couple of knots in the line where it slides through the jam cleat to index various positions of the skeg, e.g. up, down and halfway. The knots need to be small enough to slide easily through the fairlead built into the jam cleat. Low tech and slick. I've seen it done on other boats by using a permanent marker to mark index lines on the line itself which also works. The advantage of the knotting system is that with some experience, you can set the line by feeling the knots as they pass: no need to look down. Another trick is to drill a small hole in the tip of the skeg blade and thread a light line through it. Tie it into a loop that hangs down below the hull a couple of inches. When the skeg jams, you can simply reach under the hull and pull down on the loop. A good knot gives you something to grab or you can put your fingers through the loop for a really hard tug. This is easy for your paddling partner to do on the water. You want to keep the line thin to minimize drag in the water. We had two boats at the workshop with the newer (2003 vintage) forward mount rope skeg setups. The idea was to have the advantages of a rope skeg (no kinks and field reparability without tools) with the advantage of being where it can be seen. Good idea, not so good design in my experience. The rope is routed through a hole in the deck about where the jam cleat on the old style rope skeg is mounted, follows a plastic tube under the deck inside the coaming and exits into a molded depression about where a cable knob would be mounted on the deck. The rope goes through a small pulley and up to a flat jam cleat (mounted backwards in my view) that are both set into the depression. In my opinion, there seems to be too much friction to work smoothly. More importantly, it would be a bit of a chore to thread a new line down the tube and the relatively thin stock line cannot be upgraded without replacing the tube. This would make field repairs fussier, one of the things a rope system is supposed to avoid. One of the Explorers with this design was mine so I re-rigged it with the older jam cleat behind the cockpit. This simply involved removing the hardware on the deck and the under deck tubing, plugging the resulting holes (I used epoxy putty but silicone caulk or glass would do as well), and installing a jam cleat in the traditional position. I find both the Romany 16 and Explorer relatively neutral to wind forces which can be effectively compensated for by edging and minor corrective strokes. As a result, I've only used the skeg out of necessity a few times. However, under the right conditions, either boat will weathercock with a vengeance and in those situations a skeg is a major convenience and may be a real safety feature. Getting it and keeping is working smoothly will take some fiddling, but can be done. And an Addition by Brian N.:
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