Now for something completely different. What’s going on at the Straightbrook quad? Two years ago Howie told me that was the next lift to be replaced, now Topridge is next. If they are gonna replace the lift I’m sure they didn’t put on a new rope this year. Why can’t they hold tension? If they can’t tension the rope on cold days how are they gonna tension it on warm days when it expands?
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It is actually the exact opposite of not being able to keep tension on the lift. Let me explain.
Straightbrook, and all of Gore's lifts have hydraulic tensioning. The hydraulic cylinder is set to always supply a constant force, but be allowed to either extend or retract to maintain it. This allows the tension carriage to move forwards (towards the opposite end of the lift), or backwards (away from the opposite end of the lift). There are limits on either end, which I will call the forward stops, and the back stops.
If a haulrope is too short, then it risks hitting the forward stops in certain weather and loading conditions. If a haulrope is too long, then it risks hitting the back stops. If either stops are hit, then the lift can't run, as the tension would either be too much, or too little. Too much, and you risk overstressing the haulrope, towers, and terminals. Too little, and you risk a rollback if the bullwheel can't maintain traction. Normally speaking, if the weather is cold, the tension carriage moves forward, while if the weather is warm, it will move back. If the lift is fully loaded, then the tension carriage will move forward. If it is empty, then it will move back.
When a new lift is installed, or undergoes a haulrope replacement, the length should be set on the shorter side to allow for stretching, but not so short that the tension carriage will hit the forward stops if the lift is fully loaded on a cold day. As the haulrope stretches, the tension carriage will get close to hitting the back stops. At this point, the haulrope needs to be respliced to shorten it and thus avoid issues.
I believe Straightbrook was respliced over the 2024 off-season, and it was cut too short. This puts the tension carriage at risk of hitting the forward stops. This is why when the lift is fully loaded on a cold day, it will go to every other chair, to lighten the load and keep from hitting the forward stops. Cutting the haulrope too short is a lot harder of a mistake to fix than cutting it too long. The only permanent fixes are to splice in another piece of haulrope to lengthen it, replace the entire haulrope, or hope for the best in that it keeps stretching so the issue goes away on its own. Note that to do either of the first two, it likely means multiple weeks of down time. So I think they're just hoping that it goes away on its own until a permanent fix can be made during the 2025 off-season.