Ricardo, on Feb 4 2006, 07:21 AM, said:
G'Day Folks
I'm a bit of a fan of Mueller lifts (I like the tower and sheave designs, can't explain the rest). They seem to have been popular in OZ during the 60's and early 70's (similar in Nth America also from what I can tell), and I'm curious to know whether they ever moved into the triple/quad and/or detachable designs at any stage?
From what I can see of Nth American installations, doubles seems to have been about as far as they got. Is that an accurate observation?
Any info apprecaited.
Richard.
I have been head of lift maint. at the biggest little mountain in NH for almost 8 years and I have had both the joy and the pain of working on two mueller doubles during my tenure here. I am unaware of the vintage of the lifts you inquire about but I can tell you all you need to know about our 60's vintage muellers. First, unless you have seen some with lifting arms there isn't much to appreciate about a mueller double tower design. In order to change a sheave you must have the famous 120 lb. portable lifting arm with 12,500 lb. rated tie back chains that you must carry up the tower and set up before you can even lift the haul rope from the sheaves. By the way, climbing a lattice tower in the winter with ice all over them is no picnic unless you have ladders which ours do not, and they didn't come with any. Due to the design of our mueller sheaves you cannot simply remove pressure from them by lifting the haul rope and inch or two to change the sheave, as the bearings are pressed on to a one-sided axle that is in turn, pressed into the wheel. You must completely open the sheave frame before you can even think about removing a wheel from the frame. Unlike Hall, Borvig, or Partek (three other brands of chairlift we have here) where just lifting the cable and inch and driving out either a through axle or pin to remove a sheave, mueller made this pleasantly impossible. Despite what some may think, this is not an enjoyable process when it is 80 degrees out, not to mention in the dead of winter. Ever heard of the Double-X Clamp? Let me educate you. Not one, but two cast "fingers" or "pullers" tensioned by TWO stacks of 56 spring washers housed in an aluminum "head". If you have never seen one, they are hard to picture as they are unique and unlike anything else you have ever seen. This grip has a bushing in the chair neck where the aluminum head pivots, hence the need for two fingers as the design creates a duel pivot point. The second finger slides through an aluminum "glide block" in the head that pivots side to side as the grips go around the bullwheel. This second finger also stabilizes the grip, preventing it from pivoting in two points. A complicated grip to be sure. Sometime in the 80's a seat broke free of its bail causing it to fall to the ground and the chairs had to be retrofitted with gussets that connect the seat to the bail. The original design had the seat mounted to the bail using only 4 5mm allen bolts. These bolts sheared as they obviously were not strong enough to hold the weight the carriers were meant to hold. Adding these gussets was an obvious improvement but created another problem all together. The neck of the chair is slid onto each side of the bail with four bolts holding it in place as the bail actually comes apart in two halves with the seat and the neck holding the two sides of the bail together. Adding these gussets prevents you from taking the chair apart easily to replace a neck if the need arises. And in our case, it arises from time to time. The primary weld located at the top of the neck where the grip bushing is installed has begun to present problems for us. Due to the age of our lifts it is a required procedure to visually inspect 10% of the chairs on line, primary welds daily after operating to the public. Granted, upgrades and retrofits are always an option, but in the ski business money and grandfathering laws always present a challenge. Though Muellers are unique and neat in a nostalgic kind of way, it seems to me that they were over-engineered and not built to be worked on without some choice words and f bombs being dropped now and again. So if you don't have a Mueller, or never worked on one, don't be too upset, you can just think of me upon some mountain freezing, wondering if I should have a Paleantologist Degree so I can better understand the Dinosaurs in my back yard.
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