BABYL OPTIONS: -*- rmail -*- Version: 5 Labels: Note: This is the header of an rmail file. Note: If you are seeing it in rmail, Note: it means the file has no messages in it.  0, unseen,, *** EOOH *** Path: yale!news-mail-gateway!daemon From: jl@cypress.com (John Lincoln/DCOM) Newsgroups: rec.sport.skating.ice.figure Subject: Re: How does a Zamboni work? Date: 7 Jun 1996 15:41:37 -0400 Organization: Yale CS Mail/News Gateway Lines: 75 Sender: daemon@cs.yale.edu Message-ID: <19960607154134.aaaa002tf@babyblue.cs.yale.edu> NNTP-Posting-Host: babyblue.cs.yale.edu Brian Zemach wrote: >Mike, >I know someone will prove me wrong, but an ice resurfacer basically >scoops up the snow upon the ice, melts it, then reapplies the water to >the ice surface. The zamboni with which I was most intimately involved >[g] used a couple of horizontal screws at the back of the machine to >move the snow to the center, where conveyor buckets lifted it to a large >bin that was very hot. >Brian Nope, that ain't quite how a zam works. If you take a close look at the carriage that is lowered to the ice as the operation starts, you will find a blade that runs the width of the carriage. This blade actually removes some amount of ice. The amount removed is controlled by the three adjustment shafts that you will find led to the drivers' seat. The center shaft controls the depth the entire blade cuts and the other two shafts control the angle the blade sits relative to the surface of the ice; these two controls are critical. If set wrong, you will build ridges on the ice, especially at the ends of the rink. So, the blade shaves off a controlled amount of the ice surface. This ice, now resembling snow, is moved to the center of the carriage by the counter-rotating screws. The snow is then picked up by a vertical screw to be deposited in the large bin forward of the driver and the hot water supply tank. In the early Zambonis, the snow was picked up by a conveyor belt that ran around the entire vehicle and through the carriage. You will see the drivers of current models often pushing a spring loaded control up and down. This clears the snow the accumulates in the vertical screw shaft; something that didn't occur in the conveyor belt models. The snow is not melted and re-used as hot water. The current snowbins are emptied by raising the rear of the bin and dumping the snow out the front of the bin like a dump truck in reverse. The older models with the conveyor belt usually had some arrangement using hot water to melt the snow and draining the remains through a pipe. In the real low budget models, you just had the shovel the stuff out. The water tank placed between the snowbin and the driver is filled with hot water before surfacing starts. At the same time the ice is shaved by the blade, the hot water is fed into what appears to be a folded towel about six to eight inches wide and running the length of the carriage. This evenly distributes the hot water on the ice. The amount of hot water applied can be controlled. The hot water serves three purposes. It is intended to fill in the skate blade ruts and pits that the surfacing blade misses, to replace the ice removed by shaving it and to create a smooth surface again. It should be obvious that you want to replace the amount of ice shaved off the rink by the blade. There are a lot of items to learn to control before you can do a decent job surfacing. Being a competitor at one time, my idea of a good surfacing job is a lot different that those of some of the twits now doing the job. The Zamboni also has the ability to suck up water from a rink where the surface of the ice has become wet; this can happen in warm environments especially if there are a lot of skaters. During surfacing, a lot of small pieces of flotsam that accumulate are picked up; hairpins, coins, earrings, contact lenses, peanuts, screws from skates etc. are also picked up. This is one reason why the snow is not melted and re-used outside of being an inefficient way of producing hot water. If the ice is getting to be too thick, you surface without using any water, possibly several times. The rink I worked at many years ago while in college used to do "dry cuts" (no water) for the competitor's freestyle sessions so that you couldn't do figures and you had to buy patch time. Patch ice was more expensive than freestyle time. If you have been to any competitions, you may have seen people walking out on the ice before the surfacing starts with a bucket of "snow" to fill any large pits created by the skaters. Any experienced skater knows that jump take-offs, landings and even some spins can create large pits and ruts that can't be erased by a normal surfacing. -jl