Ice Resurfacer Water and Shavings Calculator

The snow tank fills faster than anybody plans for. A blade set a sixty-fourth of an inch deeper across a full sheet is another cubic foot of ice off the floor per cut, and by the fourteenth cut of a tournament Saturday that is the difference between one dump and two, which is the difference between finishing the flood and holding up the next game. This works the shavings, the dumps, the water and the melt from the blade setting outward.

Only read when the selector above is set to a measured area.
A sixty-fourth is 0.016 in and a thirty-second is 0.031. If you do not know yours, dump one full cut into a measured box and work backwards from the volume.
The edges, the creases and whatever the machine cannot reach are not being shaved. Your own driver knows this number better than any table.
Loose volume divided by the solid ice it came from. Fill a known box from the tank chute and measure it once.
From the machine data plate or your own measurement of the box.
Zero if you do not run wash water. From the machine settings or a timed fill.
From the tank meter, not the tank size. Most machines lay far less than the tank holds.
One per session plus whatever the schedule adds. A tournament day runs two or three times a normal one.
Measure the box. A pit that drains as it melts holds more over a day than its volume suggests, which is what the melt figures below are for.
From the property table you work from, or a core you cut and weighed.
From the property table you work from. Name the source in your own records.
From the property table you work from. This is the number that dominates every melt figure on the page.
Colder than the surface reading if the blade is cutting deep. Shoot the pile with your own thermometer.
Off the appliance data plate. Put 100 in if the pit is unheated and you only want the raw heat figure.
From your own bill. Set to 0 to leave the fuel cost out.
Ice Resurfacer Water and Shavings Calculator per CutBuildFigure

What a cut actually removes

Take the default sheet — 16,327 square feet after the corners — and assume the blade reaches 92 per cent of it. That is 15,021 square feet. At 0.015 in of cut the machine lifts 18.8 cubic feet of solid ice, which is 0.70 cubic yards and 1,074 pounds. It does not go into the tank as solid ice, though: shavings come off broken and full of air, and at a 1.6 swell factor they take up 1.11 cubic yards of the tank.

A 2.5 cubic yard tank swallows that in one go. Set the blade to a thirty-second instead and the same cut makes 2.3 cubic yards, which still fits, barely — and on a sheet with no corner radius it does not.

The pit is a melting problem

Fourteen cuts a day is 15.6 cubic yards of loose snow and 15,036 pounds of ice. Melting it is 144 Btu a pound before you have warmed anything, so the day makes about 2.4 million Btu of work for whatever heats the pit, and it releases 1,802 gallons of water into the drain. Warming that same ice from 18 °F up to freezing is only 6.9 Btu a pound — four per cent of the job. Pits get undersized because people size them for the warming and not for the melting.

Water in against water out

The same day puts 2,660 gallons through the meter as wash and flood water and returns 1,802 gallons of melt to the drain. The two are not the same number and should not be: flood water stays on the sheet as ice until the next blade takes it off, so the balance only closes over the life of the ice, not over a day.

What this cannot know

It cannot tell you how deep to set the blade. That depends on the ice, the event, the driver and how much build-up the sheet has, and getting it wrong in either direction has costs this page does not model. It also assumes a uniform cut, which no machine makes — every sheet has ridges and hollows and the blade takes more from some places than others. That is what a drilled survey is for.

Questions people ask

How do I find my swell factor?

Dump one full tank into something you can measure — a bin, a bounded corner of the pit, anything with a known volume — and level it. Divide that loose volume by the solid ice volume this page works out for a cut. Once you have the number it barely changes.

Why is the melt figure so much bigger than the warming figure?

Latent heat. Turning ice at freezing into water at freezing takes about 144 Btu a pound and does not change the temperature at all. Warming ice a degree takes about half a Btu a pound. Melting dominates any snow pit calculation by more than an order of magnitude.

Does the wash water end up as ice too?

Some of it. Wash water is picked back up by the squeegee and the vacuum, and how much comes back depends on the machine and the setting. This page counts wash water in what goes through the meter and leaves the recovery to you, because it varies more between machines than any figure a page could offer.

Should the pit hold a whole day of snow?

That is a design question for whoever built the building and it depends on whether the pit melts and drains as it fills. The page gives you the volume per cut and the cuts until the pit is full assuming nothing melts, which is the worst case and the useful one for a tournament weekend.

Why does the corner radius show up in a resurfacer calculation?

Because it is real area the blade travels over. Four per cent less sheet is four per cent less snow per cut, and across a season of cuts that adds up in the pit and in the melt bill.

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