 This program covers the procedures to follow for sander calibration. The first thing you should know is that every sander in the state is different. So each and every one has to be calibrated every fall before it begins to snow. Basically calibration involves loading the sander at least half full, setting the gate opening precisely, discharging salt at various chain settings, weighing the amounts of salt discharged, and then doing some simple calculations. Of course to calibrate a sander you'll have to have some equipment and some help. This procedure requires at least two people. So let's look at the equipment you need first, then we'll go through the procedures in detail. To begin with you'll need a torque to catch the salt, a scale to weigh the salt, the department forms detailing the calculations and procedures, a calculator, a tape measure, and a watt with a second hand to time the discharge of salt. Okay that's the equipment. Now let's go through the procedure. The first thing to do is to get a load of salt, but be sure to leave enough room to work between the stockpile and the truck. It's important that the hydraulic oil is warm before calibrating the sander, so run the chain for a few minutes before you load the truck. Now as I said earlier, you'll need at least a half load of salt, but it's even better to get a full load. That way there will be no question that there's enough salt over the chain, and be sure to use salt. The entire procedure is based on the known weight of salt. The weight of pre-mix varies, so pre-mix is unacceptable for calibration. Okay the sander is loaded and the hydraulic oil is warmed up. Now you can begin filling out the worksheet. As you can see the top of the form calls for the numbers of both the truck and the sander. So before doing anything else, make a note of both numbers. The form can't do you much good if you don't know which truck and sander it's for. Remember not only is every sander different, but the hydraulics in the trucks are different too, and the hydraulics certainly affect the calibration. The next section of the form requires the gate setting for spreading a quarter cubic yard per two-lane mile. Now if you can't remember the gate setting you used last year, try three inches if it's an old truck, or two inches if you have a new truck. When you set the gate, be sure to use a tape measure because some of the scales marked on the sanders are inaccurate. And always set the tape measure on the floor of the sander as you see here. Okay the next step is to set the chain speed at two and count the number of shaft revolutions in one minute. Now this step calls for starting and stopping the chain at exact times, so be sure to discuss the hand signals you use before going any further. Then bring the truck's engine up to operating rpm and mark the sprocket so you can easily count the number of revolutions. All that's left for this step is to signal the driver to start the chain and then record the number of revolutions in one minute. In this case the shaft made three revolutions. Now count the revolutions with the chain speed set at six and then at ten. As you can see this part of calibration is pretty simple. It's just a matter of signaling the driver for the chain setting to use and counting and recording the number of times the shaft revolves in one minute. So for this particular spreader the chain revolved three times when the chain speed was set at two, nine and a half times when it was set at six, and fifteen times when the chain speed was set at ten. Remember the gate setting stays the same. Okay now as you can see we've discharged a few hundred pounds of salt in three minutes. So pull the truck ahead so you have room to put the top under it and be sure to note the weight of the empty torque. This particular torque weighs four pounds. Now the worksheet calls for the number of pounds discharged in one revolution. So with the top under the sander signal the driver to start the chain at speed two and as soon as the shaft has made one revolution signal the driver to stop the chain. Okay. Then carefully gather the salt in the torque and weigh it. In this case the spreader discharged 25 pounds of salt after one shaft revolution with the chain speed at two. But remember to deduct the weight of the top when you record the weight of the worksheet. So 25 pounds minus four pounds for the top gives us 21 pounds of salt. The next step is to weigh the amount of salt discharged in one revolution with the chain speed set at six and then at ten. So as you can see weighing the material is fairly simple. All you have to do is signal the driver which chain speed to use and to stop the chain after exactly one revolution. Then weigh the material for each chain speed and record the weight of the salt only by subtracting the weight of the torque. At this point we've done all the measuring we need to do to calculate the miles per hour when spreading 0.25 cubic yards per two-lane mile. The next step is to make the calculations for spreading a half a cubic yard per two-lane mile. As before use the gate opening you used last year if you can remember. If you can remember a general rule is to just double the gate opening you used for a quarter cubic yard. So in this case we'll use four. Once again set the gate opening with the tape measure resting on the floor of the sander. The revolutions per minute of the chain shaft are not affected by the gate opening so you can copy the numbers you counted before. Now all you have to do is weigh the material discharged in one shaft revolution for each of the three chain speeds. Again all that's involved is signaling the driver which chain speed setting to use then signaling the driver to stop the chain after exactly one revolution then weighing the material and recording the weight of the salt only by subtracting the weight of the torque. Now let's go through the calculations. Again the procedure is pretty simple. All you have to do is multiply the number of shaft revolutions per minute by the pounds discharged after one revolution by the factor given on the worksheet. So three times 21 times point one two equals eight. Then just continue multiplying the numbers in each row. The next step is to transfer the numbers in the miles per hour column to the graph. The rows on the graph are for the chain setting and the columns are for the miles per hour. So to put the numbers on the graph just read up the miles per hour column until you reach the proper chain setting. For example we came up with 32 miles per hour with the chain set at six. So to mark the graph just read up the 32 miles per hour line until you reach the six for the chain setting and mark an X. Put the other two numbers on the chart in the same way. When you've marked all three numbers draw as straight a line as you can through the three X's. They won't always line up exactly. Now the last step filling out the sander spread chart. The first thing to do is to write down the truck and sander numbers. Then write in the gate opening that you use for 0.25 cubic yards per two lane mile. Now to find the chain setting for each of the miles per hour just read up the miles per hour column until you reach the line that you drew. For example to find the chain setting for 25 miles per hour read up the 25 miles per hour column until you reach the line you drew. Then look across to find the chain setting. In this case the chain setting should be five because it's the closest to the line to spread a quarter yard of salt per two lane mile. Continue reading up the miles per hour column finding the chain setting for the rest of the miles per hour listed on the sander spread chart. When you're through follow the same procedure to find the chain settings for placing a half a cubic yard of material per two lane mile and it's a good idea to use a different color pen so that you can easily tell the two lines apart and that's the procedure for sander calibration. As I said in the beginning of the program be sure to have the department procedures on hand when you go through the calibration and you shouldn't have any trouble.