Four numbers, four different units
Run the defaults through and the shape of the problem shows up straight away. A 20,140 lb gross against a 12,380 lb tare is 7,760 lb of net. A 3 percent deduction takes 232.8 lb off that, leaving 7,527.2 lb of paid weight, and everything after that point is priced off the paid weight rather than off the net.
Then the prices arrive in three different units. Grade 1 is quoted at 42 cents a pound. Grade 2 is quoted at 210 dollars a short ton, which is 10.5 cents a pound. Grade 3 is quoted at 2.65 a pound. Nothing on a real ticket lines those up for you, which is why the page prints all of them in all five bases underneath the total.
Where the factor of a hundred lives
Per pound and per hundredweight look the same on a quote sheet. They differ by a factor of 100, and the mistake does not announce itself, because 0.42 per pound and 42 per hundredweight are the same price written two ways and both look entirely plausible. A load priced on the wrong one of the two is out by two orders of magnitude, and the only defence is converting every quote to one basis before comparing any of them.
The tons are the quieter version of the same trap. A short ton is 2,000 lb, a long ton is 2,240 lb, a tonne is 2,204.62 lb. Take a quote of 210 a ton: as a short ton that is 10.5 cents a pound, as a long ton 9.375 cents, as a tonne 9.53 cents. The same number on the page, twelve percent apart in what arrives.
The deduction takes weight, not money
A deduction line removes weight, so it costs you at the price of whatever it removed. On the default load, 3 percent of 7,760 lb is 232.8 lb, and the page prices that at the rate the load is actually running at rather than at a headline grade price. It also compounds with the split, because the deduction comes off before the shares are applied and every grade therefore loses the same fraction of itself.
The thing to check on your own ticket is whether the percentage is taken off the net or off the gross. Off the net is what this page does. Off the gross, on a load where the truck is most of the weight, is a completely different number and worth catching.
What it cannot know
Prices. Not one of them, not approximately, and not for how long. Scrap prices move week to week and between two buyers in the same town, and each of them quotes on whatever basis they favour. The grade split has the same problem in a different form: the shares are yours to enter, and the honest source is the sorted weights printed on the ticket rather than an estimate made standing in the yard, because the difference between a load that is 55 percent one grade and a load that is 40 percent is larger than it feels.
Selling scrap is a licensed trade in most places, with identification and record keeping attached to it, and some materials carry rules of their own on top. That is a matter for your state authority and for the yard, and this page has no opinion about it.
Questions people ask
How do I convert a scrap price per ton to a price per pound?
Divide by the pounds in whichever ton was quoted, and the whole trick is knowing which ton that was. A short ton is 2,000 lb, so 210 a short ton is 10.5 cents a pound. A long ton is 2,240 lb, so the same 210 is 9.375 cents. A tonne is 2,204.62 lb, so it is 9.53 cents. The page prints all three from whatever you enter, because the gap between them is around 12 percent and it is invisible on the quote itself.
Is the deduction taken off the gross or the net?
This page takes it off the net, which is the order most tickets use. On the default load that is 3 percent of 7,760 lb rather than of 20,140 lb, a difference of about 372 lb of paid weight. Your own ticket is the authority on which order it uses, and it is worth looking, because two yards quoting the same headline price can settle differently on the same load for that reason alone.
Why is my blended price lower than any of the grade prices?
Because the charges come off after the metal is priced, and because any share of the load with no grade against it still counts in the paid weight. The blended figure is the whole cheque divided by the whole paid weight, which is the number that tells you what the trip was worth. When part of the load is unpriced the page says so and prints the pounds it applies to.
Can a scrap load be worth less than nothing?
Yes, and the page says so when it is. A flat charge does not shrink when the load does, so a light or low grade load can cost more to present than the metal fetches. The result is printed as a cost rather than clamped to zero. What usually rescues it is another ton on the same trip, because the flat charge has already been spent by then.
What weight should I use for the grade shares?
The sorted weights off the ticket, each divided by the paid weight. Estimating the shares by eye is where most of the error in a mixed load lives, and it is a larger error than anything in the prices. If your yard does not print sorted weights then the shares are a guess and the total inherits that, which is worth knowing before treating the number as exact.