Two capacities, one bale weight that reconciles them
The defaults describe a 48 by 30 by 36 in bale, which is 30 cubic feet, weighing 450 lb. That is 15 lb per cubic foot. In a trailer 48 ft by 8.5 ft by 8.5 ft usable, the floor takes 38 bales turned the better way and the height takes two tiers, so 76 positions. Filled, that is 34,200 lb against a 44,000 lb payload.
So the floor fills with 9,800 lb of payload untouched. Divide the payload by the 76 positions and the balance point falls out: 578.9 lb a bale, which is 19.3 lb per cubic foot. Below that number the trailer cubes out and above it the trailer weighs out. Bales are whole things, so there is a narrow band around the balance point rather than a single weight: anywhere the payload divided by the bale weight rounds down to the same number of positions the floor gives, the last position and the last pound run out together.
The point of putting it that way round is that bale weight is a machine setting and payload is not. You cannot make the trailer bigger. You can sometimes make the bale heavier, and now you know by how much: 129 lb a bale, or about four and a third pounds per cubic foot.
Turning the bale changes the count
With the default bale, laying bales lengthwise gives twelve rows of three, which is 36 to the floor. Turned across, it gives nineteen rows of two, which is 38. Two positions is not much until you notice it is two tiers deep, so four bales, which is 1,800 lb on the default. The page prints both grids so you can see which way round it worked out and by how much.
Height is coarser and matters more. At 36 in a bale and 102 in of usable height, two tiers fit and a third does not, with 30 in left over. Six inches off the bale height would not add a tier; thirty would. That is the kind of step that makes a bale dimension worth arguing about with whoever specified the machine.
Freight is mostly indifferent to weight
Enter a line haul figure and the page divides it by the tons actually aboard. On the defaults, 850 dollars across 17.1 tons is 49.71 a ton. At the balance point the same trailer would carry 22 tons, and the same 850 dollars becomes 38.64 a ton. The freight bill did not move. Nothing about the trip changed except how much material was inside it.
That is the whole argument for density in one line, and it is also why a light stream is a worse freight problem than a heavy one. Heavy material wastes floor space, which is free. Light material wastes payload, which is not.
What this does not settle
Whether the baler will make a heavier bale of that material, whether the tie will hold it, whether the stack is stable, and above all whether the loaded vehicle may legally travel. The payload field is a number you enter because it depends on the vehicle, its axles, the route and the paperwork, and none of those are visible from a calculator. A load that fits inside the box and a load that is lawful to move down the road are two separate questions.
Questions people ask
How do I work out bale density?
Weigh the bale and divide by its volume. The default 48 by 30 by 36 in bale is 51,840 cubic inches, which is 30 cubic feet, so a 450 lb bale is 15 lb per cubic foot or 405 lb per cubic yard. Measure a tied bale that has been sitting rather than one still in the chamber, because bales relax, and average several because bale weight moves with the material and with how the machine is run.
What does it mean for a load to cube out or weigh out?
Cubing out means the space ran out first and the payload still had capacity in it. Weighing out means the payload ran out with floor positions still empty. On the defaults the trailer cubes out at 34,200 lb against a 44,000 lb limit, so 9,800 lb of payload is being carried around as air. The page names which one happened and prints the gap.
How many bales fit in a 48 ft trailer?
It depends on the bale, and on both dimensions rather than either alone. The default bale gives 38 floor positions turned the better way and two tiers, so 76 slots by space. Whether all 76 travel depends on the payload: at 450 lb each they do, at 700 lb each only 62 would, and the trailer would then be leaving fourteen positions empty.
Is a heavier bale always better?
Only up to the balance point, and then it stops helping. Past the weight where floor and payload run out together, extra density buys nothing on this trailer, because the limit has moved to the payload and no amount of compaction changes that. The page prints the balance point so you can see where the return stops rather than assuming denser is always better.
What is the compaction ratio for?
It converts between the yard floor and the trailer. At the default 60 lb per cubic yard loose against 405 baled, one bale is 7.5 loose cubic yards, a ratio of 6.75 to one. That is the figure that tells you how quickly loose stock disappears when the baler runs, and it is the same figure that decides how much floor you need if it stops.