Long Distance Trade

[Enoki]

I agree, the 30+ tons is far too big. There are several arguments against it:

It would require more specialized spacecraft to move it than a smaller container that many ships could handle. The handling equipment would also have to be larger and might not easily be available to move something that large on a lower tech planet.

It would be completely unwieldy on planets for movement. The container should be capable of being moved by a maximum of different transport means without having to break down the load or unload it.
Thus, it should be usable on lower tech as well as high tech planets. So, a railroad on a say, TL 5 planet can use them as easily as a TL 7 planet using something like a semi-tractor, as easily as a TL 13 world using grav vehicles. A 30+ ton would simply be too large for such movement.

A really large container like that might often have to be loaded with multiple shipments going to different locations. This would mean that it would have to be frequently opened, partially unloaded, a shipment removed, and potentially then reloaded with other items. That's a very unwieldly process. Better a smaller container going to one location in whole and being loaded and unloaded one time.

A large container isn't as flexible for loading into different size ships with different cargo bay configurations. For example, the 42 ton container suggested would be like 9 meters wide (6 squares)? That means it won't fit in most far or free trader cargo bays because their loading hatches are too small. On a subsidized merchant as given in LBB 7, it would fit through the rear loading hatch but not the front or side ones. It also would be close to the width of the cargo bay so only a few could be carried. Again, you'd have to be very careful with the loading order if you were going to more than one destination or you'd find yourself unloading and loading most or all of the cargo at each stop.

Now, for bulk freight like ore or say, wheat, or something like that, a ship that can hold it in its natural form in bulk would be best.

 

[Nathan Brazil]

Shipping costs again...

Live cows, err.... unprocessed products may contain wasted product tonnage. Gotta pay to ship the waste.

Or do you? Basic processing (removing chaff from wheat stalks, extracting base ores from unprocessed rocks) done onsite prior to shipment to another system. Your cost to ship remains the same (mass is mass) but the value of your good is higher because it is a more pure product and since your cost to ship is reduced. This can be taken to extremes but still would have to be decided for utility, risk and profit of each product Example: Is it more profitable (more value) in shipping 30 tons of perishable doughnuts (mmm doughnuts :rofl: ) vs 30 tons of relatively non-perishable breakfast cereal vs 30 tons of basic chaffed wheat.

 

[Condottiere]

Part of the problem is that Traveller is mostly made up.

It comes down to demand; if there exists some, and the price is right, the products will be offered.

Speculation tends to be risky, especially if it requires large capital outlay, and margins aren't stable within a certain range.

 

[Spinward Flow]

I agree, the 30+ tons is far too big. There are several arguments against it:

It would require more specialized spacecraft to move it than a smaller container that many ships could handle. The handling equipment would also have to be larger and might not easily be available to move something that large on a lower tech planet.

It would be completely unwieldy on planets for movement. The container should be capable of being moved by a maximum of different transport means without having to break down the load or unload it.
Thus, it should be usable on lower tech as well as high tech planets. So, a railroad on a say, TL 5 planet can use them as easily as a TL 7 planet using something like a semi-tractor, as easily as a TL 13 world using grav vehicles. A 30+ ton would simply be too large for such movement.

A really large container like that might often have to be loaded with multiple shipments going to different locations. This would mean that it would have to be frequently opened, partially unloaded, a shipment removed, and potentially then reloaded with other items. That's a very unwieldly process. Better a smaller container going to one location in whole and being loaded and unloaded one time.

A large container isn't as flexible for loading into different size ships with different cargo bay configurations. For example, the 42 ton container suggested would be like 9 meters wide (6 squares)? That means it won't fit in most far or free trader cargo bays because their loading hatches are too small. On a subsidized merchant as given in LBB 7, it would fit through the rear loading hatch but not the front or side ones. It also would be close to the width of the cargo bay so only a few could be carried. Again, you'd have to be very careful with the loading order if you were going to more than one destination or you'd find yourself unloading and loading most or all of the cargo at each stop.

I agree with each point, which is why I asked what the "basic container" size ought to be for interplanetary and interstellar shipping, because that's going to be the "multiplier" used to determine how many of those containers ought to be getting carried, and what size of cargo shuttle ought to be handling them in a multi-modal transport system.

Which then brings up the question of ... what is the "smallest standard cargo lot size" which then needs to be dealt with as a matter of routine.

Cargo: Starships may inquire at a starport about the number, sizes, and destinations of cargos awaiting transportation. The referee should determine all worlds accessible to the starship (depending on jump number), and roll for each such world on the cargo table. He should roll to determine the number of major, minor, and incidental cargos available on the world of origin; modifiers take into account the world of destination. After rolling for the number of cargos, roll one die for each cargo to determine its size. Multiply the die roll for major cargos by 10, minor cargos by 5, and incidental cargos by 1 to determine the number of tons in each.

So, we therefore get the following:

• Major Cargo = 1D x 10 (10-60) tons
• Minor Cargo = 1D x 5 (5-30) tons
• Incidental Cargo = 1D x 1 (1-6) tons

Needless to say, this gets a little bit messy for standardized containerization since the Minor Cargo sizes are not a direct multiple of the Incidental Cargo sizes. For the purposes of straight up scalable standardized containerization, it would have been better to do the following instead:

• Major Cargo = 1D x 12 (12-72) tons
• Minor Cargo = 1D x 6 (6-36) tons
• Incidental Cargo = 1D x 1 (1-6) tons

That way, you would be able to standardize everything onto the 6 ton (84m³) container as the "basic" unit of containerization for Incidental and Minor Cargoes, with the Incidentals representing a "partial container" cargo load that can be "shared" with other cargoes. Major Cargo would then use "double" containers to ship in 12 ton (168m³) increments.

Looking at the Subsidized Merchant deck plans (LBB S7, p20) and the 3.85 ton cargo module depicted there (3m x 3m x 6m) ... if you stretch that container to be 50% longer, you get 3m x 3m x 9m (5.78 tons) instead for a standardized incidental/minor cargo 6 ton shipping container. Major cargoes then use "double wide" containers of 3m x 6m x 9m (11.57 tons) to hold their cargo loads.

This then means that for passenger conversion, rather than using the basic 6 ton incidental/minor container to install a stateroom into and have 2 tons of waste space left over, you would instead be converting the 12 ton major container into 3 staterooms. Cluster 3 such containers together, giving you 9 staterooms, and you have accommodations for 8 high passengers with 1 steward to serve their passenger needs. Fit the passenger converted containers with connecting airlocks (I'm thinking at each of the 4 corners for maximum flexibility) so they can be "daisy chained" together like railroad cars (albeit in all 3 dimensions, not just 1 dimension along rails) and you're all set.

Such an interpretation of containerization then means that the standard cargo unit a shuttle would need to transport would be either 2 containers of 6 tons each, or 1 container of 12 tons ... in other words, everything ought to operate in terms of multiples of 12 tons (0.5x through 6x) for inter-modal transport via containerization to handle every type of incidental through major cargo type with maximum efficiency. Each container would classify as a 6 or 12 ton metal hull of Configuration: 4 (Close Structure) "box" shape, costing Cr360,000 per 6 ton cargo container (double that for 12 ton containers).

The most likely shuttle size for handling these cargo modules would then be a 20 ton shuttle with a 12 ton cargo bay, that has a bridge with no computer (the bridge is cheaper on Cr than a computer), leaving 4 tons left over for drives and fuel in an unarmed configuration. For armed shuttle types, you'll need 2 acceleration couches (pilot+gunner), a model/1 computer (weapons require a computer), 1 ton of fire control for the turret, leaving 5 tons remaining for drives and fuel, which could be enough to mount a pulse laser in a triple turret for a missile rack/pulse laser/sandcaster combo and still have enough EP for full Agility at all times. Minimum drive performance ought to be 2G maneuver and Agility: 1 (although 2 would be preferred) for cargo transfers from ship to shuttle to destination for loading and unloading operations.

It also means that if carrying one 1 major, 1 minor and 1 incidental cargo of maximum (1D=6 in each case) lot size each, a cargo bay would need to have 72+36+6=114 tons of available cargo space to carry them all in a single trip and require 9.5 (call it 10) tug shuttle round trips to load and unload everything.
The maximum cargo possible under LBB2.81, 11 from a population A world would be:

• 1D+6 Major cargoes
• 1D+7 Minor cargoes
• 1D Incidental cargoes

At absolute maximum capacity size for all (using the 72/36/1 containerization scheme, rather than the 60/30/1 scheme offered in LBB2.81) in which every single die roll is a 6 requires a cargo hold size of:

• 12 x 72 = 864 tons
• 13 x 36 = 468 tons
• 6 x 6 = 36 tons

864 + 468 + 36 = 1368 tons of containers (gotta load 'em all, gotta load 'em all!)

How does all of that sound? :coffeesip:

 

[Condottiere]

Future containers might be biodegradable.

 

[coliver988]

Future containers might be biodegradable.

And probably, as discussed by Spinward Flow, stackable and made to fit evenly into the next larger standard.

1 ton x 6 fits magically into the standard 6 ton container.

then there are 6, 12, 24 and 36 standards that can fit the 6 ton container (or 6x 1 ton containers for those smaller cargos going the distance)

Traveller has usually ignored actual physical dimensions for cargo: hey, I've a 50 ton cargo bay, I can fit 50 tons of ANYTHING in here. And that is generally good enough for an RPG. And the containers themselves may be 6 displacement tons but actual usable space should be less. But close enough for games.

A fun source for cargo containers and an intricate cargo profile is BITS 1001 Cargos. I've wanted to put in complex cargo codes for my players and then have things happen if they don't ask but have never done so. Safe for Vargr, not so much Humaniti....oh, you didn't scan the cargo manifest?

And finally: when I drive behind trucks that list the cubic meters, I'm always trying to divided by 13.5 or 14 to figure out the tonnage. Makes you realize just how BIG a 6 ton container would really be.

 

[Condottiere]

What comes first, chicken or egg?

Do you fit in containers within the existing infrastructure, or reconfigure the infrastructure to fit the containers?

If it's limited to existing road and rail networks, there might be little change.

 

[Spinward Flow]

Makes you realize just how BIG a 6 ton container would really be.

If you want to get closer to "no wasted volume" size for a 6 ton container size, you're looking at 3m x 3m x 9.33m which is 83.97 m³.

For the "imperial luddites" who can't stand dealing with metric measurement systems, that's 9.8ft x 9.8ft x 30.6ft which is 2938.8 cu ft.



Another alternative configuration, that would be more suitable for deck plans (now that I've had more time to think about it), would be a 3m x 4.5m x 6m form factor, which is 81 m³ (and you're back to 5.7857 tons again). In cargo bay deck squares, that's 2x3x4 squares. So for single deck (3m high) cargo hold spaces, you just lay the containers flat in 3x4 squares of deck space in the plans ... meaning that so long as the form factor of a cargo bay door is at least 3m high by 4.5 m wide, you can load a 6 ton standard cargo container into that cargo bay (playing Tetris inside the cargo bay however, is a different challenge).

In terms of multi-modal transport systems (in an out of game context), that 3 x 4.5 x 6 m container would equate to being just slightly under 10 ft x 15 ft x 20 ft ... so depending on which way you turn it to stick it on a ground transport truck it's going to be either a tall loading clearance for getting under bridges if transported vertical, or a wide load that occupies two lanes of roadways if laid sideways for needing to clear under lower bridges.

Hmm ... the 3 x 4.5 x 6 m form factor seems more sensible than the 3 x 3 x 9 m one, now that I think about it some more (although both would "work" as far as that goes).

You would still be doing a "double container" for the 12 ton major cargoes, but that would probably be either a 6 x 4.5 x 6m or a 3 x 9 x 6 m or a 3 x 4.5 x 12 m form factor. The main difference here would be the size of the cargo bay doors.

A single deck (3m ceiling) cargo bay would need doors that are either 4.5m (3 squares) or 6m (4 squares) wide on the deck plans to load a 12 ton container using 2 of the 3 form factors into an internal cargo bay. A double deck (6m ceiling) cargo bay would need bay doors that are only 4.5m (3 squares) wide to load all 3 form factors of 12 ton containers into it.

After that, it's just a game of Tetris with 6 or 12 ton containers to manage to fit them all into the cargo bay.

 

[whartung]

What comes first, chicken or egg?

Do you fit in containers within the existing infrastructure, or reconfigure the infrastructure to fit the containers?

If it's limited to existing road and rail networks, there might be little change.

You adapt the infrastructure. That's what we've done here.

You don't see trains filled with box cars any more, they're full of intermodal flat beds loaded with containers.

Containers use special ships, special cranes, special carriages, have large storage yards for arriving cargo and departing cargo and empty containers. The whole shipping industry is specialized around containers.

Because it's all about efficiency.

There's always the edge cases for things that just don't fit in to containers. Those shippers will pay more, and will take longer than container operations because they're off the happy path of cargo.

There's also specialized ships for specialized cargo. Oil tankers, ore haulers, car carriers, etc.

Mind, that's not to say that Free Traders are locked in to the tyranny of containers. They can be participating in that edge case. Part of why it takes longer and costs more.

The biggest case where the infrastructure didn't change is air freight. Those containers are built to fit airliners. And, mind I don't know, I bet that the containers are craft specific. I don't think that air cargo containers that fit a 747 will fit a 777, but I don't know. Maybe they have a more generic module now that fits the aircraft. Which suggests that fitting these containers properly is now a design constraint on modern cargo aircraft going forward.

There's a web page that list 15 different types of container for aircraft. I'm sure everyone in that space is consulting each other.

 

[Condottiere]

There's a reason that luggage is limited to thirty kilogrammes, and I'm pretty sure there's one for two times twenty five across the Pond, and that my briefcase has to fit under the airplane seat.

But containers still would have to account for railway gauges, and road dimensions.

 

[coliver988]

What comes first, chicken or egg?

Do you fit in containers within the existing infrastructure, or reconfigure the infrastructure to fit the containers?

If it's limited to existing road and rail networks, there might be little change.

see how Roman roads are the reason for the width of railroads in the US (which it turns out may not be 100% true but still is an interesting read)

 

[whartung]

see how Roman roads are the reason for the width of railroads in the US (which it turns out may not be 100% true but still is an interesting read)

All of these tie to the human size of things. If we were domesticating dinosaurs, we probably wouldn't be doing it with the enormous ones. As nice a draft animal a triceratops may be, it's pretty ungainly.

While folks try and make do with creatures like elephants, horse, oxen, and even camels work better since they're just easier to manage.

So, while the space shuttle boosters may be based on the size of two horses, the horses were chosen based on our sizes in the first place.

 

[Enoki]

see how Roman roads are the reason for the width of railroads in the US (which it turns out may not be 100% true but still is an interesting read)

Railroads are the width they are because that dictates the minimum radius / diameter a curve on one has to be with respect to the length of each car's wheelbase. Height is determined by bridges (overhead clearance) and tunnels.
Thus, there's a practical size limit--particularly in width--to railroads.

By the way, containers were first being used as early as the beginning of the 18th century. This was somewhat haphazard and applied to one good or another rather than being some standard used universally. The US military upped the use dramatically during WW 2 to make moving supplies easier. But these too were no universal standard. The modern shipping container was first standardized in 1956 by Malcom McLean in the US. He wanted his trucking company to be more efficient particularly when loading and unloading from ships. The containers had to fit the trucks in particular and that dictated size more than anything else.

 

[Aokhir]

What comes first, chicken or egg?

Chicken (because an egg that is capable of producing another chicken requires a secondary precursor chicken).

 

[kilemall]

On the "basket case" worlds, a ship carrying a known tonnage arriving on a regular schedule would still work. But the tonnage might be 200 to 1000 tons of freight.
The cost of delivery would be higher because the shipping company knows that at the delivery end there's little outgoing freight. If the shipper knew that local business had something to ship on the return leg, then the cost would drop for delivery. But going in loaded and coming back nearly empty would definitely raise the cost of delivery.

Now, if a shipping company can sucker in an independent ship and crew to make the delivery and bring back little at standard cost even if that crew lost money in doing so, then they're likely to be some unscrupulous ones that would do just that.

Shipping abhors a vacuum. If there is empty outgoing, something will be found to fill the space.


RL example, the US has all these shipping containers from Asia, carrying mostly Chinese and some Japanese goods.


Shippers have been finding animal feed, lumber, and other relatively raw material items to ship back.


Recently DFW got a collection station for empty shipping containers, then sends them to Houston to get filled with plastic pellets. The pellets are shipped back to China to be used as raw material for plastic items.


Something will be found.

 

[kilemall]

Re: containers, I just have it that there are 5-ton and 10-ton containers to service those CT lots corresponding roughly to the modern day 20 foot and 40 foot containers. They end up being a bit bigger volume wise but still doable for fitting down streets and of course gravtrucks.


As to long distance, what version are we talking as reference? Shipping cost per dton weighs heavily on this, as well as potential pricing differential.

 

[Timerover51]

I agree with each point, which is why I asked what the "basic container" size ought to be for interplanetary and interstellar shipping, because that's going to be the "multiplier" used to determine how many of those containers ought to be getting carried, and what size of cargo shuttle ought to be handling them in a multi-modal transport system.

Which then brings up the question of ... what is the "smallest standard cargo lot size" which then needs to be dealt with as a matter of routine.



So, we therefore get the following:

• Major Cargo = 1D x 10 (10-60) tons
• Minor Cargo = 1D x 5 (5-30) tons
• Incidental Cargo = 1D x 1 (1-6) tons

Needless to say, this gets a little bit messy for standardized containerization since the Minor Cargo sizes are not a direct multiple of the Incidental Cargo sizes. For the purposes of straight up scalable standardized containerization, it would have been better to do the following instead:

• Major Cargo = 1D x 12 (12-72) tons
• Minor Cargo = 1D x 6 (6-36) tons
• Incidental Cargo = 1D x 1 (1-6) tons

That way, you would be able to standardize everything onto the 6 ton (84m³) container as the "basic" unit of containerization for Incidental and Minor Cargoes, with the Incidentals representing a "partial container" cargo load that can be "shared" with other cargoes. Major Cargo would then use "double" containers to ship in 12 ton (168m³) increments.

Looking at the Subsidized Merchant deck plans (LBB S7, p20) and the 3.85 ton cargo module depicted there (3m x 3m x 6m) ... if you stretch that container to be 50% longer, you get 3m x 3m x 9m (5.78 tons) instead for a standardized incidental/minor cargo 6 ton shipping container. Major cargoes then use "double wide" containers of 3m x 6m x 9m (11.57 tons) to hold their cargo loads.

. . . . . . .

Such an interpretation of containerization then means that the standard cargo unit a shuttle would need to transport would be either 2 containers of 6 tons each, or 1 container of 12 tons ... in other words, everything ought to operate in terms of multiples of 12 tons (0.5x through 6x) for inter-modal transport via containerization to handle every type of incidental through major cargo type with maximum efficiency. Each container would classify as a 6 or 12 ton metal hull of Configuration: 4 (Close Structure) "box" shape, costing Cr360,000 per 6 ton cargo container (double that for 12 ton containers).

The most likely shuttle size for handling these cargo modules would then be a 20 ton shuttle with a 12 ton cargo bay, that has a bridge with no computer (the bridge is cheaper on Cr than a computer), leaving 4 tons left over for drives and fuel in an unarmed configuration. For armed shuttle types, you'll need 2 acceleration couches (pilot+gunner), a model/1 computer (weapons require a computer), 1 ton of fire control for the turret, leaving 5 tons remaining for drives and fuel, which could be enough to mount a pulse laser in a triple turret for a missile rack/pulse laser/sandcaster combo and still have enough EP for full Agility at all times. Minimum drive performance ought to be 2G maneuver and Agility: 1 (although 2 would be preferred) for cargo transfers from ship to shuttle to destination for loading and unloading operations.

It also means that if carrying one 1 major, 1 minor and 1 incidental cargo of maximum (1D=6 in each case) lot size each, a cargo bay would need to have 72+36+6=114 tons of available cargo space to carry them all in a single trip and require 9.5 (call it 10) tug shuttle round trips to load and unload everything.
The maximum cargo possible under LBB2.81, 11 from a population A world would be:

• 1D+6 Major cargoes
• 1D+7 Minor cargoes
• 1D Incidental cargoes

At absolute maximum capacity size for all (using the 72/36/1 containerization scheme, rather than the 60/30/1 scheme offered in LBB2.81) in which every single die roll is a 6 requires a cargo hold size of:

• 12 x 72 = 864 tons
• 13 x 36 = 468 tons
• 6 x 6 = 36 tons

864 + 468 + 36 = 1368 tons of containers (gotta load 'em all, gotta load 'em all!)

How does all of that sound? :coffeesip:

You are thinking strictly in terms of volume, not mass. When I think cargo, I think mass first, then the amount of space occupied by a long ton of 2240 pounds, slightly larger than a metric ton of 2205 pounds. Long tons are what my sources, both military and civilian, are in. For rule of thumb purposes, a long ton of rations occupies a volume of 94 cubic feet. A long ton of general ammunition occupies a volume of 40 cubic feet. The Traveller dTon can be viewed as either 13.5 cubic meters, four 1.5 X 1.5 X 1.5 meter cubes, equal to 476 cubic feet, or 14 cubic meters, equal to 494 cubic feet. So a Traveller dTon can hold slightly more than 5 long tons of rations, or 12 tons of ammunition. Steel ingots, with some dunnage to allow them to be moved easily, occupy 10 cubic feet per long ton. That would be 48 tons per Traveller dTon. Nine 500 pounds bales of moderately compressed cotton would weight 4500 pounds, slightly more than 2 lont tons, and occupy a volume of 242 cubic feet, or 4 tons of baled cotton per Traveller dTon. Feathers run 250 cubic feet per baled ton, so about 2 tons per Traveller dTon. Then standard 3 X 3 X 6 meter Traveller container will hold 8 tons of feathers (compressed bale) or 192 tons of steel ingots. That is a pretty large weight range. Then you have the material that is shipped in barrels, like wine, beer, ale, various cooking oils, motor oil, and grease. Each barrel might be a discrete shipment. but all going to the same port.

Shipping vehicles is a different story. There, the first thing to be considered is the cubic volume occupied by the vehicle, and not simply in cubic feet either. That is a multiple of length by width by height. For a Traveller cargo ship, the height is going to be the most critical dimension. That and how much weight can the deck hold per square foot or meter. A WW2 Jeep was 132 inches long, 64 inches wide, and 52 inches high with the windscreen down. The volume was 331 cubic feet for a mass of 2,453 pounds. The WW2 M3A3 medium tank was 122.5 inches high, 102 inches wide, and 223 inches long, with a total cubic volume of 1,620 cubic feet, and a weight of 62,240 pounds empty. For a volume of a little under 5 times that of the Jeep, the tank weighed over 25 times a much. Then there was the 40-passenger bus, with a cubic volume of 2,164 cubic feet and a net weight of 13,260 pounds. A 2.5 meter ceiling only gives you a clearance of 98 inches. A 3 meter ceiling gives you 118 inches, but to realistically carry a 3 meter high cargo container, you are going to need more like 3.5 meter clearance. Four meters would not be too much. Remember, you do have to move the containers on and off the ship in some manner.

I have not even considered bulk cargos of stuff like unrefined ore, grains, lumber, or liquids. Then you have this marvelous bean that yields that wonderful beverage, coffee. That can be anywhere from 57 to 75 cubic feet per ton when green, depending on the origin. That is typically shipped in sacks of about 132 or so pounds.

Personally, I am perfectly happy with the 3 X 3 X 6 meter Traveller cargo container, although it is a little bulkier than I would like. I also use a 1.5 X !.5 X 3 meter crate, one-half of a Traveller dTon, rated load of 2.5 tons, that works quit nicely for my purposes.

I should note that I paid for my college education by packing spare parts for a machinery company, so I gained a good idea of how stuff is packed and shipped, along with being in the U.S. Army Quartermaster Corps. I am a bit strange as I really like studying logistics and supply and how material is shipped, as my signature says.

 

[Condottiere]

1. In most cases, it tends to be figuring out how to take advantage of existing conditions, sort of like natural selection.

2. The breakthrough is anti gravity motors, which means that any sized cargo can be picked from practically anywhere, and delivered to practically anywhere.

3. The limitations are dependent on other aspects of the transportation network, lowest common denominator.

4. I'm sure the size of future containers would depend on what is the most practical size to move things around, compromised by the size of what they are likely to be carrying, and the most economic means of transport, which would include the transport craft, and the configuration of the container itself.

5. While I was partly joking about the container being biodegradable, generally speaking, you'd want the cheapest strongest material that will last for the preferred lifespan, that can be cheaply manufactured.

6. Weight is the consideration dirtside, volume decides motivation in the heavens.

7. I'm speculating that the two basic configurations will turn out to be Lego brick cubes and rectangles.

 

[Spinward Flow]

You are thinking strictly in terms of volume, not mass.

Because that is how the LBBs work for cargo hauling on starships.
Starship tonnage in CT is a volume constraint before it is a mass constraint.

 

[kilemall]

7. I'm speculating that the two basic configurations will turn out to be Lego brick cubes and rectangles.

Yes to the brick for the large lots, but I would put forward the tetrahedrons from Silent Running for small bulk items, I think they would work out to 1/4 dton each. Stackable both vertically and tightly packed horizontally.

For larger powders/liquids, the modern day bulktainer fitting the lego type brick form factor-

Alternatively the 1000 liter bulktainer, perfect for those TL6 E starport dropoffs. Occurs to me this is a good form factor for small package aggregation, 10-13 of these per dton.

As to the container cost, my home rule is the containers have to be made at starship hull cost for external mounting, and 1/2 the cost for internal bay use only.