Chris's Scaling Rules for Mekton Zeta
Written by Christopher Thomas.

The rules given in Mekton Zeta Plus for scaling are handy, but have a few oddities (especially with weight). Also, the gaming group I play with had floated the idea of additional scales (for nanobots, for miniature robots like the ones in "Panda Z", and so forth). As a result, I built this modified scaling ruleset, intended to supplement and/or supersede the one given in the MZP manual.

The changes to scales given in MZP are minor. The main value affected is weight, as the rules as-given result in very strange densities (especially at Roadstriker, Corvette, and Starship scales). Retconning weights doesn't actually affect gameplay much, as vehicle-to-vehicle interaction is usually handled with Mekton-scale numbers if combatants are at the same scale, and by roleplay if they're at different scales.

A revised table of scaling information is provided below. I hope readers find it useful.


Scale Size* Cost Weight
Starship ×100 ×500† ×100k‡
Corvette ×10 ×25† ×100
Mekton ×1 ×1 ×1
Roadstriker ÷5 ÷3 ÷100 (1T = 10kg)
Human ÷10 ÷5 ÷1000 (1T = 1kg)
Pet** ÷50 ÷30 ÷100k (1T = 10g)
Toy ÷100 ÷75 ÷1M (1T = 1g)
Micro-Toy ÷1000 ÷500 ÷1B (1T = 1mg)
Nanobot ÷1M ÷200k ÷1E (1T = 1pg)

*Absolute speed and absolute amount of damage scale by this factor too, unless otherwise noted in MZP.
**This is for smaller pets: Aibo or Robo-Raptor scale. A full-sized dog would be built with human-scale components.
†This cost scale favours large mecha. A more realistic cost, tracking mass more closely, would be ×250 for Corvette scale and ×50,000 for Starship scale.
‡For broader scale like the one given in MZP, multiply the MZP-sidebar weights by 50.


Here's an example table, scaling a typical Heavy Striker. I'm assuming that all servo spaces are filled with machinery (this isn't quite true, but is pretty close). As a result, I have 39 kills of servo, 39 kills of stuff in the servos, and 30 kills of armour, for a total of 108 kills (59 tonnes). Assuming I pay for a bit of weight efficiency to get it under 50 tonnes, I end up with about 130 cp, and about 50 tonnes (not quite, but close enough). Per the MZP errata, I'm assuming a 10-kill torso servo means this Mekton is about 15 metres high.

Scale Relative Cost* Height Weight Density**
Starship ×5 1.5km 5MT 0.12
Corvette ×2.5 150m 5kT 0.12
Mekton ×1 15m 50T 1.2
Roadstriker ×1.67 3m 500kg 1.5
Human ×2 1.5m 50kg 1.2
Pet ×1.67 30cm 0.5kg 1.5
Toy ×1.33 15cm 50g 1.2
Micro-Toy ×2 1.5cm 50mg 1.2
Nanobot ×5 15μm 50pg 1.2

*Cost factor divided by scale factor. This tells you how hard it is to build something of a given scale, more or less. Sweet spots are Mektons and Toys. Nanites and Starships are expensive.
(This isn't actually a very useful number. It isn't per-robot, and it isn't per-tonne. It is, however, how much it costs per absolute amount of damage a group of robots could do. A 10 kill mekton-scale gun costs less than 250 hits of human-scale guns.)
**This assumes the robot has the same proportions as a 2m tall, 100kg human (6'7", 220lbs). Corvettes and Starships are assumed to be mostly empty space, more like buildings than robots, as they're intended to have people and smaller robots housed within them.


As-written, the rules in MZP make it possible to very quickly and very cheaply build hordes of small robots in your garage workshop. To fix this, I've added two new rules: The upshot of the first rule is that any one-offs of a humanoid, toy, or even something the size of a car will take quite a while to build. Production only occurs quickly if you have a large number of highly-specialized tools. A fully-equipped automobile customization shop could prototype Roadstrikers in the time computed from the scaled CPs, but a basement inventor with a respectable but modest set of mechanic's tools would use the time computed using the full Mekton-scale CP value. The difference in manufacturing time is more pronounced at smaller scales: consider the amount of effort needed to make complex human- or toy-scale robots that have very small parts, using only a basement machine shop. Specialized prototyping gear exists for a reason.

The upshot of the second rule is that even if a remote control toy car costs $100 over the counter, it'll cost you a lot more than $100 to build an entirely new one from scratch, even with all necessary equipment; you'll either be machining custom parts left and right, or cannibalizing kits for many existing cars to build the prototype, or both. In higher quantities, economies of scale come into play and you can fabricate many copies of custom parts at a lower per-unit cost. A cost multiplication factor is applied to fabrication, based on the following formula:

Multiplier = sqrt( size divisor / number made )

Making 1 copy of a toy-scale device (÷100) would cost sqrt(100/1) = 10 times as much as normal. Making 25 copies, on the other hand, would only cost sqrt(100/25) = 2 times as much as normal. Making more copies than the divisor (more than 100 toys, more than 1000 micro-toys) doesn't give any benefit (the best you can do is the ordinary scaled cost).


Here's a table showing costs per unit and costs per tonne for prototyping and mass-producing small robots. Values are based on the 130cp heavy striker discussed previously:

Scale Weight
(ea) 		Cost
(ea) 		#/tonne Cost/T Full
Run 		Cost
(1-off)
Roadstriker 0.5T 43cp 2× 87cp 5 units 97cp
Human 50kg 26cp 20× 520cp 10 units 82cp
Pet 0.5kg 4.3cp 2000× 8.7kcp 50 units 31cp
Toy 50g 1.73cp 20k× 35kcp 100 units 17.3cp
Micro-Toy 50mg 0.26cp 20M× 5.2Mcp 1000 units 8.2cp
Nanobot 50pg 0.65mcp 20P× 13Tcp 1M units 0.65cp

At first glance it may seem unreasonable that making a one-off prototype robo-pet costs as much as buying a car off the showroom floor. However, this is actually pretty realistic, given that a) the pet is as complex as the car (it's a fully-functional miniature Mekton), and b) prototypes in the real world cost anywhere from 10 to 30 times as much as production models.

The complexity statement bears repeating. At 1.73cp, a store-bought toy robot is much cheaper than a car-scale robot. However, it's still not exactly in "toy" scale. In real-world money (about $1000 per cp in the campaign I play in), it's a $1700 top-of-the-line toy robot, not a $17 "Zoids" critter (or even a $170 Robo-Raptor).

Another point that bears thinking about is "cost per tonne". Individual units are individually functional and individually valuable. Weight for weight, you get a lot more individual units per tonne at small scales than at large scales. So, cost per tonne goes through the roof. The retail value of a truckload of expensive robo-toys is far more than the cost of the truck that carries them. The practical upshot of this twofold. First, out-of-scale combiners get very expensive very fast (trying to get ten thousand toys to assemble into a giant robot could be done, but would cost vastly more than just building the giant robot). Second, nano-goo is ridiculously expensive to crank out by conventional means. It's self-replicating for a reason (which of course leads to its own problems).

Enjoy!

Last updated 30 June 2010.