Fabricators and You!*Updated 69564*

This guide is about which fabricators are good for which situations/starts and how good they are at doing their job(building!)

General fabricator basics

To start with is some basic knowledge about all fabricators. First off all fabricators can build all basic factories, laser towers, AA missile launchers, pelter artillery gun and basic economy structures. They can also all help construct any building that another fabricator in the same army (same colour) is building. Now that that is done let's get more specific.
When a fabricator (or factory) starts building, it will put in a certain amount of metal per second towards the building. For example a metal extractor takes 150 metal to build so a vehicle fabricator, which builds at 10 metal per second, would take 15 seconds to build it. If you make another vehicle fabricator help build it from the start then it would be 20 metal per second so it would take 7.5 seconds to build.

Commander

The Commander is the first and most efficient fabricator in the game. It builds at 30 metal per second and 1500 energy per second BUT produces 30 metal per second and 3000 energy per second. This means that the commander effectively uses no metal and produces 1500 energy even when building. Becuase of these reasons the commander should always be bulding something at all times. The one downside to the commander as a fabricator is that it's build choices are limited, only being able to build the basic factories, defensesm, economy buildings and storage.

Vehicle Fabricrators

The Vehicle fabricator is a fabricator that is made (startlingly) in the vehicle factory.
It has more health than the bot fabricator (in that it will go down in 2 hits instead of 1 so dont rely on this) and moves slower.
It also builds at 10 metal per second and costs 1k energy per second so it's average in that regard. It is also the fabricator that can build the advanced vehicle factory which makes advanced vehicle fabrictators and T2 vehicle units (vanguards, levelers and shellers).
It costs 200 metal to build so a factory can build one in 13 seconds at 100% efficiency.

Air Fabricators

Air fabricators are the fabricators of choice when expanded your economy or making secondary bases.
They build slower than other fabricators and cost more energy but make up for it by being able to quickly go where they are wanted.
They build at 9 metal per second cost 1100 energy per second so they not as efficient as any other fabricator.
They can build the advanced air factory which in addition to making an advanced air fabber can make peregrine fighter, Hornet bomber and kestrel gunship.
The air fabricator itself costs 200 metal and the air factory build at 9 metal per second so an air fabricator will take 23 seconds to build which is much longer than other fabricators and will likely need to be assisted with other fabricators to be produced in good time.
Note: I recommend making some hummingbird fighters guard them when they are expanding as enemy fighters will take them down in one hit.

Naval fabricators

Naval fabricators can only move in water and it moves very slowly. However the only other fabricator that can build in the middle of an ocean is the air fabricator so this is necessary for a medium to large naval base.
Naval fabricators build at the same pace as vehicle and bot fabricators at 10 metal per second and have the same energy cost at 1k energy per second so they could be thought of as the vehicle fabricator of the sea.
They are the only unit that can build advanced naval factories which can make the advanced naval fabricator as well as the bluebottle battleship, stingray long range missile boat with strong AA missiles.
A naval fabricator costs 100 metal to build and the naval factory build at 18 metal per second so the naval fabricator takes 11 seconds to build which makes it the fastest building fabricator at 100% efficiency with no assistance.

Bot fabricators

Bot fabricators are fast, but fragile, fabricators that are commonly used for building and expanding early game.
They have the same build and cost rates as the vehicle fabricator so there is no difference in how fast they build.
They are the only unit that can make the advanced bot factory which can produce the tough (for a bot) slammer, the sniping gil-e and the advanced combat fabricator (more on combat fabricators later).
The bot factory actually builds slower than the vehicle factory so the bot fabricator only comes out after 23 13.5 seconds. This means that you should build the bot factory early on for one reason and that's...

Combat Bot Fabricator!!!

This little gem is the key to having a rapidly expanding economy.
It does take a sizeable 720 metal to build and so will be a whole minute before being built but it is well worth the wait because it can build at a staggereing 60 metal per second for only 2k energy per second. that means it build 6 times as quickly as a normal fabricator for only twice the enrgy cost.
This does mean however that too many will put your economy way into the red so use the first one to build up your metal economy while the second is in production.
These are extremely useful in early game where rapid expansion is essential and once the economy has grown sufficiently then it be put on help factries make units for a massive boost to your army.
And yes maybe I will maybe I will marry these things :). Combat fabricators now can't help make buildings. Stoopid ubernet D':

Orbital fabricators

The orbital fabricator can be made by either the orbital launcher or an orbital factory. It is the only thing that can build on the orbital layer but units on the ground can help it build and vice versa.
It takes 6000 metal to build and the orb launcher builds at 75 metal per second so it will take 80 seconds to build from that and the orb factory builds it at 120 metal per second so it will take 50 seconds to build. the orbital fabricator can also build teleporters on the ground so they are good for flushing out a fleeing enemy on another planet.
it builds at 88 metal per second, which sounds good but everything orbital takes loads of metal to build, but it's good for helping with things on the ground, and it takes 4000 energy per second so they are quite expensive and i'd recommend only building them either just before or after you go advanced.

Conclusion

So anyway I hope this guide has been useful to you and leave a comment if i've missed anything or you want something explained.
So now your ready to build up the empire that will smash itself and the planet it's on into the enemies face just to prove a point >:D. Goodbye.

[Khan]

Combat Fabs no longer do what you have described.

[Fuzz]

No mention of Orbital Fabricators? I believe they can assist any terrestial fabricator.
Also, fabbers can help your allies. "the same army (same colour) is building." should mention aliies somewhere. Helping a Orbital Bot build a teleporter in my base has saved me once before. (100 Adv tanks waiting on the other side)

[SSG PandaRayTGAINS]

Very good explanation and summarisation, love the maths, numbers are everything.