RimWorld Mech Gestation Accelerator: The Processor and the Cycle Time

There is no mech gestation accelerator. Use the processor.

Players look for a gestation "accelerator" because growth vats, sleep and deathrest all have one. Mech gestation does not. There is no accelerator building. Mech Gestation Speed comes from two places only: the Crafting skill of the mechanitor running the bill, and how many mech gestation processors sit in their brain.

Mech gestation processor

Speeds up gestation. Implant, up to 6 per mechanitor. Also speeds resurrection in a gestator.

Mech booster

Does not touch gestation. Mechs within 9.9 tiles work 50% faster and move 15% faster.

Bandwidth pack

Does not touch gestation. +9 bandwidth so you can own more mechs. It also costs signal chips.

What the processor changes, and what it does not

• It shortens each 48-hour cycle, the short start job at the tank, and the final job that takes the mech out. All three use Mech Gestation Speed.
• It also shortens resurrection bills in either gestator. A revival is one cycle at the same speed.
• It does not change bandwidth, control groups, how many cycles a mech needs, ingredient cost or wastepacks.
• It does not remove the hand-off between cycles. Someone still has to start each cycle, and it must be the same mechanitor.

The other "accelerators" belong to other systems. The sleep accelerator (Ideology) is a bed facility. The deathrest accelerator (Biotech) shortens deathrest. Growth vats and Workshop "growth accelerator" mods deal with embryos and children. None of them work on mechs.

How long a mech gestation cycle takes

Every gestation recipe uses the same cycle length: 120,000 ticks, or 48 in-game hours at 100% speed. A mech needs 1 to 12 of those cycles. Cycle length is 48 hours ÷ Mech Gestation Speed:

Crafting 10 is the only row where Crafting leaves the total unchanged. Crafting 20 with six processors is 375%, not 325%, because the 1.25 Crafting factor also multiplies the +200%. Crafting 0 with six is 225%. Some older tables add the two bonuses together; those only match the game at Crafting 10. Open the mechanitor's info card and read Mech gestation speed under the Mechanitor stats to see the value in your save.

Worked examples

• Lifter (1 cycle): 48 hours at Crafting 10 with no processors. Six processors make it 16 hours, so one light gestator can turn out a lifter about once a day.
• Diabolus (12 cycles): 24 days at Crafting 10 with no processors, 8 days with six, 6.4 days at Crafting 20 with six. At Crafting 0 it is 32 days bare and 10.7 days with six.
• Centipede (6 cycles): 12 days bare at Crafting 10, 4 days with six.

Whose speed counts

The first mechanitor to start a bill is bound to it. The game reads that mechanitor's Mech Gestation Speed every tick until the mech is born. Nobody else can start later cycles on that bill; the tooltip shows "already assigned". To use your best crafter, have them start the bill. In a colony with several mechanitors, one fast mechanitor can run every gestator and hand the finished mechs over.

Installing or leveling up mid-cycle

Speed is read live, so a new processor or a Crafting level-up shortens the time left right away. Time already spent does not come back. At Crafting 10, going from zero to six processors halfway through a cycle turns the last 24 hours into 8. The inspect pane updates its "Time left this cycle" line at once.

The start job between cycles

Starting a cycle is a Smithing work job of 1,800 work, and it also scales with Mech Gestation Speed, not Global Work Speed. That is about 43 in-game minutes at 100% and about 14 minutes at 300%. Taking the finished mech out is a shorter 300-work job. The job itself is quick. The long gaps come from the tank waiting for the mechanitor to show up.

How to craft and install the mech gestation processor

1. Unlock Standard mechtech. A mechanitor studies a signal chip (0.5 hours; the chip is not used up), then researchers finish Standard mechtech. See how to get a signal chip for the summon and the drop.
2. Queue the bill at a machining table. The recipe needs a crafter with Crafting 6, 1 signal chip and 6 components, plus 3,200 work scaled by the crafter's General Labor Speed. The crafter does not have to be the mechanitor. Short on parts? See where to get components.
3. Self-install it. Select the mechanitor, right-click the processor and choose Implant mech gestation processor. It takes a second or two with no surgery and no doctor. Only a pawn with a mechlink can use it. Each extra processor raises the implant level by one. At six the menu says "max level".

A mechanitor who cannot do Smithing can wear processors but cannot gestate at all. Check this before spending chips. The mechanitor setup guide covers who should take the mechlink.

Why the mech gestator looks stuck

A gestator is a queue, not a fabrication bench. A cycle counts down by itself, but each new cycle and the final pickup are separate jobs for the bound mechanitor. Read the glow first.

A running cycle keeps counting while the bound mechanitor is off the map — for example on a caravan — as long as they are alive and not in cryptosleep. The next cycle waits for them to come home. The orange bar on the tank fills once per cycle and empties again. Use "Gestation cycles remaining" in the inspect pane to track the whole bill.

Wastepacks per mech

Waste comes out once, when the mech finishes. It equals the mech's wastepacks per recharge: 5 × its bandwidth cost. That is 5 for a lifter and 25 for a Diabolus, centurion or war queen. Revivals produce waste the same way. Plan hauling if you chain several big mechs in a row.

Which gestator, and how many cycles

The mech gestator (Basic mechtech, 150 steel + 3 components, 3×2, 350 W while gestating, 50 W idle) handles light mechs. The large mech gestator (Standard mechtech, 300 steel + 6 components, 4×3, Construction 6, 500 W / 50 W) handles everything heavier. Processors help most on the long bills in the large tank.

Resurrection works only on corpses of your own colony's mechs, and only for the types on each recipe's list: the gestatable light, medium, heavy and ultraheavy mechs above. Allied or hostile mech corpses, war urchins, termites and apocritons cannot be revived. It takes 1 cycle and no subcore, plus steel by weight class: 25 light, 50 medium, 100 heavy, 150 ultraheavy. The mech comes back at 50% energy with its injuries cleared. Light corpses go in the small gestator and the rest in the large one. Termites and apocritons have no player gestation recipe either. War urchins come from a war queen, not a gestator. Hostile mech clusters are a separate system.

Spend the signal chip on speed or on bandwidth?

1 chip → processor

About +0.33 gestation speed. Most useful when you rebuild 6- and 12-cycle mechs often.

2 chips → bandwidth pack

+9 bandwidth while worn. Also 50 steel and 8 components, Crafting 4. Lets you own more mechs.

2 chips → Diabolus bill

A friendly Diabolus costs 2 chips of its own. A player Diabolus does not drop one when it dies.

Bandwidth usually comes first. A processor cannot help you gestate a mech you have no bandwidth for, and every running bill reserves its bandwidth for the whole gestation. Get the bandwidth pack, then put spare chips into processors once rebuild time is your real limit. That point comes when a Diabolus or centipede line dies faster than it grows back, or when one mechanitor feeds several large gestators.

The first processor is worth the most. At Crafting 10 it cuts 48 hours to 36.1, saving about 12 hours per cycle. The sixth cuts 18.0 to 16.0, saving 2 hours per cycle. Two or three processors capture most of the gain for everyday light-mech work. Going to six mainly pays off on 12-cycle bills.

A second gestator often beats a processor for throughput, and it uses no chips. For Diabolus or centipede bills that means another large gestator: 300 steel, 6 components and Construction 6 (a small one is 150 steel and 3 components). Two tanks can double output only if you also have the ingredients, the bandwidth for both bills, and a mechanitor who starts each cycle on time. Processors make each cycle shorter. More tanks let cycles overlap. The mechanitor still has to visit every tank between cycles, so keep the tanks close together.

Set up a gestation bay that does not stall

Once the processors are in, most lost time comes from the tank waiting on people. Layout decides how long it waits.

• Keep the tanks close to where the mechanitor works and sleeps. Every cycle and every pickup is a walk. Several tanks side by side let one trip start more than one cycle.
• Keep the interaction spot clear. The mechanitor stands on the marked tile in front of the tank. Furniture, a wall or a forbidden door there stops the job.
• Store ingredients next to the bay. Steel, plasteel, components and subcores are hauled into the tank before the first cycle. The bill cannot start until the tank has everything, and the inspect pane counts what has arrived.
• Plan for power. A running gestator draws 350 W (large: 500 W) and 50 W idle. Cycles pause without power and resume with their progress intact. Batteries or a dedicated generator cover shortfalls and fuel gaps. They do not help during a solar flare: the flare shuts down powered buildings no matter how much stored or generated power you have, so every tank waits it out.
• Send wastepacks somewhere safe. A finished Diabolus leaves 25 wastepacks in the tank. Give haulers a waste stockpile or an atomizer route so the next bill is not blocked. See pollution cleanup for disposal options.
• Stagger long bills. Starting 12-cycle bills a few hours apart spreads the hand-offs, so the mechanitor is not needed at three tanks at the same moment.

What does not speed up mech gestation

• Global Work Speed, drugs, inspirations and Manipulation. None of these affect Mech Gestation Speed, and the start job uses gestation speed instead of work speed.
• Room quality, cleanliness and tool cabinets. Gestation bills have no workbench speed factor, and tool cabinets cannot link to a gestator.
• Mech booster and control sublinks. These raise mech work speed. They do not affect gestation.
• A higher-tier gestator. The large gestator is needed for bigger mechs. It is not faster, and a lifter cannot be gestated in it.
• Power backups. These do not speed anything up. They prevent pauses from power shortages, but not from solar flares.

Mech gestation time calculator

Pick the mech, enter the Crafting level of the mechanitor who will start the bill, and their processor count. Add how many mechs you want and how many matching gestators they can run.

Quick answers