Drill arm

The drill arm is an artificial body part that provides both the functionality of a normal arm, while also increasing Mining Speed by 160%, Deep Drilling Speed by 70%, and inflicting a -8% Moving penalty.

Acquisition

Drill arms can be crafted at a machining table once the specialized limbs research project has been completed. Note that this research requires a techprint. Each requires 60 Steel, 8 Components, 15,000 ticks (4.17 mins) of work modified by the general labor speed of the crafter, and a crafting skill of 5.

They can also be bought from Outlanders and Empire settlements, and are occasionally found installed on raiders.

The pawns that populate Mining work sites owned by an Outlander or Pirate factions, including minor factions, very commonly spawn with drill arms.

Summary

Body part

Drill arms replace the user's organic arm. They are universal and can be installed on either the left or right.

The drill arm has a part efficiency of 100%. This fully replaces the functionality of a normal arm but provides no enhancement - when coupled with the arm body part having a Manipulation importance of 50%, it results in an increase in manipulation of up to 50% when replacing a missing or totally inoperable hand or arm. Manipulation, in turn, affects a great many stats. For a full list of affected stats, see Manipulation.

Other effects

Each drill arm also provides +160% Mining Speed and a +70% Deep Drilling Speed. The effects of two installed arms stack. These bonuses apply as offsets to the base value of the stat, and are then multiplied by Global Work Speed, Skill factors and Capacity factors meaning the final increase from installing a drill arm can be significantly more than the nominal values. See those pages for details.

Each drill arm also inflicts a −8% Moving penalty. Moving, in turn, affects the following stats: Hunting Stealth, Melee Dodge Chance, Move Speed. This results in a directly proportional change to a pawn's move speed, and a penalty to melee dodge chance equivalent to losing −1.44 levels of Melee skill per arm replaced.

Combat

A drill arm replaces the natural "Fist" attack of the replaced arm with a more powerful Stab attack. How often this attack is used will depend on the other melee verbs available to the pawn, including those added by traditional melee weapons. For further details on how this system functions, see the Weapons page.

Name		Damage	DPS	AP	Damage Type
	Drill arm	13		20%	Stab

Installation

Installing the part requires 2,500 ticks (41.67 secs) of work, 2x medicine of herbal quality or better, and a Medical skill of 4.

Removing the part requires 2,000 ticks (33.33 secs) of work, 1x medicine of herbal quality or better, and has no Medical skill requirements.

If the operation fails, the part will be destroyed.

Analysis

Deep drills offer an extreme boost to mining speed. With 1 drill arm, a Mining 0 pawn mines as fast as a baseline Mining 13 pawn, and drills as fast as a Mining 7 pawn. While the drill arm disables the use of a work-enhancing bionic arm or archotech arm, if a pawn's primary job is to mine, then the drill arm offers a clear benefit. (Note that this implant does not increase Mining Yield, so your Mining 0 pawns won't get much out of any ores they mine.)

The increased mining speed can be very helpful to your colony. A fast miner can easily construct a huge mountain base. Deep drills in particular are slow to operate, so a drill arm can expedite expansion in the late-game. You might even want 2 drill arms for your dedicated miners.

This comes at a cost of movement speed. In addition to the reduced efficiency in regards to day-to-day work, installing a drill arm will hinder a pawn's performance in combat. For ranged fighters, slower movement means that kiting tactics are no longer as viable. For melee fighters, the moving penalty directly encumbers a pawn's melee dodge chance. This can be eventually compensated, partially, by using bionic legs.

Drill arms can also be used as a viable replacement for a destroyed or dysfunctional arm. There are no wooden arm replacements, and prosthetic arms are only 50% as effective as a regular arm, resulting in −25% Manipulation per arm. For comparison, the drill arm offers full Manipulation in exchange for −8% Moving, plus the bonuses to mining.

Version history

Royalty DLC Release - Added.
1.1.2565 - part efficiency 50% -> 100%, boost 180% -> 160%, movement penalty.
1.5.4062 - Now attaches at the shoulder like every other arm part, instead of the arm. Previously attaching another artificial arm on the shoulder would prevent future installations of a drill arm, since there was no more organic shoulder.

Artificial body parts