I finally figured out the solution to some of the various inconsistencies in Bender’s metallurgical and mechanical properties.
Firstly, in “Crimes of the Hot,” it is shown that Professor Farnsworth developed the prototype robot that is a direct technological ancestor to Bender, so we can assume that any technology the Professor is competent with can also be assumed to be possibly included in Bender’s design.
In “Parasites Lost,” the Professor was capable of building nanobots smaller than human cells. Therefore, much of my theory rests on the assumption that one of Bender’s most important non-mentioned features is a highly advanced nano-reconfiguration system. This nano-reconfiguration system (or NRCFG for short) is capable of rapidly reordering matter at an atomic level, creating new systems, and repairing or reconfiguring existing systems.
In several Episodes, Bender appeared to grow new switches, knobs, access panels, outlets, etc… For example, in “Hell Is Other Robots,” Bender had a previously unseen plug resembling a speaker jack on his head which he used to connected to a narcotic electricity source, and in “The Deep South,” bender has a volume knob which is never seen again. These are created by the NRCFG, and his external casing is reconfigured to accommodate them. In “The Honking,” the NRCFG was the target of the Werecar computer virus, causing Bender to reconfigure uncontrollably.
The NRCFG is also capable of repairing Bender as needed. This is evident in “Raging Bender” and “Godfellas,” wherein both episodes, he was damaged to the point of having hole in his head, and both injuries were fixed by the next scene, when he would have no time to have them repaired any other way. Similarly, other damage is rapidly repaired as seen in “I Second That Emotion,” “A Tale of Two Santas,” to name a few occasions. The NRCFG is also the cause of Bender’s seemingly miraculous recovery in “Bendin’ in the Wind.” The damage caused by the can opener in that episode was extensive, damaging the NRCFG controller in addition to Bender’s hydraulics and outer casing. During that episode, the NRCFG was working at diminished capacity, first focusing on repairing itself, before fixing Bender’s hydraulics. This is why it took so much longer to repair than in other instances.
Bender’s metallurgical composition often changes from episode to episode. It is at different times referenced as comprised of 30% iron, 40% titanium, 40% zinc, and 40% Dolomite, an unknown amount of Osmium, as well as having a .04% Nickel impurity. This is also an effect of the NRCFG. The NRCFG gathers raw material from multiple available sources when repairing Bender, so his composition is never the same at any given point. Each time his composition is mentioned, it is referring to Bender’s makeup at that specific point. Therefore, each listed amount is accurate, but the information can only be said to be accurate at the time it is given.
Bender frequently is shown to have objects stored in his chest cavity that are to large to fit inside Bender, either collectively or combined, and his internal mechanical structure is never visible when his chest door is open. In “The 30% Iron Chef,” the fact that Professor Farnsworth installed a wormhole in his table is proof that he has a mastery of quantum physics (including faster than light space travel, possibly made possible by research in the same vein as the wormhole). Adding this skill to his robotics development process, the simplest explanation to Bender’s apparent use of hammerspace is that he has a stable wormhole mounted directly behind his chest door, which acts as a gateway to a non-local storage location. In this location, Bender can store his vast riches and favorite possessions (such as pianos, the contents of public swimming pools, or the preserved head of Lucy Liu). This wormhole is mounted in front of his internal mechanical elements, hiding them from view when his chest door is open (though they are still visible by F-Ray as seen in “Fry and the Slurm Factory”).
One last simple solution – Bender’s primary control circuitry is in his head, but his body parts are not wired directly to it. His arms, legs, and torso are all controlled by a wireless conection to his central processors. This way, his arms and body can be fully operated even when disconnected from his head.
Note to self: Stop watching Futurama at 3:00 in the morning when your brain has been running purely on refined sugars.