Cambridge Polymer Labs (quest)

Cambridge Polymer Labs is a side quest in Fallout 4. The point is to find chemical samples in the abandoned Cambridge Polymer labs and complete a 200 year old science experiment.

Detailed walkthrough
Upon entering the Cambridge Polymer Labs, the Sole Survivor is greeted by a Miss Nanny robot named Molly. She asks if the Sole Survivor has come to fill a job position. Answer yes and Molly will give the player character a one question survey for qualification asking whether or not the player character has any research experience. She will assign you to a job and provide a uniform (set of clothing and items) based on your answer:


 * 1) Expressing confusion: Janitor, a mop and a green mechanic jumpsuit.
 * Yes: Researcher, a lab coat and clipboard.
 * 1) "You need me" (Charisma check): Sales Coordinator if successful, a dirty tan suit and a pen. Lab Assistant if failed.
 * 2) Threaten: Security, dirty army fatigues, a stun baton, and a pair of patrolman sunglasses.

Molly will then ask if the Sole Survivor would like an orientation, which is optional. If they agree, she will move into a side room with a broken slide projector and relate the history of the company. The Sole Survivor is asked to change into suitable attire and Molly leads the player character through a changing area with sets of lockers, then to proceed to the clean room.

''Note: this is the last chance to leave and switch followers before being locked in. Curie has a significant affection boost (69 points) for completing the research, so it might be beneficial to retrieve her before moving forward.''

As soon as the Sole Survivor enters the Clean Room, Molly locks the door and informs the player character that Director Elwood has issued a mandatory overtime edict to the staff and that no one may leave the laboratory until the project has been completed. The room will then fill with high-level radiation, though Molly will decontaminate it shortly. The player character may then ask Molly questions, but her responses are generally that the player character should look at the research already done and see if it can be moved forward.

Just past the Clean Room, the player will come to a room with a terminal directly in front and a large machine called the Polymer Coating Applicator filling the right side of the room. The Terminal will have the research data of the experiment that's been performed up to this point.

To complete the project, the Sole Survivor must supply the Applicator with the reagents Lithium Hydride and Gold in addition to the radioactive material, U-238. Sitting right on the Applicator is a silver canister that contains Unidentified Sample 11317, which when inserted into the Applicator will identify it as Hydrochloric Acid. The Sole Survivor must explore the rest of the facility and find these components.

There is a door leading from the room with the Applicator out into the main atrium, which is filled with feral ghouls. Roughly 8-10 ghouls will attack at once, but once they are dead, the Sole Survivor is free to explore with only occasional interference from stragglers.

Entering the atrium there are two doors straight ahead. The storage room on the left Unidentified Sample 3111 (Lithium Hydride). The adjacent door leads to another small lab containing Unidentified Sample 413 (Gallium). In this room is a hole in the wall leading into the next lab, which contains Unidentified Sample 65 (Tungsten), a window to view into the Containment Room, which contains the U-238, and a wall-mounted Terminal that opens the Containment Room. Opening the room causes alarms to sound and a glowing one to rise out of the standing water in the Containment Room. The Containment Room can be accessed via the door on the ground floor at the bottom of the stairs, to the left of the door leading back to the Applicator room.

Up the stairs on the second level and turning around, there will be two doors at the end of walkways on either side. At the end of the left walkway is an office space in which the player will find Unidentified Sample 49 (Cobalt) sitting on a desk. Near this desk is a ramp leading into the ceiling ducts, which will grant access to the aforementioned right hand office, if you are unable to hack the Expert-level terminal at the door outside. Deal with the ghoul inhabitant, disable the tripwire and mines before they can go off on you, then look around the lab.

This is Dr. Wilfred Bergman's lab and the final reagent, Unknown Sample 611 (Gold), can be found sitting on a desk next to a Terminal. At this point, you have two options:

Option 1: Complete the experiment
With the two reagents in hand, leave the room and proceed to the opened Containment Room via the ground floor access. Defeat the glowing one, mindful of the radiation (hazmat suits should be available elsewhere in the lab) and collect the U-238 from the opposite wall. Return to the Applicator room and insert the components. Watch the polymer lining be applied to a piece of power armor, producing the Piezonucleic power armor, a unique Legendary power armor piece. Collect it on the far right and present it to Molly.

With the project completed successfully, she will unlock the Clean Room, adding that The Director will be impressed and will want to meet the Sole Survivor. Following her will lead to The Director's office on the second floor of the main entrance area. Upon opening the door, The Director, now a feral ghoul, tries to attack the Sole Survivor. Molly intervenes, re-informing The Director of company policies about assaulting co-workers before killing him with her saw arm. Once he is dead, Molly pays the Sole Survivor for their efforts (in pre-war money), apologizes on The Director's behalf and shuts herself down for good, ending the quest. The piece of power armor remains available for the Sole Survivor to use as they see fit.

Be sure to loot The Director's office and use his terminal before leaving the building.

Option 2: Override the lockdown
Alternatively, activate the terminal in Dr. Bergman's lab and access the "Facility Defense System" directory. It provides the opportunity to use the emergency override, which will open the clean room and fulfill the optional objective of finding another way out of the facility, but it also activates all defenses in the facility including turrets and Molly, which means the player will have to fight their way out of the facility.

Experiment Samples Numbers & Names

 * The Sole Survivor gets a special Piezonucleic power armor when combining U-238 with (Sample 611 Gold) and (Sample 3111 Lithium Hydride).
 * 11317 Hydrochloric Acid (base ID 0009bc88)
 * 3111 Lithium Hydride (base ID 000a50f7)
 * 413 Gallium (base ID 000a018c)
 * 49 Cobalt (base ID 000a0190)
 * 611 Gold (base ID 000a50f5)
 * 65 Tungsten (base ID 000a018e)

Experiment Samples Numbers & Names

 * The Sole Survivor gets a special Piezonucleic power armor when combining U-238 with (Sample 611 Gold) and (Sample 3111 Lithium Hydride).
 * 11317 Hydrochloric Acid (base ID 0009bc88)
 * 3111 Lithium Hydride (base ID 000a50f7)
 * 413 Gallium (base ID 000a018c)
 * 49 Cobalt (base ID 000a0190)
 * 611 Gold (base ID 000a50f5)
 * 65 Tungsten (base ID 000a018e)

Bugs

 * Rarely the player character will be unable to pick up the radioactive isotope U-238.
 * After completing the quest the player character will be stuck with the rest of the components (Gallium, Cobalt, Hydrochloric Acid and Tungsten) in their inventory. A solution is to use a companion to attempt to pick up the item in Cambridge Polymer Labs until inspect chemical reagent appears. Slowly approach the tubes and you can place multiple reagents, thus removing all quest items from inventory. Another solution on PC is delete the items through the command console, using the command.
 * After Molly shuts down when completing the quest, the quest log will mark the research portion of the quest as failed. The player will still have the Piezonucleic chest armor.
 * If the dialog with Molly is bypassed (e.g. you sneak past her or ignore her) and the terminal in the Director's office is accessed and the lockdown cancelled, the first stage of the quest will no longer be able to initiate and the only option to complete the quest will be to trigger security and kill Molly.
 * When closing the door to the containment chamber after retrieving the Uranium (e. g. to silence the alarm) your companion may get stuck in the chamber, even after opening it again, refusing any movement command through the (theoretically open) door.
 * After creating a prototype, a quest notification for "Complete the research project" may appear, but the quest stage will not be marked as completed or "greyed-out" in the Pip Boy. You can still speak to Molly (if not hostile) and proceed to the Director's office to complete the quest, but this will cause "Complete the research project" to be marked as FAILED in the quest summary in your Pip Boy.
 * It is possible to complete the quest without doing the research project. Kill the first Molly that appears, and another Molly will appear from a normally-inaccessible room. Collect the CPL Director's Key from the first Molly, unlock the Director's room on the second floor, and kill the Director, then go back and kill the second Molly. The quest will then complete.