In the Order of the Raven (building behind the Serpent statue). After using the Elevator and you enter the room with a projector, in the room with the projector look to the right for a movable bookcase. The hidden room has a Gear box.

After you first encounter crows, before leaving the building you will see a broken vending machine. A gear box is at the base of this.

After the skyrail, you need to use the sky hook to climb into a window on the upper floor. You will enter a bedroom. Look behind the dresser to the right of the bed. The box of gear is hidden there.

Next to Voxophone 18. On the metal table.

After you pass the servants area and enter the arcade, a man from Mr. Fink tells you he has something from Fink. A gear box is on the table for you.

In the tickets building, the locked room on the lower floor has a gear box.

Once you get to the two exhibits - go into The Battle of Wounded knee. Inside, on the right, is a staff store room. Go in and find the gear on a table.

Once you get to the two exhibits - go into The Boxer Rebellion. Inside, on the right, is a staff store room. Go in and find the gear on a table.

As you reach the plaza, and before using the skyrail to get back to the ticketing office - you will find a shock jockey machine on the right. Use it and it will open a gate to where the snipers were before. Go up the stairs. On a table.

After you go past the ticketing office (left) and bar (right), you will enter the building and fight a patriot. Before leaving this area, go into the Employees only room where you went before. The turret is now friendly and a gear has been left for you.

In the same room as Voxophone 33. Use the sky rail to enter the upper floor of the Hotel in the middle of the area outside the Hall of Heroes. Shock Jockey on the device to open the door.

Before leaving the yard outside the Hall of Heroes (just before using the Gondola to get to the Air Ship) go into the Toy Shop and use Shock Jockey to open hidden room.

While in the docks, go into the Employees Only door on the far side. If you haven't already triggered a fight, taking the gear will do so.

After getting back together with Elizabeth (after she rescues you with a tear - the blimp), turn around (and see Kinetoscope 22). Next to the telescope is a ship/gondola. Unlock the door and find a gear and silver bar inside.

On top of Chen Lin's shop. Next to a sniper rifle under the sign. Use the freight hooks to get up.

The Handyman you fight (before going to the club) will drop a gear box.

After you pass the projector room and Voxophone 41, you will need to unlock a cell. Unlock the cell on the opposite side (5 lock picks) to find a gear box inside.

Before leaving the club, go to the upper level. Before going though the double doors to go back up to the Plaza, go to the right and find the office. There is a Gear and safe in the office. With other supplies.

On the way to impound you will see a green barbers machine with graffiti. Gear next to it on the floor.

Next to infusion 16, in the locked room on upper floor. Hard to miss.

Just before using the elevator to go up in the factory, a gear is on the floor.

After using the elevator, go into the room on the left. There's a few fending machines inside. Behind the dollar bill machine is a gear box.

Pass the people evacuating and the fight. After picking the lock to the building, go to the right and open the freight hook tear to get on top of the wooden scaffolding. A gear up there.

Inside the Salty Oyster, on the floor (head to the right when entering).

Near Voxophone 55. In the Founders Bookstore. On the counter on the upper level.

After fighting in the outside, the Handyman you just killed should have dropped a gear.

In the area with the snipers. After Voxophone 59, continue down the street and go into the building on the left which needs 3 lock picks. Go up the stairs to find the gear.

Next to Voxophone 60. On the upper level before reaching the Comstock gate is a shop that needs unlocking.

In the Memorial Gardens. Light the urns hanging on the outside of the moselem with devils kiss to find the hidden Gear.

Outside of the Lutece Lab is a Freight Hook tear. Below this tear is a locked shop. Unlock the shop and find the Gear inside.

While going though the Bank, you will go though a safety deposit box room just before dropping though the broken hall to reach the tear. To the far end is a corpse and a metal tub. Gear in the tub.

From the bank floor, looking at the big vault door, take a left. While going to unlock the hidden room for Infusion 23 and Voxophone 68, you will come across a room with big double doors. Inside that room. Gear next to a corpse under a big painting of a happy family.

Just behind the fourth Boy of Silence. You should see it on a metal table behind the BoS. Continue around the wall to find Voxophone 72.

In the room with the second projector and Voxophone 73. In front of the stairs is a desk with a Gear.

Second level of the airship. After Voxophone 78, there is another room past engineering. At the front of the ship, marked Secure Area. Pick the lock. Gear inside.