Planet Abilene

Standard Weapons:

• Primary - Shotgun 

It is listed in the loadout menu for all of them as a Level 1 Shotgun. It fires fairly rapidly, 10 bullets per 1 ammo, every 0.6 seconds, and can deliver high damage at close range but has a high damage falloff. As the Engineer's most powerful weapon, he uses it primarily for defending his Dispenser or Teleporter and for engaging an enemy attempting to exploit a weakness in his Sentry Gun. The Pyro uses his shotgun for engaging targets unreachable by his Flamethrower and the Soldier will generally rely on the shotgun if his rockets have been expended, or to otherwise preserve rockets for when they are more needed. The shotgun is also a useful weapon to equip if the Heavy is running from point to point.

• Secondary - Pistol 

Its accuracy, while not exceptional, is superior to that of the Scattergun or Shotgun. It is useful for hitting targets at medium or long range or as a last ditch effort when the primary weapon is out of ammunition. The Pistol is very useful for destroying sticky bombs and taking out unsupervised sentry guns from outside of their range. The pistol suffers from medium damage falloff, despite being a single-projectile weapon. However, when fired at maximum speed, this weapon is formidable in the hands of an experienced player. The model for the weapon to bears a striking resemblance to the real life Walther PPK handgun. Neither the hammer or slide on the pistol model move when the gun is fired.

• Melee - Wrench 

Its primary function is the repair of dispensers, teleporters, and sentry guns, as well as being a melee weapon. In addition, while placed buildings will construct themselves, striking them with the Wrench will cause them to build twice as fast as leaving them alone. This effect stacks with each additional engineer striking the building with their Wrench during construction. The Wrench may also be used to remove the Spy's Electro Sappers, and is a formidable melee weapon. Its critical hit animation is a swing from right to left.

Because of his sentry, the Engineer has a high crit rate without dealing much damage himself. This combined with the increased melee crit rate often leads to misconceptions about the wrench and it's "unnaturally high" crit rate.

Engineer Structures:

• Sentry
  • Level 1 
    • One machine gun (fires about 2 shot/sec).
  • Level 2 
    • Two machine guns (4 shot/sec).
  • Level 3 
    • Two machine guns (4 shot/sec) and one rocket launcher (0.25 shot/sec).

• Dispenser
  • Level 1 
    • Generates 40 metal every 5 seconds. Heals ~10 HP/sec.
  • Level 2 
    • Generates 50 metal every 5 seconds. Heals ~15 HP/sec.
  • Level 3 
    • Generates 60 metal every 5 seconds. Heals ~20 HP/sec , similar to Medic's in-battle healing rate (24 HP/sec).

• Teleporter -   Enter  Exit
  • Level one: Takes 10 seconds to recharge.
  • Level two: Takes 5 seconds to recharge.
  • Level three: Takes 3 seconds to recharge.

Information Obtained from TF2-Wiki