The weapon repair kit is a consumable item that restores the condition of the player's currently-equipped weapon, similar to the alien epoxy in the Fallout 3add-on, Mothership Zeta. It can be crafted at a workbench with a Repair skill of 50.
It repairs the condition of your weapon based on your Repair skill level:
Jacobstown - in the Jacobstown lodge, take the right-hand stairs down the hall to the last room on the right side before the bathroom. It will be found on the middle shelf near some communications-electronic equipment.
One is at Jack Rabbit Springs by the skeleton and two metal poles near the pools of radiation.
The super mutant camp in the northeast corner of the map, north of The Devil's Throat. If the trait Wild Wasteland has been taken, this location is next to The One.
In a police car at the Poseidon gas station. There are also two duct tapes and a skill magazine. However, only one of these items can be grabbed, as the disturbance caused by grabbing one forces the other items to clip under the car, making them disappear. If you exit the area and return later, the clipped items may return to their normal spot.
With the Dead Money add-on you can buy these in dispensers, granted you have the dispenser code.
Component locations
A large amount of equipment needed for a weapon repair kit can be found at the gas station near Novac. However, they must be stolen.
Old Lady Gibson, located at the Gibson scrap yard (not far from Novac), sells all the components needed to create one to two kits. Her stock respawns every three days, making her a good source for the components. There is also a workbench inside the scrapyard's building to create the kits.
Dead Money In the same terminal where you find the code for the demolition charge in the Salida del Sol service route, the code for weapon repair kits can be found here. Also, there is a code for them in the police station, sitting on top of a filing cabinet. Finding this code gives a constant supply of weapon repair kits even after returning to the Mojave Wasteland, due to a Sierra Madre vending machine being located in the abandoned bunker there. Also, the dropbox in the bunker spawns 100 Sierra Madre chips and one voucher (worth 1000 chips) every three days, allowing you to buy up to 55 kits.
Old World Blues (add-on) The Book Chute, with the Mulching upgrade, will turn clipboards into duct tape and scrap metal. (One clipboard gives one duct tape and scrap metal.) Muggy can convert coffee mugs into wonderglue and the Toaster produces scrap electronics by disassembling other toasters. The only item in short supply is the wrench.
Notes
You cannot use a weapon repair kit on a weapon that is completely broken since broken weapons cannot be equipped.
If you unequip your weapon and become totally unarmed, using the repair kit will restore a little amount of your health.
When the weapon repair kit is used, the sound effect is the same as reading a skill book or magazine.
Buying the kit itself is cheaper than buying its components by one cap.
Prior to patch 1.2.0.31x, the recipe required one additional scrap metal, wonderglue, and wrench.
Bugs
xbox360ps3 Using a weapon repair kit on any weapon with a durability mod installed (such as a .357 magnum revolver with an HD cylinder) will cause the weapon's health to decrease. This is caused by a specific function (SetWeaponHealthPerc) not properly accounting for modified weapon health.
pc Using a kit to repair a weapon with a duplicate in your inventory may cause that weapon to become invisible and temporarily hidden in the inventory list, especially when it becomes fully repaired. Dropping all instances of that object will cause the invisible items to reappear.