The nerf nite finder is pretty good - its easily moddable, and relatively cheap. However the targetting light is... pathetic? Anemic? Useless?

So I found a cheap laser module and here's how it fits...

Step 1: Get the Parts

You'll require a nerf gun to modify, and a laser module to install. I got my laser from
http://www.dealextreme.com/p/2-5mw-dot-laser-module-3v-46391
Its a 3 volt module, so I could reuse the pair of AA batteries already in the toy.

DX also has laser modules with a cross shape, and a line. However I figured the dot would be best.
Be wary of 3.7 volt modules on the site, they might not even lase on 3.0V

Tools
- Small Philips screw driver to undo the case screws
- Side cutters to cut and strip wire
- Soldering iron etc for joining wires, could just twist wires together.
- Tape or heatshrink to insulate joint
- Hot Glue Gun and glue, to fasten wires and module in
- knife or dremel to trim tube

Step 2: Open the Casing

First thing is to take the batteries out. There's one screw in the butt of the handgrip. Take it out

Then there are ~14 screws - take them all out. Be careful to not strip any screwheads.

Gently lift the top off. All the internals should stay on the other side (left side)

The black tube is the bit that gets removed, to undo the two screws holding that in and remove. Then cut both wires.

* Note, now is an excellent time to do an air restrictor removal, and to give the mainspring a tweakup. There are several good instructables on this already.

The lens in front of the LED needs to come out too - if its left then the laser gets defocused and doesn't have a nice point.
So undo the three screws in the grey plastic, pop out the lens and two orange squares, and then reassemble.

Step 3: Wire the Laser

My laser package was cabled correctly, so all I had to do was strip the ends, solder or twist them, then insulate with tape or heat shrink.

You could use a bit less wire than I did, but there's heaps of space inside the case . Or you could solder the new laser straight to the existing mounts, but I was worried about melting the plastic case.

Step 4: Mount the Laser

Firstly remove the LED. Simply cut the two plastic rivetts (mushrooms) on the back of the tiny LED board, then it pops off.

This bit could have been done better.... The laser module's outside diameter is about the same as the black tube. It would have been tidier if the laser fitted up inside the tube, but it was not to be.

So I elected to carve off some plastic until the laser was in place, but retaining the two screw mountings and the strength webs.

What I should have done is cut the tube off cleanly between the screw mountings. and then used hot glue to support the module.
Hindsight is wonderful.

Finally, this was when I focussed the laser. The module has a little knurled ring around the aperture, and twisting it changes the image from a tight dot close / messy blot at a distance to the opposite. I figured a tight dot at a distance would be better, so mine's almost tightened up.

Step 5: Stick It Down

Here's messy - I used a cheap 25W hot glue gun to fasten the wires out of the way, and to pack around the laser module providing support.

Not sure if the heat from the laser module will cause the hot glue to soften over time.... will find out.

Step 6: Reassemble and Test

Put the top back in place, refasten all screws but don't over-tighten them.

I suppose I'd better put some warnings here....
1) Its a laser. Don't look into it.
2) Its a laser. Don't use it as the primary weapon... its for targetting only.
3) Its a laser. Good luck getting this into Australia or anywhere that has draconian laser wattage restrictions
4) Its a laser. Aeroplanes, helicopters, airports, police/military personnel or their vehicles or buildings are right out.
5) Its a laser. Don't use it as a cat toy cos eventually you'll shoot a nerf dart at the poor moggie.
Plus whatever other common-sense you haven't acquired in your journey through life to date.