First you'll need a Laser pointer I'd suggest wicked lasers, I've been a customer for nearly two years and I LOVE their products. For this instructable I used their CORE series laser ($50) and their 125mW Pulsar ($250) and dunked BOTH in the same case with NO water damage, how cool is that?
(materials on the next page ->)
Step 1: Materials
1- buy some 3/4" shrink tube, should be in the electrical section of your local hardware store
2- velcro (3/4"-1" wide)
3- highlighter / marker of larger diameter then laser
4- hairdryer / heatgun (heatguns are faster)
6- vaseline (petroleum jelly)
7- hacksaw/ jigsaw
Step 2: Prepare the Marker
1- cut 1" from where the marker begins to round down for the point
2- remove the felt ink "cartridge"
3- cut off just before the curved part
4- cut an inch from the end of the marker
5- sand the cut edges and make sure they're flat
6- "final" product should look like the last picture
Step 3: Cut Optics
-Remove the top of the case and using some normal "scotch" (clear cheap tape) tape, mask the circle so the plastic is NOT scratched while cutting. (third picture) I'd suggest putting two or three layers to protect it.
-Cut out the circle. I used a jigsaw, but, a hacksaw will do fine, you'll have to cut it a few times to round the corners. DO NOT clamp it in a vice! (unless it has rubber grips) you will scratch the case. While you're at it, use some sand paper and smooth down the edges.
leave the tape on for the moment, we'll take it off in the next step.
Step 4: Attach Lens
*note* make SURE the glue seal between the marker and lens is AIR TIGHT!
Step 5: Velcro
Do NOT remove the sticky backing (if the velcro has it) yet.
Basically, cut the velcro a bit large and slowly trim the piece down to size so it fits perfectly in the marker piece and the ends just touch while inside. Make sure the pieces AREN'T too wide and stick out the caps, if they do, just trim them down a bit more.
Now you may glue or stick the velcro inside the caps it should be a nice smooth, snug, fit, and move on to the next step!
Step 6: Shrink Wrap!
- remove batteries from laser
- apply epoxy to the cap w/ lens around the equator of the marker piece (mid way down, don't put too much, but make SURE it's enough to get a seal!)
- slide shrinkwrap over the piece (see first and second picture) and shrink the portion over the cap down, leave the rest un-shrunk until the epoxy has dried.
- Slide your laser in (aperture side forward!) and shrink all of the piece down to the laser.
- let cool
- repeat with the other end cap (obviously have the closed side pointing out) I would suggest having the shrinkwrap hang an 1/8 of an inch over the end of the cap. This is so it seals well AND covers all the highlighter. It's a nice finishing touch that will make the laser case look that much better.
- (back on the other piece with the lens) using some more epoxy seal AROUND the outside to shut the gap between the lens and the shrink wrap.
At this point, you're done! You should have a nice seal, and should feel resistance when you try to remove the pieces, not TOO much, if you CAN'T remove the laser, heat the shrinkwrap up again, then pull out while hot. Now it's time to test it!
Step 7: Dunk!
You KNOW you have a good seal if, when pushing the rear back on, if you stop midway through the process, the pressure you've built inside should actually push the two halves apart again. (it'll feel springy)
Now it's time for a dunking! go have fun with the laser!
PS: video to be up soon...
*as a note, if you DON'T have a green laser, I'd suggest going to the laser forum at lasercommunity.com . ALWAYS ALWAYS ALWAYS research a laser before you get it! Here's the link to wickedlasers again if you want to check some out.
**posted by lasercommunity member: thecheat. If you want to chat about lasers or something, that's the best place to contact me. Just register and drop a PM.