i'm thinking of either purchasing or building a small portable little laser that runs off batteries that gets hot enough to burn through at least plastic and hard cardboard relatively quickly.

any advice?

How the fuck would that be a welder?

You can build one that will melt through darker colored plastics at an OK rate with the diode from a dvd burner. you won't get any "welding" type action though... just splotchy burn-throughs and almost-burn-throughs and you'll have to go and finish separating it by hand. cardboard however is t3h l33t weldable i think they're planning to use it for the front end heat shield on the next space shuttle.

If you do build one w/ a dvd burner diode, follow the instructions that are longer and more unpleasant. the ones that say you can just hook the diode straight to a battery are giving you instructions to build a laser pointer that'll go for 5 to 10 hours, then the diode burns out because that's not how to do it.

if you get the components together (by some unexplicable means) to build a laser welder, have as much fun with it as you can before you're arrested for discharging a dangerous weapon in public. on second thought just build 15 or 20 of em and get a laser militia together and you should be able to fight off all the cops in your metro area and even a decent portion of the army if you guys are good shots.



ok i think a few lines in the first paragraph are real trying to help and a few in the 2nd are too and the rest im just being a waste of space lol. i don't like being the guy who says it, but use the search function... there really are quite a few threads about building higher power laser pointers, not to mention LOTS of how-to pages findable w/google (remember, if it seems like itd be easy to do, its a shortcut and fun timewill also be cut short)