MAD SCIENTIST Cryogenic laser mayhem extravaganzaaaa :)

[themadscientist]

Hey guys sorry this is my first post but i just found the forums and this is really my first laser project so here it goes!

first off i'm a dental student with a degree in microbiology but i looove physical science gadgets physics astronomy etc.. so im a newb but a newb with a passion for this stuff

im dressing as a mad scientist for halloween and this project has been months in the making but its crunch time now and i need some last minute help/confirmation what i am doing is correct in regards to laser wiring

im wiring 10 lasers together to run off one switch and power supply so far i have modified the lasers and soldered in leads to the +/- terminals and all 10 lasers are linked in parallel (the lasers are "ebay special" chinese green <5mw lasers)

I made a couple 3v battery packs by running 3 CR123 3v batterys also in a parallel circuit

so heres where the question is the (-) laser terminals are going to get ran directly from lasers to battery and the (+) laser terminal is going to run to a momentary switch of some sort then to the (+) terminal on the battery pack....should there be any sort of resistor??? Any recommendations on momentary switches that are readily availible @ radio shack etc??? any recommendations in general???

Thanks in advance :thanks::thanks::lasergun:

 

[djayz]

Wow , a dentist.. i thought im the only one related to healthsciences.... and sorry i dont know if im sure about answering your question so i'll let the pro's to answer what your asking but i might be looking forward for your project, do post the photos

 

[themadscientist]

hey Djayz! haha ya i'm pretty random with the things i do (I actually DJ quite a bit too i have a set of numark NS7's that eat up more then their fair share of my study time haha) i love working with my hands and the abstract art/sculpting side of dentistry but this bookwork is gonna be the end of me i swear haha....and i will i will! i wasnt planning on putting too much on here b/c i want to wear it at my first san diego comic con next year but oh well its all for fun anyhow

this is all home made in my shop & my own idea/mad scientist creation lol but if you look at the black cylinder the lasers are attached to it looks oddly enough like a flow nozzle for a liquid CO2 fire extinguisher yah? one that may or may not be hooked up to a high pressure liquid CO2 tank on a custom leather harness to put on my back.... but ill never telll muahahahaha :lasergun::lasergun::lasergun:

 

[djayz]

Hahahahha.. You Sir seriously did quite a mad-invention with something that resembles laser smiley is using in your above comment XD i hope it dont burn people to ashes XD
____and i agree with the bookwork.. i never studied, cheated once and got a scholarship , now im a pharmacist

 

[Nocturnal]

You should shouldn't need a resistor, hopefully the cr123's can give enough current and last long enough.

 

[themadscientist]

You should need a resistor, hopefully the cr123's can give enough current and last long enough.

ahh bummer so i do need a resister? any idea on what ohm resister i should place in the circuit and where?

...and ya i hope they last i made 2 packs with 3 cells a piece out of energizer photo lithium cr123 (cant find a mAh rating on them).... but usually expensive lil buggers that i got a while back for free so hopefully they are up to the task

 

[Nocturnal]

oh soo sorry, I meant to write shouldn't, my bad hahaha
You don't need a resistor, along as each laser gets 3v, they have a driver to control the current

Chris

 

[themadscientist]

oh ok awesome!! thanks for the help :thanks:

 

[Nocturnal]

no problem, good luck with it all

 

[Ablaze]

You don't need a resister if you match voltages.

However, I am working on a project that is similar (in that it uses many smaller lasers) and I have used ebay lasers in the past and I can tell you this:

Since your lasers are made cheaply there will be small variations in the amount of current they pull. This will cause some to go out while others stay bright when your battery starts running low.

You can put a resister on there without messing up the circuity. If you use a small (couple oham) resister in front of each laser it will balance the draw and make them all go dim together as you start to run out of power.

Best of luck!

 

[Cyparagon]

They are constant current drivers. Putting a small resistor in there won't change the current

 

[Ablaze]

The situation changes when there isn't enough juice to work on all the lasers. Yes, you can change the batteries, but one of the more subtle signs of a good build is how gracefully it fails. Irregardless of theory, a small resister has worked for me in the past.

Another thing a resister can do is help protect against electrostatic noise in the power input, which will happen when you're wearing these. Depending on how well built your lasers are noise in the power line may or may not effect your electronics. I do suggest you have a few extra lasers handy to provide replacements if (read: when) the ones you have installed fail.

As for switches: You probably don't have the time to make this work before Halloween, but I suggest you look online for a reed switch. These are magnetically sensitive switches.You can get them as normally open or normally closed.

If you get a NC version you can put a magnet inside a cork or something and stop up the top of your chamber with that cork. You attach the reed switch to the top of your chamber. This way the device will be off until you take out the cork, but when you do the whole thing will light up and start going.

 

[Cyparagon]

Another thing a resister can do is help protect against electrostatic noise in the power input

Are you new to this electrickery thing?

1. Batteries are not electrically "noisy."
2. Noise is kind of the opposite of electrostatic. Static means not moving.
3. Resistors do a VERY poor job of protecting against noise or static electricity.

Irregardless of theory,

I jest

 

[weeba2kv]

Why are you calling yourself a "MAD SCIENTIST" if your juts stucking a few cheapass 10mW dumb laserpointers to a empty coce bottle ???



BTW : don't stick to many cells parralel... they can catch fire if the difference is to much . enjoy your build

 

[bennett326]

Why are you calling yourself a "MAD SCIENTIST" if your juts stucking a few cheapass 10mW dumb laserpointers to a empty coce bottle ???

are you trolling or just very confused ?

he is dressing as a mad scientist for Halloween and this is part of his costume. he clearly states this in his original post :shhh:

 

[weeba2kv]

ok i was just very confused