hi all, I've been lurking and reading about DX lasers for a couple months now (I have a 30mw new wish) I just saw this yesterday: http://www.metacafe.com/watch/763506/laser_projector_you_can_take_anywhere/
if you dont want to watch it, it's two tiny dc motors with a mirror mounted perpendicular on the shaft.
I'm completely guessing how it works, I think it gets kind of a galvo effect completely from wobble of the mirrror from being a not quite perpendicular to the shaft or maybe just by vibration from the motors. if those mirrors were mounted perfectly and not vibrating, it'd just be a regular laser-pointer dot coming out the front I think.
I'm starting to build something like it. so far I've got a mirror on one motor pretty much. I wired that motor up to batteries and a rheostat and turned it on, I guess it's wobbling just right because it projects a perfect 14" or so circle on the wall 15 feet away.
mine's going to be different than his in a few ways
I'm going to use a bigger box or platform for the motors to make it easier to work on and tweak.
I have glass mirrors instead of "plastic mirrors from ebay" mine are certainly not any optical quality stuff, but probably a little better, and easier to work with I think. they came from the crafts section of walmart. $1.50 for a fat ounce-baggie of little round mirrors ranging from about 3/8" to 3/4" I think they're made for ladies to sew on to things for decoration or something.
I'm going to use two pots to control the speed of both motors independently instead of controlling the speed of just one like he did. I'm guessing but I may be completely wrong that I can get some different patterns this way.
I'm going to use a bigger box than him for another reason, that is, mounting the motor/mirrors farther apart. I think this might make it project wider up close like on a wall. I'm going to make the second motors position adjustable so I can move it up close to the first to get a tighter projection for farther away. (would this put a pattern up on low clouds? that'd be so awesome)
I'm thinking the way I'll make that second motor adjustable is cutting some slots on both sides of motor #2 in the platform the motors are on and have a hose clamp going through the slots and around the motor, to move the motor loosen the hose clamp and slide it towards or away from motor #1.
Right now for simplicity I'm leaning towards making a platform/deck/board whatever instead of a box, out of plywood or lexan about 5"x5" with a 6" long "finger" coming out of one corner that the laser pointer could be hose-clamped or velcro-strapped to. (shaped kinda like oklahoma) and then making some kind of enclosure to go around the motors and mirrors.
Mounting mirrors to the motors: I super-glued one like he did just to play around on my lunch break, would JB-weld be any better? the mirrors i"m using are are regular glass mirrors with that dull gray chalkboard type crap on the back, my motors have a little 3/32" or so metal gear. I superglued the mirror to the gear and in playing with it rev'ed the motor up all they way to its peak (the package said 5000 rpm) without the mirror flying off but I don't think it would last long at high speed.
I've got a little box I'm going to put the batterys, power switch and rheostats in and I guess that box will stick somewhere on this contraption.
one more question, I'm not completely planning on it now, but if I make my 30mw new wish somewhat a permanent part of this thing, I'd like to run it off of the same batteries that power the motors and turn on and off with the same power switch, I'm using 3 AA nimhs. Is 3.6v ok to go into that laser? I know it doesn't work very good on 2 AAA nimhs, it's very 5mw-ish looking, I have to use alkalines (haven't tried lithiums yet)
so anyone have any advice, criticism, new things I haven't though of?
if you dont want to watch it, it's two tiny dc motors with a mirror mounted perpendicular on the shaft.
I'm completely guessing how it works, I think it gets kind of a galvo effect completely from wobble of the mirrror from being a not quite perpendicular to the shaft or maybe just by vibration from the motors. if those mirrors were mounted perfectly and not vibrating, it'd just be a regular laser-pointer dot coming out the front I think.
I'm starting to build something like it. so far I've got a mirror on one motor pretty much. I wired that motor up to batteries and a rheostat and turned it on, I guess it's wobbling just right because it projects a perfect 14" or so circle on the wall 15 feet away.
mine's going to be different than his in a few ways
I'm going to use a bigger box or platform for the motors to make it easier to work on and tweak.
I have glass mirrors instead of "plastic mirrors from ebay" mine are certainly not any optical quality stuff, but probably a little better, and easier to work with I think. they came from the crafts section of walmart. $1.50 for a fat ounce-baggie of little round mirrors ranging from about 3/8" to 3/4" I think they're made for ladies to sew on to things for decoration or something.
I'm going to use two pots to control the speed of both motors independently instead of controlling the speed of just one like he did. I'm guessing but I may be completely wrong that I can get some different patterns this way.
I'm going to use a bigger box than him for another reason, that is, mounting the motor/mirrors farther apart. I think this might make it project wider up close like on a wall. I'm going to make the second motors position adjustable so I can move it up close to the first to get a tighter projection for farther away. (would this put a pattern up on low clouds? that'd be so awesome)
I'm thinking the way I'll make that second motor adjustable is cutting some slots on both sides of motor #2 in the platform the motors are on and have a hose clamp going through the slots and around the motor, to move the motor loosen the hose clamp and slide it towards or away from motor #1.
Right now for simplicity I'm leaning towards making a platform/deck/board whatever instead of a box, out of plywood or lexan about 5"x5" with a 6" long "finger" coming out of one corner that the laser pointer could be hose-clamped or velcro-strapped to. (shaped kinda like oklahoma) and then making some kind of enclosure to go around the motors and mirrors.
Mounting mirrors to the motors: I super-glued one like he did just to play around on my lunch break, would JB-weld be any better? the mirrors i"m using are are regular glass mirrors with that dull gray chalkboard type crap on the back, my motors have a little 3/32" or so metal gear. I superglued the mirror to the gear and in playing with it rev'ed the motor up all they way to its peak (the package said 5000 rpm) without the mirror flying off but I don't think it would last long at high speed.
I've got a little box I'm going to put the batterys, power switch and rheostats in and I guess that box will stick somewhere on this contraption.
one more question, I'm not completely planning on it now, but if I make my 30mw new wish somewhat a permanent part of this thing, I'd like to run it off of the same batteries that power the motors and turn on and off with the same power switch, I'm using 3 AA nimhs. Is 3.6v ok to go into that laser? I know it doesn't work very good on 2 AAA nimhs, it's very 5mw-ish looking, I have to use alkalines (haven't tried lithiums yet)
so anyone have any advice, criticism, new things I haven't though of?
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