Cheap laser show (sorta)

[GBD]

Bieng still in the process of building my first X-Y scanner, Im no where near done, need to do many things.

However, I did manage to waste some time.. I took my 1W build and a 1" wide 1" tall black PVC puck, and shined it so that the reflections of the PVC landed on a clean white wall.

If your laser is capable of 100% duty cycle, for me at least, I managed to waste about an hour watching this thing, accompanied by some surround sound and trance.

But I do recomend to use some form of good ventillation, the fumes emitted by PVC melting and such are toxic.

I took a few short clips of it: (added sound afterwards as my camera did a crappy job recording the original).


EDIT: added some pictures.

 

[jhosler]

Very nice.

 

[ElektroFreak]

Believe it or not, your cheap laser show produces a professionally used effect called "lumia". Normally it's produced by taking a round piece of mottled glass, almost any kind of surface except smooth will do, mounting it on a very slowly rotating motor and shining a laser beam through it. The result looks exactly like that... minus the toxicity.

 

[GBD]

hmm, I did not know that.

Well, I might incorporate this concept into my RGB projector when I finish it.. might.
Maybe a mirror on a stepper.. one way directs the RGB laser output to the galvos, then when switches turns on a turn table motor (which I have plenty of from microwave ovens that I gut). and directs the laser to the rotating glass.

Not really practical, but sounds fun.

EDIT: just searched the effect on youtube, that is something else alright.
I doubt I will throw it in my projector, but it is definatly on the project list.

 

[rvrh3]

did you shine it THROUGH the pvc? Im having a hard time figuring out how you sent this up

 

[GBD]

did you shine it THROUGH the pvc? Im having a hard time figuring out how you sent this up

If you where to look straight down on the shelf it was on, it will look something like this:


The PVC is just completly solid, and when you shine a powerfull laser at an angle, it will reflect away, this case you aim the reflection at a wall or something at a distance.

Really though, any thick, circular, shiny black plastic will do for this effect, I just used a solid PVC rod because thats the thing I had on hand.

Hope that clears it up a bit.

EDIT: I cant find that damn puck anywhere now... well, here is a picture of my setup now, but its still the same idea.. exept now im using the curved edge of a thick plastic bowl instead of a solid PVC rod... issue is that it burns through once in a while...

 

[Helios]

If you defocus the laser you can help to prevent this and you can change the speed at which the designs morph! Although im sure you figured that out already.

 

[GBD]

Woah Woah woah, dont overestimate me there.

I havent figured that out, if It starts to melt I just move the puck or cup sideways so that the spot diameter is streched out and larger

Okay really, the defocus/focus idea sounds better.

Taking in what Elektro said, I will make a lumia soon to replace the plastic, nothing will be melting, and no fumes, and also we can enjoy variable speed via a motor and an RGB setup.

I will definatly post pictures and video of that when I get around to it.

 

[anselm]

Heheehehe, I've been doing the exact same thing over the last few weeks,
but instead of the black PVC I've been using a rolling tobacco "pouch" which is made of
paper and wrapped in clear plastics. This plastic will melt out of shape, but without
burning, so no fumes.

The 445nm works really great for this because of its power.

I thought about making a YouTube video, but you beat me to it.
Maybe I should make a video just the same.

I want to build a proper lumia, but those 1 RPM motors are pretty expensive
The key here is the slower the better.

 

[ElektroFreak]

Goggle Check!!

yo momma says: always wear your goggles when you burn sh*t!

especially with 445s..

jus' sayin..

 

[GBD]

I want to build a proper lumia, but those 1 RPM motors are pretty expensive
The key here is the slower the better.

I got an idea which im going to do.

Me playing alot with high voltage, I often take apart alot of microwaves for thier transformer, which I either stack several for arcs or take apart and re-wind etc.

That bieng said, most microwave ovens has 5/6RPM motor, inbuild gearbox with a decent ammount of torque for its size, that 5/6RPM is derived of a gear ratio to match the frequency (60Hz for us in north america, or 6RPM, and 50Hz for 5rpm.)

build an additional gear, that will be turned by the turntable motor to about 1RPM or slower, this will be fairly cheap, and easy to set up.

yet another option (which I will do in the future) is to modify a printer stepper motor for this task, but for now Ill be using a turntable motor that is inside microwave ovens.

Also, either way, the motor requires 120V, so you dont need any special supplies to drive it.
Last time I checked, those motors are synchronous too, so Ill see if I can get it to turn at 1RPM or slower as it is with a single phase VFD I have on hand.

Goggle Check!!

yo momma says: always wear your goggles when you burn sh*t!

especially with 445s..

jus' sayin..

But.. but.. but.. How am I supposed to see the pretty light then?

I used them for the initial allingment onto the plastic, after that I put a block of wood between me and the laser, and laid back on a bed I have next to that shelf... no more glasses at that point.. wont see anything with them on.

 

[Helios]

The melting plastic effect will never be matched by the lumina although it will be alot more durable :undecided:

you dont get the "expanding vortex of space time" with a lumina wheel but it does look cool.

 

[ElektroFreak]

Lumia is all about experimenting with surface types. You can get what you describe and much more.. Some of the better lumia wheels I've seen have incorporated a few different surfaces on one disk.

 

[GBD]

Maybe I can fashion my own by heating up a small piece of glass, and using a torch to heat it evenly (so it doesnt crack) and start to make random shapes and deformations in it.

Perhaps with enough trail and error I could achive simular effects?

 

[ElektroFreak]

You can even use plexiglass for lower powered lasers.. up to about 300mW or so. It's even easier to work with than glass.

 

[anselm]

I used a soldering iron, gas lighter, hot wire,...
on one of those clear plastic "CD"s that usually come on top of a spindle of recordables.

I found the most interesting effect is when you make small but pronounced pits, close
to each other. Kinda like a very dense miniature mountain range... :crackup: