Scanner build (hi, I'm new)

[Occularis]

Hi everyone!
I'm new at this place, just wanted to say hello and see if anyone feels like helping me out a bit with a project I'm working on...

I'm currently in the process of building my first X-Y scanner, which will be fitted with a LPC-815 20X DVD burner diode (red 250-300mW) and a PHR-803T HD diode (Blu-ray 405nm 150mW), each mounted in Aixiz modules and fitted with modified versions of the common RKCSTR-driver circuit.
I have managed to get my hands on a couple of sweet 1.8 deg/step, 1.7" stepper motors (30ohm coils) and the C-Media CM106 USB 2.0 External Sound Card is about to be ordered.
My problem at the moment is that I have extremely limited resources (funds) for this project, and I still need 2x correction amps. I'd be happy to build them, but I cant find a proper schematic or component listing anywhere, I figured this would be the place to ask. -And no, I'm not building any of the parts or the complete scanner to sell it, it's going to be my wallets' nemesis for a long while!

[mccarrot]

Hi, welcome.

Nowadays you can get a decent 20K galvo set for less than 100 euro, so why take the effort to make a amp.

Please be careful with 0,4W power and stepper motors, at some points the beam can go very slow.

[Occularis]

I'm trying to keep the cost at an absolute minimum, that's why I'm not ordering new galvos.
The project is basically "funded" by my school (electronic engineering programme) in the way that they allow me to make all the PCB's and use whatever components I can find, to build my scanner. I managed to get them to pay for a 101 us$ order of housings and diodes (so yeah, i COULD fit 3 more Blu-rays in there, hehe), but that's their limit on the new stuff, so now i have to build the rest from scratch , any help would be greatly appreciated!

[sugeek]

http://elm-chan.org/works/vlp/report_e.html

Check elm-chan out he built his own galvos you may find the site useful.

-Adam

[Occularis]

http://elm-chan.org/works/vlp/report_e.html

Check elm-chan out he built his own galvos you may find the site useful.

-Adam

Yep, been there a bunch of times ^^. Also been all over Laserpointerforums.com, laser-man.co.uk and a lot of other places, hehe.
Although, I think I'd be better off using the stepper motors i got instead of trying to actually build new galvos. I might give it a shot just for the heck of it while i wait for my orders to arrive, but still... -Need amps =/

[MisterWilling]

Just a word of advice, every time I have tried to save money in this hobby it has cost me lots and lots of time. Some times waiting to build and saving money for the proper gear is better.
One example, I spent nearly 20-30 hours getting my correction amp and sound card controller working due to driver issues. If I had worked that at overtime in my job I could have bought Pangolin!
Heres the 5 page thread on that issue http://www.photonlexicon.com/forums/...62-Scan-Pro-40

[Doc]

Boring safety stuff

I am sure that you've heard it before but do not attempt to direct this thing towards yourself or an audience unless you incorporate a physical beam stop/shaddow mask. You only get 1 pair of eyes to last you.

Steppers are a really a poor choice for steering a laser beam at reasonable speed with any accuracy or control.

End boring stuff

However; good luck with your project and have fun with it, but be prepared to get addicted to the point of doing deals with the devil to fund your habbit

Ian

[MisterWilling]

Hes not lying, I had a $200-$300 dollar budget for my first scanner. Now I have spent $2500-$3000 and I'm not done with it. I am building a 5 color though, those damn 473's are pricey!
Good luck with your project!

[cfavreau]

Try looking up German MOT projects and Popelscan. They used really small stepper motors. If you PM me with your email address I think I have a few PDF articles on using stepper motors and their related amps which basically are audio amps. You can power up one of the coils with around 12VDC to get it to stay still and act as a damper/limiter (kind of like a torsion bar). Then you connect the amp to the other coil. A little amp goes a long way with the smaller motors. You can try just starting with a power OP-AMP or even an LM386.

Here is a link to one of the PDF's describing the setup including DAC:

http://www.ctrnd.com/NormLaserShow/G...86-prutchi.pdf

It is really simple and pretty much as described above.

Have fun!

[Occularis]

Thanks for the advices and tips guys (although I'm well aware of all the safety-stuff, hehe)
Had a rather boring day at "school" today, while I was waiting for my PCB etchings (a couple of simple LD drivers and a bunch of test-loads) to get done I found a bunch of old 120MB tape-backup units that was going to be dumped in the trash. 30 minutes later I had salvaged 12 more stepper motors (figured i might use them for filtercontrols / dichros or something in the future).

-Anyway, I'm still having a hard time finding a single-sided pcb schematic for the amps (The LM759's seem a bit... crude ). If I had the cash I would order them from DrLava in a heartbeat, unfortunately that's not the case... I'm hoping one of you might have an old schematic that works nicely with the soundcard-dac somewhere .