30 Mar
2010
30 Mar
'10
8:10 a.m.
On Mar 30, 2010, at 10:57 AM, Marvin Johnston wrote:
--
Dave McGuire
Port Charlotte, FL
I just finished a project using stepper motors and a
PIC processor
to drive the whole thing. Aside from defining the parameters (and
debugging my mistakes), it was pretty easy to do. I used a Ramsey
Stepper Motor driver kit to drive a 200 step/rev floppy disk drive
motor along with a 16F84A PIC processor to control it, and it
worked great.
Wow...PHOTOS!!!
If using a laser, what power would be required to cut
the holes and
what kind of laser? I currently have a 35W IR laser that could be
more than a bit dangerous without proper safety precautions ...
I've kind of gotten used to eyesight :)!
This is a VERY interesting idea. It depends on the spectral
absorption characteristics of the media, but as an offhand guess, I'd
say 150mW ought to do it. One of the BluRay laser diodes that are
readily available on eBay should be just fine, something like the
common PHR-803T. That does 100mW+ at 405nm.
Since the material you're drilling is so thin, you don't need a
cylindrical beam, which simplifies the optics by quite a bit. A
simple focusing lens should be fine. The only tough part is driving
the laser diode, which is only tough if you haven't handled them
before. Laser diodes like this will burn out if you look at them
crooked. Building a proper power supply isn't hard or expensive,
though.
I encourage you to investigate the possibility of a laser-based
automatic punching system for this. If you want, you may subscribe
to the lasers list that I run; there's lots of help available there.
There are some serious heavy-hitters on that mailing list, including
Winfield Hill (yes, THAT Winfield Hill) and Jon Singer (who has lased
just about everything).
-Dave