laser engraving was Re:Smart Box / Dumb Box

ballendo wrote:

> Wally wrote:
> <snip>Hi Greg, I have some interist in laser engraving. A friend

of

> >mine is trying to build a Co2 laser and we wanted to do some
> >engraving and cutting with it.
> >What software are you talking about. Do you have any other info
> >that would be of help.


> Ballendo wrote:
> I'm not Greg but do have something to add. Commercial laser

engraving

> systems 'tie' the power level of the laser to the feedrate. This is
> so you don't 'burn wider' when you slow down at curves/ corners.

Much

> of our lower end CNC software will not have provisions for this.
>
> You could add a circuit that sits between the stepper pulse output
> and the machine. It would pass the pulses through (for the motor
> drives) and use the RATE(s) of the XY to determine a suitable

setting

> for the laser.
>

Wally K. replys:

Good thing you mentioned these things, i was not aware of them. Do
you think the constant velosity cutting rate of EMC would solve the
burning problem. And dosn't Yagers CNC Pro have this feature.

> ballendo wrote:
> Of course if you are writing your own control, you would do this in
> the S/W.
>
> Many years back, I built a Co2 laser (from resource unlimited

plans,

> the LC5). It worked ok, but was a bear to operate/maintain. I sure
> like the sealed tube synrad lasers when there's work to be done!

MUCH

> more expensive, but reliable as the Sun. YMMV.
>
> Hope this helps.
>
> Ballendo
>
> P.S. nowadays you can sometimes find older Co2 laser tubes, and
> sometimes the whole thing, through the surplus market. These will
> often be old medical lasers in the 10-50 watt range. OK for plastic
> and wood.

Wally K. replys

I tend to agree with you about buying a sealed laser but my friend is
obsessed with building them. He even makes his own parabolic mirrors
and has them in working Co2 lasers.