"Karl Townsend" wrote in message
anews.com...


Your laser digitizer sounds interesting. Please tell me more about it. I
do a lot of designs for my CNC plasma table by taking a photo of the part
and turning it into a .dxf file but accuracy suffers a little in the
process and I end up checking all the measurements if it is a critical
part. Artwork isn't too fussy but some of the machine and equipment parts
I do need to be right on.
Steve

I bought an Omron laser displacement sensor off eBay. It puts out 4 - 20
milliamps over distance of 1.1 to 2.0" away. I mounted it in a taper 40
holder. I then go back and forth over the part in my CNC mill and record
distances plus X,Y,Z dimensions off the control. You end up with a ton o'
points. Then the hard part, make it into something usable. So far, I'm
learning Rhino. I'm not too good at this step.

If you got time, there's also a point probe that you can build or buy.
With that you move the mill to an X,Y location and then move Z till the
probe touches; record point;repeat. Much slower and slightly less
accurate. But still way more than you'd need for a plasma cutter.

I have done this with the plasma cutting table but it works best with one
person jogging the table another marking the points on the screen. Most
parts I draw by coordinates but odd shaped stuff is a little harder to
measure and those I use the camera method. I have been using the trace
function in Corel Draw and saving it as a .dxf and it works quite well with
a high contrast photo. I had a chance to buy a digitizing table a few years
ago but didn't have the cash when I was first starting out so I passed on
it. (still don't)
Steve



I did the photo to .dxf thing with my business sign. Next time you drive
by, look at the new signs. Took more time than if i had just started over
from scratch.

I will take a look and try to stop in next time I go south of St Cloud. The
last time we were there we stopped to have lunch in Dassel at the little
cafe in town. After we stopped at your house and you weren't home I wondered
if that wasn't you in the cafe. It is fun to wonder about what some of you
guys look like. Gunner, I know he looks like a gangly hairy cowboy.
Steve