Newbie cuts wood, feels empowered...

["Dean L. Hedin" <dhedin-at-vsi.net>]

I cut the NIST logo!  Feels like a "right of passage"
or something.   Thanks to all that assisted me in this endevour. 

BTW, For any other newbies out there, steppers are sloooow.
Probably took about 8-10 minutes to cut that little logo.  
For my steppers, 
MAX_VELOCITY = 0.05 and 
INPUT_SCALE = 1920  (steps / inch )

My steppers start loosing it at about 0.08

The steppers are NEMA 34  5V 1.25 amp driving 5/8"x11 lead screws.
I am using the UMC5804 and I am driving the steppers directly 
from this chip.  The motors will take 1.4 amps but the driver will only
handle 1.25 amps so I have installed current limiting resistors (and 
heatsinks, and a fan...)

None-the-less, the wood cut cleanly (soft pine) and I don't think that
I would want to go much faster while cutting hardwoods which is what
I am shooting for.  So for now everything is fine.  Maybe later I will
install some FETS so I can drive the motors at full current.

That emc.ini file was a bugger.  Took some head scratching to 
get the axis/homing/limits etc..worked out.

Anyway..for those interested here's the pics of my home-brew router mill...

http://web.starlinx.com/dhedin/dcp00462.jpg
http://web.starlinx.com/dhedin/dcp00463.jpg

OK Ray. I'm now ready to start probing.  

Had another brainstorm.  Virtual probing.
At work I've been playing around with OpenGL.  Here's what I was thinking:

1) There is some open sourced code to read in VRML 3d models into
OpenGL display lists.
2) Create a cylinder inside of the "scene" that represents the tool bit.
3) Move this virtual tool across the model just like probing as we discussed 
before.
4) Each iteration as you move the tool, perform a brute force, polygon 
intersection test between the model's polygons and every polygon comprising 
the cylinder.  Each time the tool hits, store the coordinates.
5) Once you have a sectional slice of the model, (and you know the section of 
the unworked piece) it should be easy to derive multiple tool paths to 
whittle it down a little at a time.

The idea here would be to allow one to import VRML files into G-code.  Should
work for simple models that are not to complex.  May take some time to 
calculate but heck, processing power is pretty cheap and it would go faster
than "real" probing.

If you check out www.3dcafe.com they have a whole bunch of free models.
Or maybe do it just  to take advantage of open-source 3d editors?

Oh well, gotta walk before I can run.  Maybe I should just break down and
buy a decent CAM package :)

BTW, are any of you folks out there using machinable wax to test out your 
g-code?  I was thinking of other alternatives like some kind of cheap foam.

One more item..  Is there anyway to make the EMC gui fit on a 640x480 desktop?
If possible, it might be wise to set up the BDI to default to this as many 
are using old equipment for controllers.