I've picked up a modified webcam for use with my Taig mill and Mach. It seems to work pretty well but the pixel the assembly rotates on is a good ways off from the crosshair in the Mach video window. Is there a way to move the crosshair ?

Ray,

I don't believe so,  you will need to adjust your camera center to correspond to the center of your spindle.  The ones I make have 3 adjusting screws for doing this.  You can tell when it is centered by rotating the spindle 180 and if it stays on the same spot it is centered.

Arnie

I've got the Attoresearch CnCam unit off eBay. Looks like the same camera in your photo folder on the yahoo group but has a different mount. In any case, the camera appears to be rotating on one pixel...the sensor and spindle are aligned. The point they are aligned to just isn't the center of the video window in Mach. The error is just along the horizontal axis so maybe it's some sort of driver issue ?

Ray,

As you describe the camera rotates around one pixel.  Does that one pixel rotate around the crosshairs in Mach3 as you rotate the spindle?  If so, as it rotates is it the same distance from the crosshairs in each quadrant?  Does your camera have adjustment for centering. 

I am guessing that if it doesn't have adjustment it may not be that good for Mach3,  the software that came with it probably will let you adjust the crosshair to compensate for the center of the camera not being concentric with the camera shaft axis/spindle axis.   

The key to the precision is being able to align the camera view axis precisely with the spindle axis,  this is easily verified  by rotation, if the target mark moves from the crosshair as you rotate it is not properly aligned.

I saw those cameras on Ebay,  it was funny just after I had found and mounted a camera that worked real good I felt really lucky because the camera I chose was so easy to mount and focused really well up close,  I was cruising ebay and saw those and discovered it looks like it was the exact same camera I used on my mount.  If you need just a new mount let me know.

Arnie

maybe post some pic's of the screen shot when you rotate.