[kolias]

I know I can do this using a piece of paper under my endmill but to be accurate to the millimeter I wonder if there is a way to do this job using the DRO's.

My tabletop cnc mill has a cutting area of 34"x46" and is all made with 3/8" aluminum plate/flatbar, 3 axis, 4 stepper motors, HY VFD and HY water cooled spindle. The tabletop is 5/8" MDF

I have a home made touch probe and a simple script and when I use the Mach3 Auto tool Zero the endmill decent and when it touches the top of my 3/8" plate it goes up by 1" and the DRO reads 1". Now if I do the same in the opposite side of the table the results will be the same but it doesn't tell me if the tabletop at that point is perfectly level in relation to the first point.

Any ideas how this can be done?

Thanks

[Superman]

Your thread title is not what you are describing.

It sounds as if you want a method to see if your spindle is trammed correctly .... that the spindle is perpendicular in both X and Y planes

Done with an indicator held by a bar in a tool holder.
Google "tramming a spindle".

The larger swing around the spindle, the more accurate.
Gauging tool lengths should be done in 1 place only, so your tools are relative to each other.

[kolias]

Thanks for the help, I know about tramming and its not what I'm after.

The cnc is brand new and haven't done any real cut yet. Since the tabletop is so large (34"x46") I was thinking how to verify if the depth of cut is equal at any place of the tabletop. I did a cut of a rectangle 1/8" deep and measuring the depth with a micrometer it shows 1/8" all along the groove. So its good.

However I was thinking since I have a probe which establishes the 0" point of the surface before I start a cut if it was possible to use the probe. Perhaps with a script which registers the point at one end and then compares that value with a new value at another point of the table?

[Superman]

Thanks for the help, I know about tramming and its not what I'm after.

The method of tramming is to set spindle perpendicular to the table....after you check the gauging positions ARE at the same zero level. So you don't tramm your spindle to a slope.

Another consequence from doing it, is to qualify the table surface is flat, that if you faced the table, it would be also be flat....

[kolias]

I will give it a try, thanks