Reading a dro

Geerbangr

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I installed a dro pros magnetic scale dro on my Enco mill and as some of you guys already know I’m new to this stuff.

So my question is about reading the dro. Is there an industry standard about reading a dro or is it personal preference? Do you typically read the scale - or + in one direction or the other? Like on the x axis for example. Should the scale read - while conventional milling and + while climb milling for a nice finish?

Here’s a pic of my little rig.

hSPqd9a.jpg
 
I believe that convention is that the table moving left or spindle moving right relative to the table is positive and the table moving forward or the spindle moving back relative to the table is positive and the spindle moving down is relative to the table is negative. It doesn't matter all that much on a manual machine but it does on a CNC. My manual mill has the z axis direction reversed because of clearance issues with the pickup. The cable would have been dangling down and interfere with the work. I have used it that way for thirteen years. As I recall, some of the newer syastems allow you to reverse direction in software.

When you are milling, the readout increasing or decreasing while climb cutting depends upon whether you are milling the front side or back side of the workpiece. I remember it as follows: if the you are looking in the direction of the cut, you are climb cutting if the work is on the right side of the cutter.
 
Make it whatever you like, there is no standard thus the +- key, it allows you to make either side of 0 what you feel comfortable with.

The DRO merely gives the position of a particular part of the tool in use.
 
Typically in my experience all movement is relative to the head.,

Head moving up is +

Head moving right is + (table moving left)

Head moving away from front of machine is + (table moving towards front of machine)

You can set it up anyway you like, but when (if) you transition to other machines you may find that you will get confused and make mistakes when they are not setup like your machine.

In my opinion you should find a zero that is a good refference on your part and the center of your tool at the tip. Then go from there as needed.
 
As said it's can just be personal preference however....

Take a look at you DRO Pros manual & see if your DRO has the Arc/radius functions. If it does the manual should state how you should setup you axes directions so the Arc/radius functions will work properly. Generally it will match the same directions as a CNC machine. This also helpful if work off of CAD prints so the coordinates will match with what your DRO reads.
 
For consistency, you probably want to set it up as a right-handed coordinate system. That way the math makes sense. So that means +X is to the right, +Y is in towards the column and +Z is up.
 
This makes good sense. I’ll go with that. Thanks abunch!!


For consistency, you probably want to set it up as a right-handed coordinate system. That way the math makes sense. So that means +X is to the right, +Y is in towards the column and +Z is up.
 
Some conventions have it that the lower left corner of your work is 0, that way all figures are positive. It's your choice.
 
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