Datum Align

You can use the Datum Align tab to select datum points on the align model, then match them to the same datum points on the reference model. CopyCAD transforms the alignment model to match the reference model. The current deviation from the original model is displayed in the Status bar.

You can define up to fourteen datums, which are identified by a coloured marker on the screen. This makes it easier to match the datums on the alignment and reference models.

The table below shows the colours used to identify the datums.

1	2	3	4	5	6	7	8	9	10	11	12	13	14

To examine the models and work out which features to match as datums, you may find it useful to use the Manual Align strategy to position the models side by side and to rotate or move the models. For more details, click here.

To use datums to align two models:

1. With both models open and displayed in the CopyCAD Explorer, click on the Model Editing button on the main toolbar.
   
   
2. Click on the Align Models button on the side toolbar.

In the Align Models dialog box, the Datum Align tab is displayed by default.

3. Click on the Alignment model list box at the top of the tab. This displays a list of the open models in this session. Click on the model you want to move.
   
   
4. Next, select the model you want to align to: click on the Reference model list box at the bottom of the tab and select the reference model.

CopyCAD selects this model, making it the active model in the Graphics window. The alignment model is also displayed.

Note: You can change the entities displayed on screen using the Draw buttons, , , and .

5. If you cannot see both models clearly, click on the Position alongside reference model button. This makes it easier to see which datums need to be picked.

You can now start defining the datums.

6. Click on the Define alignment datum button to tell CopyCAD that you want to pick a datum on the alignment model.

The list box to the right becomes active, and contains the number 1. This means that you can now define the first datum on the alignment model.

7. In the Graphics Window, select the first datum point on the alignment model as follows:
   • If you want to use a single point, click on it, then click on the Point button
     
     
   • If you want to use the point that is at the centre of a tooling ball sphere, click and drag to select a group of points on the top of the tooling ball, then click on the Sphere button . The point selected will be at the centre of the sphere. The example below shows the picked points over the top of a sphere and the marker showing the selected datum feature.

Pick these points…	… to select the centre of the sphere as the first datum

When you click on the or the , the Define alignment datum box updates by 1. So when you have defined the first datum, the box will display 2, ready for you to define the second datum.

Note: If you want to delete the last-defined datum so that you can redefine it, click on the Undo button, .

8. Now select the matching datum on the reference model:
   • Click on the Define reference datum button in the Reference model area.The list box contains the number 1, showing that you can now define the first reference datum.
     
     
   • In the Graphics Window, select the first datum point on the alignment model, using the same method as for the alignment datum.

Important: Make sure that you match the correct datums on the two models. The colour coding of the datum markers will help you.

9. Repeat these steps to define three or more datum points on the alignment and reference models.

Note: If you want to redefine a datum, select its number in the alignment model or reference model's Define datum list box, then select it again in the Graphics window.

10. When you have defined the datums that you want to match, click on Apply to move the alignment model.
    
    
11. Click on the Accept button to close the Align Models dialog box.

More:

Align Model - Overview