Help with basic alignemt

[[Ri...]]

I am trying to follow the instructional materials provided for an alignment, but I keep repeatedly running into a brick wall.

Despite following what I believe to be a pretty basic example, at the end of my base alignment the information doesn't match the info shown by my trihedron.

I am following the example below as it closely matches my part.
It has a central cylinder as it spatial and a circle located at the 12 O'clock position to clock to serve as the planar rotation just like my part.

(The only difference is that my central cylinder will be aligned to +X not +Y as shown in the example below.)

Now just to confirm some basic facts before moving on... If I'm standing directly in front of the surface plate, does the CMMs machine coordinate system follows the right hand rule? I ask because what I'm seeing is something else.


I have a part fixtured up on the machine as shown below.
Using Position# 3 the stylii points to +X



I am setting my base alignment as shown below,
Cylinder 1 is the central inside diameter.
Circle 1 is a circle at 12 O'clock, Z+ to the central bore.
Plane1 to provide my X origin.




If the right hand rule applies, then why does my spatial vector demand that it be -X and not +X, as expected?

In the example provided in the first picture the part is aligned with Y, and its spatial is +Y as expected. I am not understanding why base alignment doesn't respect the right hand rule like the example? It is most certainly aligned along +X and not -X!



View from -X


I've tried this a dozen times a dozen different ways and everytime I end up with odd result or incorrect vector direction
I need setting straight! What am I not seeing here?

[[Mi...]]

Keep in mind that each feature you create has its own coordinate system. When you define the cylinder, Calypso chooses a direction to assign as "positive". I have no idea how it chooses which way, but in this case, it assigned the "positive" end as toward the large flange. Then when you define your base alignment, to satisfy the right-hand rule, Calypso aligns the cylinder's axis against the base alignment axis. Since the cylinder's positive direction points in the base alignment's negative direction, it assigns it the "-x" direction in the base alignment window.

All this doesn't really affect anything, but if you really want to change it, you can open the cylinder feature and flip the axis direction manually. Then you'll probably need to go back and redefine the base alignment.

[[To...]]

Typically, cylinders and circles always default to a positive space axis direction in Calypso, so it is a bit of a surprise to me to see -X on the cylinder. Was the model's original trihedron in a different orientation before you set up the base alignment? Then, did you modify the space axis options in the BA window? If so, it's probably a better idea to get the model in the desired orientation before extracting any features. Go to CAD > Modification > CAD Model Transformation. Use the Space Axis tool to rotate the model to the desired orientation. Don't worry about the translation/location of the triehedron, as the Base Alignment handles this very well but changing orientations in the BA means the original orientation information of the features prior to the BA will carry over and could cause a situation like you're seeing.


It could also be the way the cylinder was created in the model. If it looks right, then it's probably ok.

[[Ri...]]

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It's an order of operations error on my part.

This was the remedy provided to me which has stopped the random vectors after completing my base alignment:

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