Why identical parts get different part position

In some cases it might happen that there are two identical parts that have different part position numbers. When you select the parts and select Compare > Parts from the pop-up menu, you might get the following message in the status bar: "Part geometry differs or parts are positioned differently in assembly."

Even if the part dimensions and other general properties were the same, there might be some other properties or settings that cause parts to get different position numbers:

• The parts have a different value for a user-defined attribute that affects numbering. In this case, when you compare the parts, you get the message "Part free attribute differs."

• The part orientation is different (vertical parts are considered as columns).

• The parts have different contour marking or pop marks. In this situation, two parts are not identical in real life, because they will be marked differently at the workshop.

• The parts have different number of vertices or handles:

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• The numbering settings use the Keep number if possible option for modified parts. This means that the previous position number stays, even if the part is modified to be identical to some other part. To fix this situation, use the setting Compare to old.

• The tolerance values are too large in Numbering settings. Try to make them smaller or use the default value 1.00 mm.

• If the Name option is selected in Numbering settings, the parts with different names will get different position number.
• If the part gets another position after welding to another part, the reason might be that the weld preparation is different, or that the part is inheriting the position from the assembly because the advanced option XS_USE_ASSEMBLY_NUMBER_FOR is set in the model.
• If someone has forced the part or assembly number to be the same using a minus sign in the start number field.