Title Block Attributes Reset After a WBLOCK Round Trip
A firm's title block is a block named TITLE-A1 containing attributes for SHEET_NO, SHEET_TITLE, and REV. The block also contains a nested block for the company logo. A drafter needs to send one sheet's title block to a consultant as a standalone file. He uses WBLOCK, selects the title block insertion, and saves it as TITLE_SEND.dwg. The consultant inserts TITLE_SEND into her sheet and reports that SHEET_NO and SHEET_TITLE show their tag names rather than values, and that the logo is missing. The original drawing still displays correct values. The drafter also notices that when he later edits TITLE-A1's attribute definitions in the source file, existing inserted title blocks on other sheets do not pick up a newly added attribute.
1. Explain why the exported file lost the attribute values and the logo, and how the export should have been done.
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WBLOCK writes the selected objects as they exist, but attribute values are instance data attached to each insertion. When the title block insertion is written out, the attribute definitions travel with the block definition, while the per-instance values may not be retained in the way the consultant expects, so the tags display instead of values. The missing logo indicates the nested block was not included: WBLOCK does not automatically bring in nested block definitions unless they are part of the selected object's definition or the option to retain them is used.
A safer method is to use the block definition itself: insert TITLE-A1 into a new drawing via DesignCenter or the INSERT dialog, or use WBLOCK with the block option so the full definition including nested blocks is written. After insertion, the drafter should verify attribute values and use BATTMAN or the Properties palette to confirm the attributes exist and are set to the intended values before sending.
2. Explain why new attribute definitions do not appear in existing insertions and describe the correct update workflow.
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Adding an attribute definition to a block definition does not retroactively add that attribute to blocks already inserted in the drawing. Existing insertions were created from the old definition and keep their original attribute set. The new definition only affects future insertions.
The correct workflow is to run ATTSYNC after redefining the block. ATTSYNC updates existing insertions to match the current block definition, adding the new attribute (with its default or blank value) and removing attributes no longer defined. The drafter should first confirm the block was redefined properly (for example with BLOCK, selecting the existing name and choosing to redefine), then run ATTSYNC and select the affected blocks. He should then fill in the new attribute values on each sheet. If many sheets are involved, a script or batch tool that runs ATTSYNC across drawings is preferable to editing each one by hand.