Binding Xrefs in Auto Cad

Binding Xrefs

On occasion, you will want to permanently attach an Xref to the host drawing. If you send your drawing files to a printing service to be plotted, including a set of Xref files can complicate things. Also, for archiving finished work, it’s better to reduce the number of files. There may also be occasions when the Xref has been revised for the last time and no longer needs to be a separate file. In all these situations, you will use the Bind command to convert an external reference into a block that will be stored permanently in the host drawing.

  1. Open the Xref Manager dialog box and highlight the Cabin12a Xref.

  2. Click the Bind button to open the Bind Xrefs dialog box.

    The two options in the Bind Type area have to do with how layers are treated when an Xref is bound to the host drawing. The default is Bind. It sets the Xref layers to be maintained as unique layers in the host drawing. With the Insert option, layers that have the same name in the two drawings will be combined into one layer. None of the layers in Cabin12a have the same name as any layers in Site12b. Let’s use the Insert option.

  3. Change the Bind Type to Insert and click OK. The Xref disappears from the list of Xrefs.

  4. Click OK. Your drawing looks unchanged.

  5. Click the cabin, and then type li¿. The text window shows that the cabin is now a block reference.

  6. Press F2 and click the Layer button on the Object Properties toolbar. The cabin’s layers have all become layers in the Site12b drawing and no longer have the Cabin12a| prefix.

  7. Click OK, and then choose Insert Ø Block. In the Insert dialog box, open the Name drop-down list. Cabin12a is listed here as a block, along with the window and two door blocks that you created in. One or two additional blocks may be on the list. These blocks are used by the dimensions in the drawing.

  8. Close the drop-down list by clicking a blank portion of the dialog box. Then click Cancel to return to your drawing. The cabin is now a permanent part of the Site12b drawing. If you need to make changes to the cabin part of the drawing, you can explode it and use the Modify commands to make those changes. Or, if you’re running AutoCAD, you can use the In-Place Xref and Block Edit tools that you used previously in modify the window block and, again in this chapter, to modify the roof lines and erase the front step.

  9. Save this drawing as Site12c.

This has been a quick tour of the basic operations that are used to set up and control external references. There are more features and commands for working with Xrefs than I’ve covered here, but you now know enough to start working with them.

Other Features of Xrefs

What follows are a few additional operations and features that you may find useful when you delve more deeply into external references. Play around a little and see what you can do.

  • Externally referenced drawings can have drawings externally referenced to them. These are called nested Xrefs. There is no practical limit to the number of levels of nested Xrefs that a drawing can have.

  • You can’t explode an Xref, but you can detach it from the host. The

Detach command is a button on the Xref Manager dialog box.

  • Large, complex drawings that are Xreferenced often have their insertion points coordinated in such a way that all Xrefs are attached at the 0,0 point of the host drawing. This helps keep drawings aligned properly. By default, any drawing that is Xreferenced into a host drawing uses 0,0 as its insertion point. But you can change the coordinates of the insertion point with the Base command. With the drawing you want to change current, type base¿ and enter the coordinates for the new insertion point.

  • You can limit which layers and, to some degree, which objects in a drawing are Xreferenced in the host drawing by using Indexing and Demand Loading.

  • A host drawing can be Xreferenced into the drawing that has been

Xreferenced into the host. This is called an overlay and is an option in the Attach Xref dialog box. Overlays ignore nested Xreferences.

  • If you freeze the layer that was current when an Xref was attached, the entire Xref is frozen. Turning off this same layer has no effect on the visibility of the Xref.

  • The Unload button in the External Reference dialog box lets you deactivate Xrefs without detaching them from the host file. They stay on the list of Xrefs and can be reloaded at any time with the Reload button. This can be useful when working with complex drawings that have many Xrefs.