How to Create Fabrication CADmep Sub-Assemblies

February 14, 2022 Heather Volk


Creating a Sub-Assembly combines multiple items into one which will make modeling faster. Sub-Assemblies can be saved as a catalogued item, customized product list or as a Sub-Assembly.


To create a TOL, nipple and dielectric union sub-assembly:

  1. Select service to get parts. Add the Thread O Let (TOL) to a piece of pipe. In this example I will be using the 2 x 6 TOL.
  2. Add the threaded nipple.
  3. Then add the Dielectric union.

  1. Type in the command “Savesubassembly” and select objects. Select the TOL, threaded Nipple and Dielectric Union and select enter.
  2. Expand the “Imperial Content” folder and create a “SubAssembly” folder to put items in.

  1. Save Item File As a part:

You will want to add the size of the TOL for reference.

Then select Save.

  1. Next, create an icon/ image for the new SubAssembly.

Go to the folder button on the Fabrication Toolbar.

Click the plus sign next to “Imperial Content” and path to the “SubAssembly” folder.

Next create an image for the item, otherwise it will not look like a part.

  1. Right click the item missing the image and select “Edit”. Click the “3D View”, the isometric button, then take a screen snip of the image. (Snipping Tool is a free screen snip tool that comes with Microsoft).

  1. Create “New” snip:

  1. Go to File and select “Save As” and go to the following path:

C:\Users\Public\Documents\Autodesk\Fabrication 20xx\Imperial Content\V3.06\Items\Imperial Content\Mechanical\SubAssembly (folder path where subassembly is located)

  1. Name the image the same name as the SubAssembly created. Save the file as a PNG.

Adding to a Service:

The next step after SubAssembly creation is to add the item to a service.

  1. Set the service you want to add the .itm to.

  1. Click the “Edit Service Database” button to the right of the service.

  1. Click “Service Information” to add the new .itm.

  1. Click the plus sign next to Imperial Content and path to the SubAssembly folder.

  1. Before adding the item, set the condition first.


  1. Click on the 2_TOL_DU and drag it to the items built into the service on the right. As you are dragging the item over, a plus sign will appear. Do not release the item while hovering over another item as it will be added to that part.