Using the Weld command

The Weld command is located in the right-click menu and is used to "glue" two separate objects together to make one.

To use Weld you must first make sure that the two faces have the same number of vertices or the weld won't work and Wings will generate an error.

i.e. these two will not weld because the cube on the left has four vertices, and the cube on the right has six.

Once you've established that the vertices will match up you can then put them together and use the weld command.

Hopefully, that was clear enough? Anyway, here's a video just in case.