Not being able to overlay multiple wireframes is a limitation of the wireframe map type in Surfer. If you want to overlay multiple 3D wireframe maps, you can effectively do this by overlaying two (or more) 3D surface maps:
- Create the 3D surface maps.
- Select each surface.
- In the Properties window, click the Mesh tab.
- Check the Draw lines check box under Lines of Constant X and Lines of Constant Y.
- Click the General tab.
- Click on the Custom colormap (...) button in the Upper field.
- In the Colormap dialog, set to Opacity to 0% and click OK. The surfaces will look like wireframes.
Surface maps also have the added ability to set the limits of the map and to choose the frequency of the mesh lines, which is not supported by wireframe maps.
Updated October 22, 2018