Volvo G990 Grader

[JensR]

Agreed, although we should not forget that the skill to design something like that in CAD in a cost-effective and functional way is also considerable.
Ideally, you'd still need have some machined/turned parts, like Stefan's axle carriers.

For smaller scales/models, I think you might find that glueing degreased metal offers more than enough strength, especially if you take it into account during design.