Ofcourse I had to help so we can solve his problem. 

This tile system, let's you create, store and re-create your trench battlefield table effortless.

It only needs paint (and magnets) to use.

Painted result

Prototype designs

At this point it's a set of 6.  I also made some combinations so you get an overall idea.

Digital renders

Ofcourse some adaptors to connect the basic and wide trenche tiles.

digital renders

Made another tile with trench end/entrance

Added more beams and some damaged effect on the steel plates

Digital renders

Printed result (mostly prototypes