How do I combine the 50x50 studs base plates to get a stable build plate to build my Mosaic design upon?

With every Art4Bricks order we ship a bunch of 3D-printed transparent connectors, designed specifically to interlock any number of 50x50 base

Blender visualization of transparent 3D-printed connectors, designed by xplicator specifically to interlock any number of 50x50 base plates with each other

plates.

Use these transparent connectors to combine the 50x50 plates on the back side with each other.

Additionally, you can use those connectors as hangers to put your Brick Mosaic Art Masterpiece on the wall. 

 

Backside of 4 50x50 studs base plates interlocked with transparent 3D-printed connectors designed by xplicator specifially for this purpose.
Since the Art4Bricks Mosaics consist not only of 1x1 plates, but also of 2x1 and 2x4 plates, to build the mosaic design, these naturally span and combine the 50x0 base plates providing additional stability and reenforcing the overall structure.