Besides making sure belts are all tight and everything is spaced right (nuts/bolts);

My first print when testing anything is 20mm cube - Hollow or solid.
I do this whenever I build or tweak a printer, whenever I get a roll of ABS (to check quality) or any mods.

It's easy to see errors, size to see if anything is wrong, layers.
The hollow cube shows your bridging too! Gap to Gap.

Once it seems right, I print both together.