There was a whole tread here last year on the best way to grow corn in a raised bed.
it seemed no one could agree.
Also useful information on how deep to plant the seeds.
To deep and it play out.
Too shallow and it wont hold itself up.
Here is the same video I posted last year.
It has the machinery into play.
https://youtu.be/vgriLjxaVlgp
I have always planted 6 inches apart and one foot rows for hand picking in a small space.
Here is the video on how deep and why.
https://youtu.be/WvGKJ6GVuJQ