Adding table-like hor/vert lines

Hello,

I print a large table dierctly without @Table via
/ and |  positioning.

That works fine.

What I now want to do, is: adding table-like lines (hor/vert) at
specific lines / columns, without switching to @Table.

Is there a (hopefully easy) way to do this?
If so: how to do it?

Ciao,
  Oliver