Peter, in Page Setup, you have the option of printing grids line even if under View you have unclicked the grid lines so you do not see them on screen.

Gridlines are of course separate from cell or group of cells borders.

I'll give that a go when I get home next week Sol.  I'm in UK at present.

 

I'm sure it's just something I haven't set up in the printing - all the grid lines etc. are there when I'm entering data etc. - they just disappear on the hard copy.