Do you have to use acetone to clean in between layers of laminate, or is there something else I can use to clean after sanding?

Brilliant, thanks Warren!

I would've thought that if it has been sanded down with 120 grit ready for the next coat then there shouldn't be anything clean off the surface, i just washed mine in clean water once it was keyed with 120 and then when it was dry applied then next coats.