I can't reach focus!!!

Dear all,

I have small problem. After I bough Flip-Mirror system I can't reach focus
in my camera/eyepiece :S . I have a Newton refractor.
When I'm testing system with simple eyepieces the focus
can be reached when eyepiece-output moving to secondary mirror and
almost all lie down in telescope tube. What I should to do buy any
reducter or barlow? Maybe a 1.6x Barlow can
be suitable? I know that it changing focal ratio. And what
about OCA/OCS systems? I hope that I correct name
such systems. I just saw them first time in Internet-shop...