Ahh thanks for the description. I was thinking in the wrong plane...now it makes sense!

I'll put the rails right on the edge of the plate since that gains about 10mm.

rather than spend the rest of you life trying to calculate them just make the machine as ridgid as can and then cross your fingers
Yes, I'll make it as it is now. I'm currently waiting on my Mum/Dad to give me permission to buy the bearings. Then I hope to find somewhere better to buy the aluminium plate!

I'm intending to have this router finished before I start University, so 21-09-10.