Quote Originally Posted by Nr1madman View Post
This is how I did it.
First rail as straight as possible then I mounted the gantry and slid it back and forwards as I was drilling.
Then I took it off and tapped all holes.
Then remounted for tightening the screws and worked as close to the gantry as possible :)
I have a feeling that that is also suggested in the Hiwin manual. Certainly worked for me!