Y Axis linear rail positioning help advice

[Voyager]

starting to put my base together from 50x100 Misumi milled face profile, Y axis is 1100mm,
can anyone give me feed back on the pro's and cons of either mounting the rails on top of the profile or mounting on the sides (cheeks)
on top makes alignment between rails a little easier but not that side mount is impossible.
on top will raise my gantry by a bit,

what is the preferred method ?

Dave

[JAZZCNC]

On top would be my choice, it's much easier and allows a stronger gantry.! . . . . However, must say these sort of decisions should have been made a long time before you started building the base. If you are taking the design as you build it route then expect a lot of wasted material and design changes.

You'll save your self a lot of grief and money if you sit down and design all the major areas of the machine first.

[Voyager]

However, must say these sort of decisions should have been made a long time before you started building the base. If you are taking the design as you build it route then expect a lot of wasted material and design changes.

have most of the design pretty much fixed, however what looks good in CAD does not always translate to the real world, Many things will change as the build takes shape, as i discover the disconnect between Screen and reality.
Y rail position is a fairly easy change at this point.
I have worked on cheek mounted rails as thats how things evolved in CAD but as i start to construct that little devil on my shoulder keeps questioning my decisions.