Hey dean great thank you very much for the information on the Rails I have been looking and will be most likely going for those OEM rails, It will be purely a home Cnc just for hobby work so sounds good enough for me.

I will add some more bracing to the design higher up too.

The original plan was to make foam moulds for fibreglass parts for a car I was building so I could then keep layering up the foam and moving the shelf down to create the arches and other large parts, But that has changed now :(maybe one day) but its going to have a movable shelf for sheet woodwork so once the shelf is in that should also add to the strength too.

I originally left the ends open for end-grain cutting but I will add the end bracing too and I can always take them off when I'm doing normal sheet work.

thank you