1200mmX900mmX170mm 4axis cnc

[Nr1madman]

How close can be the bearings on the gantry so I can have good accuracy and eliminate the tolerance when torgue applied on Z axis ?
The ends of the tubes is going to be welded with steel flanges, I prefer minimum welding for minimum stress and to be able to adjust- align everything.

Aah then I understand about the ends ;)

I don't know about the critical spacing of y axis bearings but I've seen lots of people using gantrys that are only 100mm high (50x100 steel tube) and that seems to work. The better question is what distans you are planning from lower y bearing to workpiece?

[Nickhofen]

Aah then I understand about the ends ;)

I don't know about the critical spacing of y axis bearings but I've seen lots of people using gantrys that are only 100mm high (50x100 steel tube) and that seems to work. The better question is what distans you are planning from lower y bearing to workpiece?

200mm maximum, with rising table that will minimize the distance for aluminum cutting .