I was trying to get an idea of the size of Extrusion one would use if designing a L gantry for a 6040 sized machine.Sorry if I was vague. I was referning to the '40' sized extrusion.
My present incarnation is using 80 x 160 extrusion for the Gantry ( no L section.)
If I was going to use the L configuration, would I still need to use '80' extrusion or could I get a good result buy just using '40' extrusion in L configuration?

Its a early question that affects the rest of teh design and important to get right.
thanks for your help.