1 inch t-slot extrusion scale up of kossel mini

I plan on building several 3d printers, so using locally obtainable large/heavy pieces is a must. Locally all I can find are 1 inch (and larger) T-slot aluminium extrusions. I measured and scaled up by 1.666666667 in replicatorG and printed a small test (partial) piece that seems to fit my extrusions. So I am now printing a full top corner piece (5 stinking hrs)

I have 3x600mm and 9x240mm (dude made me convert to inches before he would sell it to me....)

in 1 inch, 240mm looks strange