Prints come out almost perfectly (no bending of the heatbed from roomtemp to 125deg C.
Just printing some slideons for the cable at the end of the rail.
Thx to everyone for their advice and help on this topic!
@Mark_Rehorst well kind of. Its a thick milled aluminiumbed yes. With glas on top 
@David_Sherwood its allways flat with glas, kindof. But when it bends it tilts and rises