All else being the same design as an SD3 there really shouldn't be a structural issue. That doesn't mean it's the best design but it is adequate. You should check the bushings to ensure they are properly installed and everything else is secure. Then add a small amount of grease to those guide rods and the threads.
As the table is moved a soft grinding sound can be heard from the assembly which is remedied by applying slight upward pressure on the table.
I can only assume that the moment (torque) being applied to the leadscrew and z rails from the massive cantilever beam that is the table will cause issues in the future when it comes to z dimensional accuracy and wear on the leadscrew. I am diasappointed that another rail at the front or counterweight was not included in the design to counter this problem. It isn't an issue on the sd2 because the 6" bed is much shorter and lighter by far, but I can see the droop in the table on this machine.
I would like to hear from a designer or engineer regarding whether this is actually an issue or if I am overreacting.
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