Anet A8, Omni M505, Frame brace, Simple and sturdy.

Sturdy and simple frame brace.
Y-axis belt roll holder with room for a nut and washer ( print them with 100% fill).
Drill 8mm holes in the middle of front, aft and center frame 20mm from the underside (the middle hole can be 10mm to give some extra play).
put a 40 cm 8mm thread bar through and 8mm nuts on both sides on all frame parts.
this setup take up the force from the belt just on the right spot and do not transfere the tension force to any other part of the construction.
The roll hol