After two years my printer started making squeaking noises and wrecking prints.
It turned out the bed sometimes bowed and hit the Y motor shaft.

I'm replacing the Y-bar ends with the longer version to lift the bed.

In the process I thought I'd try out the flower nuts I bought from DX.

Search - Brass Flower Screw Nut - other places have them too.
Full title -
Jtron M3 Brass Flower Screw Nut / Die Cast Screw Nut / Mosaic Screw Nut.