Good seeing. Fits the challenge nicely. You were successful in your limited depth of field attempt, but if it was mine, I'd probably crop about 1/3 off the top to keep the viewer in the picture longer.
No sense of a point fo focus in this, for me. The very shallow dof works against the image a little - I think just a touch more depth might have given the eye somehwere to dwell, for at least a while. The metallicness of the metalwork is fine, but I'd love to see some sense of the texture of the roller surfaces too. Not a bad use of mono though.
This could have been a good DOF entry. I personally don't like so much out of focus on a texture challenge shot because I think it's harder to really see the texture that way.