Well the photos really tell the whole story really . I'm gutted, I haven't even had a chance to use these yet as they've been sitting in storage waiting for the other parts of my machine to be cut.

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The room they were stored in wasn't heated and I'm guessing there was some condensation. The one long screw (x-axis) has been hit badly and the z-axis isn't great. The other two have got off much more lightly though with only a few small spots of rust.

The big question then is do you think they are salvageable? If yes what is the best way to go about cleaning them up? I was thinking wire brush followed by a dowel wrapped in wet and dry with WD-40 as a lubricant.