I just took the rust off of a wok we bought at a garage sale with "Barkeeper's Friend", and it came off scary fast. Barkeeper's Friend is a cleanser whose active ingredient is a dilute oxalic acid, which you may also have around as a wood bleach.
However, after using it you should definitely rinse thoroughly and neutralize the areas you used it on with a mild baking soda solution, so unless you can disassemble the OF1400 to the point where you can rinse those posts, that might be overkill. On the other hand, a dilute solution and a barely moistened plastic scrubby (to avoid scratching those posts) very carefully applied followed by a wet paper towel with a bit of baking soda absorbed into it, might be just the thing.
No warranties, express or implied, etc...
