Make a mixture of water and baking soda and ensure that it is quite thick so that it can be evenly spread on the metal. You can also use a lemon in the same way. It is powerful enough to remove rust without causing any damage to the metal. It helps to use the left-over rind for scrubbing the resulting mixture. Make sure you squeeze as much juice as you can and then leave it for about 3-4 hours before you scrub it off. Sprinkle some salt over the area of the object that has rusted to ensure that it is completely covered. Lime and salt can also be very effective in removing rust.Try soaking the object in regular vinegar for 24 hours this will lessen the amount of scrubbing that would be necessary.
Using regular vinegar is also an option it would simply take more time to remove the rust. Another solution is using a piece of aluminum foil dipped in vinegar to wipe the rust off the object. Alternatively, you can also use a cloth soaked with it to wipe the object. If the object is too large, simply pour white vinegar evenly over the surface of the object and give it some time to settle. You can simply submerge the metal object in white vinegar for a couple of hours and then just wipe away the rust-like paste off.