Removing finish nails from molding is potentially difficult work, and is very fiddly. Most finish nails are very small, as they are designed to be hidden out of sight, and so before you can remove them from the molding, you will first have to find the little pests. Once you can find the finish nail, there are a number of things that you can do to ensure that they are removed from the molding without leaving too much damage on the face of your wood.
Remove from the Back
One way to get finishing nails out of a piece of molding is to take the nails out from the back of the piece. This will prevent the tools that you use from leaving marks around the head of the nail, which will cause damage to parts of the molding which are not covered over by the nail head. If you are reluctant to take the nail out of the back, as you are worried about the kind of damage that this may cause, then you should try pushing the nail upwards from the back of the molding until the nail is protruding, and then either use small pliers to grasp the head, or cut it off using a clipper, and withdraw the rest of the nail through the back of the molding.
Use a tool known as a nipper to take hold of the head and twist this part off, leaving the rest of the nail able to be taken from the back. If you find that you cannot access the nail from the back of the molding, for example if it is attached to other woods, then you may consider using a small pin punch to drive the nail completely through the molding from the front. A straight punch will go through without causing too much damage.
Use Small Tools
Rather than trying to remove the finish nails from the molding using your home improvement hand tools, such as pliers or a screwdriver tip, you should look for specialist removal tools, particularly ones which are small enough to move the nail out of the molding without damaging it too much. Using ordinary pliers can damage the molding, and may be unlikely to remove the nail. Look around for small pairs of nails, which will be available in specialist wood working shops. You could find pairs in toy making departments, for example, as the smallness of the items made require miniaturized tools.
Another key to removing the nail is to move slowly throughout the whole process. Be gentle, and prise off the nail, rather than trying to rip it out. Even if you are waiting to install another nail, or want to finish a job, you should remove the nail with patience, in order to avoid harming the molding. Wiggling the nail will damage the molding, so try and avoid this, and be sure to grip the head of the nail with something firm, such as a nipper tool.