It's really risky process to recover disk partitions on a damaged hard drive. There are a lot of opportunities to lose your data, even if you apply the greatest data recovery tools and really sure in all your deeds. You should realize that all the changes that are done to a corrupted disk are irreversible. You may easily overwrite vital information about your HDD, files and data. First of all the backup should be provided before the start of disk recovery procedure.
But there are also some other ways of data recovery that are more harmless and easier in utilization, that don't need to have backup and repair data. You may not make a substitute copy of the drive, but you can do a total double image of it or its partition. Then you may persist repairing with diverse settings for so many times as you wish. This is 1 of the ways that is utilized in ntfs recovery programs.