How to change Timemachine 2TB to the 3TB

[Microman]

I have a 2 TB drive that I was using for a few different family members for doing Time Machine backups.

I would like to copy my DATA, and use the 3 TB to use if for MY Mac book and possibly others,

I tried it once before, but Timemachine would always say that it was doing backup for the first time, even though the data from previous backup was on the NEW drive. ANd I chose the new drive as the timemachine backup.

Is there some sure fire way of getting this done.... A How to, that someone uses.

Thanks.

Right now , I am cleaning up my Macbook, so that I can do a backup, getting rid of some files, before it has to do all the backup.

[Chakravartin]

Apple has a kbase article on it, but I've found that their method gets iffy results.

SuperDuper clones TM vol's very nicely.