repaired a damaged HDD successfully

previously i have opened 2 hard disks one was laptops and the other one was desktops, but at that time i was not successful but to day with a lot of patience and concentration i was able to repair a damaged segate 500GB hard disk and now using it well... it was actually the external hard disk which was of maxtor a but the hdd inside was segate's... quite funny but true....

with this what i have learnt that we require just a room with no dust present practically a vaccum room to protect the inner disks from dust which a crucial one and utmost concentration during disassembly