separate LH tickets?
I need to have one institution buy me a round trip into and then out of FRA on LH. On the day of departure, I'd like to fly into FRA on a separate ticket bought separately, and then have an hour and 40 minute layover, and fly out on my return ticket home. So I'd buy two tickets:
Round trip ticket, with rough details:
Sept 1, USA -> FRA
Sept 10, 10:10 AM FRA -> USA
In the time in Europe I'll be travelling around in Europe. I'll use separate one way tickets to move around. A second ticket at the end would be:
Sept 10: 7am - 8:30Am, VCE - FRA
an I do this? Would I or can I, after purchasing both, "join" the tickets in some way, so that LH would take care of me if the first flight delayed? Or is this whole thing so unadvisable that it would be better to get back to FRA the day before flying home, even if just overnighting in airport hotel?
thanks in advance!
zczc