Sword Forging!!! I love doing that here's a pic for proof (and not really to show off because i not good, the guy next to me is though! )
https://www.facebook.com/photo.php?fbid=10151095138552471&set=t.582780673&type=3&theater
and to answer the question the time varie depending if you want something shiny and also if you got either good arm endurance of power tools
In either cases to make a rough sword it'll take you about 3-5 day of constant hammering, if you got something as magical as a power hammer you can cut that to a tenth.
If you want something super good looking, fancy and usable, it'll take, by hand about 1 week if you're experienced and maybe two days with power tools.
Back in the days sword were not really made to last but most to equip a huge amount of manpower so even if you were good at fighting you would hope to have a decent sword that would not break on first impact.
For rust, it's not that complicated, you can mostly brush it away with sand paper or some kind of metal brush but if it's too rusty, don't even bother, you're metal is going to be porous and will become very fragile.
In secret of mana we're talking about a SUPER AWESOME MAGICAL BLADE OF AWSOMNESS, we don't really have that today...well thats not really true.
There's 2 kinds of blade that can withstand the test of time, 1 a katana made with really good tamahagane (it's a kind of metal, either look it up or read the manga "the sacred blacksmith" for more info)
and 2 the viking sword called Ulfberht, a sword that is considered on par with the katana for it's durability and incredible craftsmanship, vikings were the bawses.
Anyway hope this helps