Realized you asked about the 'time frame' -- I guess you mean # of bars to form?
Mostly, the shorter, the better. Because I don't want to watch it form all day/week/month/year long.
On a DAILY, it should form the CUP portion in about 2 weeks (10 trading days) to attract max attention. Usually the 'top' of the cup hits a new 52-week (or, at least) 20-day high before the 'end of day' folks see it. Then, they prep all their orders to buy the handle. If it takes more than 10-days, it probably won't make the cup pattern any time soon. Then, you get into 'big w's' and all that ilk...
As for saucers: I don't usually trade them. Too slow as a pattern. They are quite dynamic once they get moving but who knows when that will happen.
Take a look at AN for an interesting cup/handle. It's forming on the Monthly, weekly, and will likely form up on the daily, shortly. As for time frames -- it's a bit long for me but AN isn't a real 'day traded' stock. It's like a 'natural' c-cup vs. the stuff you see on steriods/implants on NASDAQ / QQQ.