You can earn up to 50k in 24 hours before you hit the gold curve normally, or up to 160k if you have used an extra gold potion or have donator status (you get donator status for a month by purchasing an item over 249GC). The day starts at midnight PST, so if you don't live in that time zone, it will be a slightly different time (eg. for me, the gold cap resets at 7pm).
I think that's about 10 rounds of Papa Saw normal to hit 50k (I don't play much saw mill, so I'm not 100% on that figure).