Why rockstar developers don't ask for help (2015)

Definitely a line between not asking for help and being productive.

There isn't really a specific length to hit, but once "cost of not asking" passes "cost of asking" is time to ask.

If someone else has experience in what you're struggling with, there is no real reason to not ask for help, as long as you put in a real effort and time to figuring it out yourself.