When making a craft check to create, for example, a Sunrod(DC25, 2gp), does that Craft check result x Craft DC allow for the creation of multiple items? If my craft check allows me to create 625sp for the week, do I create 31 sunrods, or just the one? Does that really mean that it takes me a week to make a single sunrod valued at 2gp?
If the check succeeds, multiply your check result by the DC. If the result × the DC equals the price of the item in sp, then you have completed the item. (If the result × the DC equals double or triple the price of the item in silver pieces, then you’ve completed the task in one-half or one-third of the time. Other multiples of the DC reduce the time in the same manner.) If the result × the DC doesn’t equal the price, then it represents the progress you’ve made this week. Record the result and make a new Craft check for the next week. Each week, you make more progress until your total reaches the price of the item in silver pieces.
If you fail a check by 4 or less, you make no progress this week.
If you fail by 5 or more, you ruin half the raw materials and have to pay half the original raw material cost again.
So the answer is no, but you can complete it faster so you can make more checks.
So for example if i complete a Sunrod in 30 mins, does that allow me to make another Craft check for that day to create another Sunrod?
The answer is yes. I forget where in the book the rule is, but there is a rule that states that even with exploring that adventurers could spend time crafting during days they go around adventuring. Therefore they have X hours. (2-4 if I remember correctly)
So long as your work is completed for the day, there is no reason you can't start up another product.