Whats the difference between pastry and all purpose flour?!
Answers: can you make up the difference with increacing the amount,if so how much to increase cup for cup
Pastry flour is lower in gluten. It is made from 'soft' wheats, whereas AP flour is made from a blend of wheats. You cannot substitute AP flour for pastry flour - it will make your cakes or cookies hard and crumbly. You cannot substitute pastry flour for AP flour either unless you add vital wheat gluten.
The main difference is that Pastry flour has far less gluten - the stuff that makes your dough stretchy and elastic.
So, depending on what you are making - you could just use all purpose flour with no problems.
You will need to mix it as little as possible to keep the dough as tender as possible.
Without knowing what you plan to use it for - I can't give any absolutes.