The issue of when to begin iron palm training can sometimes be a debated subject. At some kung fu schools, a student must train for 3 years before he will be introduced to iron palm. Other schools believe that iron palm training should be started as soon as the student grasps the basics (stances and such).
Each school of thought has its advantages:
Waiting 3 years to begin iron palm training - The reasoning behind this theory is that because iron palm is a special skill that shouldn’t be taught to just anyone, a student who has spent 3 years of his life training in his kung fu art has shown that he is dedicated. This dedication can be one aspect that the sifu looks at to see if the student is worthy. Additionally, after 3 years of training, the student will have mastered the basics and will be able to easily begin and incorporate iron palm drills into his kung fu training.
Beginning iron palm earlier in training - The main idea behind this idea is that the student will be able to defend himself better once he has spent some time training iron palm. Of course, no kung fu school would begin iron palm training on day 1, but under this idea it can reasonably be expected to start after the student has learned the basics (such as the various stances, strikes, etc.). Additionally, in some kung fu styles, iron palm may be integral to the system and waiting to begin that portion of the training would cause a gap in the student’s knowledge of his art.
Essentially, there needs to be an agreement between the student and the teacher as to when is the correct time to learn. It’s just another aspect that must be taken into consideration both when a student is choosing a school and when a sifu is choosing a student.