ORIGINAL: bigbulls

Lumenoks crack the ends of your arrows as you have noticed and they do not work on anondized aluminum. You can gently file off the end of the anondization (is that a word?) on the end of the bulldog collar to bare aluminum, like a unibushing for an aluminum shaft, and they will work fine.

Or you could just scrap the lumenoks all together and use one of the many other lighted nocks that are far superior to the lumenok.