I shoot Carbons, one arrow developed a small, 1/2" crack near the arrow knock. The knock can come out if you pull on it. Is the arrow any good yet, can I puta little glue on the end ofthe knock to seal it?

I would get rid of it!!! No need to injure yourself over one arrow.

Pitch it.....it's not worth it.

Damaged carbon? Throw it out!
Warning: The attached picture is graphic! But it demonstrates why it isn't worth it!

Don't shoot it. Not worth your health.

I'll pitch it. Thanks guys.