Why was Joseph not at the Crucifixtion?

No one knows what happened to Joseph as the last we hear of him is when Jesus was at the temple at age 12. As the average age of death back then was around 30 years old, it's assumed he probably had died years before. Maybe he was there, but it simply was not recorded.

It's assumed that he had died.

Tradition says he was dead.

Joseph had died before the Crucifixion of Jesus the Christ of Nazareth, the Messiah. <t><

He was dead. So, maybe he was there in spirit.

He was probably dead by then.

yep, he should have protected his son?

It's quite possible that Joseph had died during or before the time of Jesus' ministry.

Legend says that Joseph was killed when Jesus was 23 years old when he fell off a scaffold and broke his neck

He had a birthday party to attend.