post repair

My barn is around 100 yrs old i was told ,has a shed built on post and beam. some of the posts are cracking in the middle, is there a good way to fill some of the cracks and other voids, post are 6x6

Joe, the cracks are the standard effects of wood drying over time. They will not, usually, weaken the timber.
Why do you want to fill them in?

Jim Rogers

its a cross beam on two post. when should I worry,