Checking or longitudinal cracks in ceiling beams

"tlc..." <[email protected]> wrote in message
news:[email protected]...
> We installed 8 6x12 white pine beams 15 ft. long in the living room of
> our new home built 1 year and six months ago. The beams are exposed
> about eight feet high with 6x6 white pine purlins 6 ft. long connecting
> them to the sloped ceiling. The beams were finished with Minwax stain
> and three coats of polyurethane. No finish was applied to the end
> grain.
>
> We have noticed checking or longitudinal cracks forming in some of the
> beams over the last year or so.
>
> Any ideas on how long this might continue or when the 'checking'
> process will stop?
>
> The house is humidity controlled to 45-50% RH year around.
>
> The beams are not an integral part of the house structure so strength
> is not a prime concern. I am interested in when the process will stop
> so I can stain the cracks and improve the appearance.

When the inner strains are fully relieved is the best answer. At that size,
it's dollars to donuts you've got a boxed heart. The radial splits will go
to the heart and stop. Structurally it's probably a push, the dryer wood
being more resistant to deformation than wet.

Stain when the opportunity arises, poly after you haven't stained for six
months.