Glueing ebony fingerboard end to spruce top
 

Today I glued an ebony fingerboard end onto the spruce top with
a spot of white classic titebond about 1 to 1.5 square inch size.
As ebony does not absorb like softer woods I´m not quite sure how long I should leave the clamp pressing it.
Would overnight do the job or is it better to leave it for about 24 hours...or even longer?

At least 24 hours.
 

Drying time for this type of wood glue is largely dependent on the water in the glue leaving the joint. Where the joint is larger the glue can take quite some time to cure; joining fingerboards to necks and bodies is one such example. I’d leave it at least 24 hours to ensure the glue has fully hardened.

I often glue lengths of veneer, perhaps two inches wide, using Titebond and the glue can still be wet towards the centre even after 72 hours. The clamping jig I use is lined with acrylic which presumably slows down the rate at which the water leaves the joint.

One hour is long enough. I usually leave them on for longer though. Some things like bridges and bridge plates I will leave on for at least 12 hours though.

Thanks for your replies!
I made a new nut and a new saddle as well and put the strings on.
The glued tip of the fb seems to be attached firmly.:guitar:
Sorry the real color is more to light yellow...;)
http://viento.zenfolio.com/img/s/v-10/p3792673984-4.jpg