"Connor Aston" wrote in message
...

I have made up a tabletop from planned 1 1/2" maple . The top is made
from 4 x boards each about 9" wide. I used Titbeond III to glue each edge
(there was plenty of glue) and spread out along the joint with a brush.
The problem is after it has been sanded (by a friend of mine on his pad
sander) at one end the joints have opened up by about a 1/16" running
down for about 4". I can't really see why this has happened?
My only guess is that the heat of the sanding has sucked a lot of
moisture from the Maple? And if the timber has shrunk by sanding it do you
think it will shrink anymore. I intend to cut the ends and use without a
breadboard for a more contemporary look.Has anyone else ever had this
happen. Each rough sawn board had at least
4" cut from each end before planning and glueing up.

I assume that you are saying that a glue joint failed, not that the wood
split.

I my best guess is that you didn't do a great job at the jointer. If you
had to use clamps to pull the joint together then that is the answer. My
suggestion is take time to dry fit everything before you glue. If the
joints need more that slight pressure to come together go back to the
jointer and fix the problem.