cubfloater, when I have to join sheets together I take a streight edge and lay it on each sheet and cut it so that I get streight edges to work with and then pin them down tight together and then put a strip of masking tape over the joint. then unpin and fold them back opening up the joint so that you can put a bead of titebond in the joint. Then put them back together and wipe off the joint with a damp paper towel. Pin the sheets down and let dry. You should then have a good tight joint that will be easy to sand.