The name of the joint that makes two beams into one longer beam is a scarf joint. Yes there are more than one. And which one you use depends on where you'll be putting this longer beam. If you go to the timber framers guild home page and click on the section where you can down load a series of articles by Jack Sobon, you'll see section six 'scarf' joints, and you can down load the article and read up on the many listed there. Good luck, Jim
