Here is my first mortise and tenon. I made this with my “dedicated mortiser” ($10 DP with delta mortiser attachment permanantly installed). The joint is tight! I trued up the tenon with a small plane to get a snug fit that required a rubber mallet to join together. Yes, I am Norm fan. There is a small crack at the top. I credit this to using scrap wood that wasn’t squared up.
ABOUT THE DEDICATED MORTISER – Yes. I realize the fence is on backwards. My old benchtop DP is shallow in terms of chuck to standpost. I would not be able to center the bit on even a 3/4” edge if the fence were facing the correct direction.
Also, I’ve heard people say using the Delta mortise attachment on a DP is bad news due to small weak handles to drive the DP. Granted, I was only working with pine, but I was able to use all bit sizes even up through 1/2 inch without much strain on the handles. I secured my work piece to the fence, started the bit into the wood and then drove the bit with both hands on two different handles. This might sound dangerous, but with the fence and clamps I felt quit comfortable.