Some log building companies square the ends of the logs where they will be a square mortise inside the side of another log it's joining. (Some of these aren't always square, some are rectangular, depending on the load.)
I know this because they have asked the software company to make this option available from our tenon function, which it is if you use the correct function and set the parameters correctly.
All this joint work doesn't show as it is on the end of the log and inside the other, so from the outside it looks like round log.inserted into the side of a round log.
The below example is not for going into the side of a horizontal log but the side of a log post. I was just experimenting with the tenon function to create the squared or rectangular end as well as adding a standard tenon.
Last edited by Jim Rogers; 06/11/0912:22 PM. Reason: add jpg