Timber Framers Guild Forums Tools Timber Engineering Purlin/ridge and posts

Hi,

I am trying to so a post and ridge roof system with round and square log/timber. However, I am having trouble with designing the mortise and tenon. Any ideas with the depth needed etc? Also, how will I cut them?

Thanks

Since the rafter tenon should not be cut cross grain, then the mortise will be inclined, to maximise strength of the beam the center of the tenons length should at the height of the neutral axis of the beam.