Hi,
I’ve created a solution for handrail posts involving sinking an entire 2 x 2″ post into a mortise, set into a much larger timber below. No tenon, no shoulder. The whole body of the upright.
I cannot find any information about such a thing. Is there precedent for this? Does it have a name?
Edit: Many thanks for all the replies. Just to clarify; I did not think I was inventing something new and doubtlessly worded my query poorly. I can see all the ‘cons’ involved in this solution now, and will revise the design.
many thanks again.
Replies
I'm sure it's been done. Everything's been done.
You still have a mortise and tenon though. The part of the post that goes into the hole is a tenon, even though it has no shoulders. A tenon missing a shoulder is usually called a barefaced tenon, but there are a bunch of names.
The shoulders do add something to a joint, helping with racking forces.
Agree with John C2; the shoulders make a M&T joint much stronger against racking forces. Without them, the sides of the tenon are easily compressed, loosening the joint. With them, their end grain (which is much less compressible) prevents the joint from angling and compressing the side of the tenon.
There are many reasons that there is a shoulder on the posts.
Maintaining depth or distance between base or sill plate and rail. Aesthetics. creating a shoulder or skirt around the mortise not only looks better but keeps dust/debris and in outdoor situations, keeps water out of the joint. The shoulder also adds strength by helping to resist racking of the joint.
Believe me, your "solution" has been considered before, it just has too many drawback to utilize.
Compression from expansion will make the post loose in the joint. If this is in weather it will be more --except in wet weather when it will expand and be tight. . Eventually crud will find its way into the joint, if outside earwigs and soccerball bugs will make it a home. Otherwise ,the joint will work just fine assuming that the top and bottom rails are fixed and not dependent on the tenon for stability.
"Compression from expansion will make the post loose in the joint"
I don't know what you're saying, could you please explain, thanks
Wood expands from moisture/ humidity. It's trapped in the mortise or the axe head - the expansion compresses the wood fibers and when the wood goes through a dry cycle ,like when the weather the changes = loose joint or scary loose axe head.
That made a lot more sense than what you wrote the first time
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