tailblock thoughts, talk me out of this
 

So, tailblocks. Traditionally something between a 1/2 and an inch wide. Traditionally widely (fully) attached to the soundboard. Why? Picturing the soundboard and it's movement in my mind, it seems like having the entire width of the block attached to the top makes for strange shapes and low modulus of elasticity in that area. What if I chamfered the tailblock on top so it attached by the same width as the kerfing? It SOUNDS like a better plan in my mind, but maybe I am missing something...Would it negatively effect the structural integrity? I'm not picturing it. Talk me out of chamfering the top of my tailblock to match the width of the kerfing.

That is how I do it and have seen other do it also. And then others don't, personal preference.

It's a pretty common thing to do. I do it this way myself as too many times I can see the 'print' of the tail block on the top itself on older guitars.

I chamfer it.

Although it does make some sense to have extra glue area there at the center, since in high humidity, the soundboard and back try to expand, and stress is concentrated there. But standard linings are wide enough that it shouldn't be a problem except maybe with an ebony back, due to its crazy high expansion rate.

I make a plywood tail block out of spruce top scraps that is about 1/2" thick.

I've never had any issues with ebony backs, or any other wood, related to tail blocks.

Appreciate it guys, I'll chamfer it on top but not for the back, I think

Here's the tail bock on my Klepper, much like what you suggested. So, it seems no one is willing to talk you out of it. :)

It may affect sound, but I think a better reason is that it helps avoid the wrinkle/pucker that you sometimes see at the tail block.

https://vtoddyates.files.wordpress.c...pscqt7lw4q.jpg

I chamfer top edge but not back.