I am making this credenza (https://imgur.com/a/MjEC3) for a friend. It is 8' long and they plan on putting a 50" TV and some decorations on it. (Ignore the doors on the model. They are going to be a sliding barn door style I just dropped them in for size reference)
The idea I am working through is a long open space in the middle. (i.e. no vertical dividers) The top rail in the front and back is poplar at .75" thick and 3.5" wide (or tall as pictured here). I have a 1.25" deep tenon going into the supporting legs on each side.
There is also going to be a back on it. Probably 1/2" plywood or something.
Is that going to be enough support for the kind of weight mentioned above? I could add vertical supports connecting the top/bottom rails but I would rather not.
to be clear, I am just worried about sagging on the top. The top piece of wood is 1" thick solid oak. My guess is it will distribute the weight across the whole top (legs, side assemblies, and the long rails) but I have never built anything at this scale.
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