Sagulator question

[David Huston]

When using the sagulator should I select floating shelf if I am going to be using shelf pins?

[Kent A Bathurst]

When using the sagulator should I select floating shelf if I am going to be using shelf pins?

David - In one word: Yes.

In more words: Floating means not permanently fixed.

The point being - you get no structural support at the ends. As opposed to, say, rabbeted shelf, end-glued into dado sides.

With the pins, as the center deflects, the ends are free-floating, so the shelf can move more. With the fixed shelf, as the shelf tries to deflect in the center, it is also pulling on the sides - counteracts the bending/deflection.

You just need to compensate with stronger shelf material, or a thicker shelf, or a front lip [like 1-1/2" tall x 3/4" thick] glued to the shelf. Door #3 [using solid wood] is the most common, I would guess, for shelves made of ply or particle-type board.

Me - I generally make the shelves out of glued-up panels of the same hardwood as the case - pretty strong. And adjustable shelves annoy me. I came to the realization many years ago that the adjustable feature was functioning - for me - for a very short time span, until the case had acquired it's permanent occupants, and then the shelves never moved. So - I started using fixed shelves. Even in, say stickley bookcase repro's -Gus had pins + floating, but he ain't around to criticize me, so what the heck? That's just me, though - my own eccentricities. YMMV.