http://www.woodbin.com/calcs/sagulator.htm


"Vlad" wrote in message
ble.rogers.com...
: Hi all,
:
: I am planning a couple of bookshelves to be made from a 1/2 inch plywood,
: 35x11 inches in size; some shelves will be fixed in 1/4 inch deep dadoes in
: the sides of the bookcase and others will be "floating", supported by pins
: inserted in 1/2 inch deep holes. The shelves will only be supported on the
: sides; not along the length. Should I worry about the sag of the plywood?
: What's a good length of the shelf that can sustain a load full of books
: without additional lengthwise support?
: Thanks!
: Vlad
:
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