Alternatively, if you don't want to use wood bracing under the plywood, you might increase the number of supports so that the unsupported span is shorter. Edit: as the original poster and Henry Jackson suggested, the Sagulator cannot help directly with optimizing the position of the supports for the shelf - it only calculates the sag of a given length of shelf, and cannot provide the sag for a shelf that is only supported at one end. I've got 122x25x1cm and 61x25x1cm plywood boards that I want to use to make shelves for books and tools. e. only the mechanical formula is used (based only on the dimensions and the properties of the wood). Enter The Sagulator - it's a free online calculator for sag of shelves which is a wonderful tool exactly for these questions.

L Bracket (up type) - Various Colours | The Metal Bracket Co

You might consider using three support brackets for the longer shelf so that each unsupported span is 61 CM. Running your 2 shelf sizes, the larger shelf span (122 CM) won't hold more than about 2 KG overall without noticeably sagging. With thick enough shelving, you could go for every other stud, but 10mm plywood is pretty flexy-bendy stuff when it comes to long term loads. Comparing the two formulas ("Critical Deflection" in the first vs "Deflection at the unsupported end" in the second), one notices that the calculation is the same (Wl