French Cleat for Library Shelves

[Angela Ryser]

I am building some box shelves to float on the walls of my library. I will be cutting the top and bottom of the shelves from 3/4" birch plywood and using a 3" piece of poplar to make the front portion. One of the shelves will run all the way around the room just above doors and windows. Other shelves will vary in length. I want none of the hardware to show and I don't want to use any end supports. Can I use French cleats or will they not bear the weight of the books?

Thanks for any and all responses as I am a novice!

[Eric DeSilva]

I would say that inherently, a french cleat has rather good holding strength. The real question may be what/how you attach the wall cleat to the wall (bolt to the studs being best bet) and how the cabinet cleat attaches to the cabinet (glued/screwed into side/tops? biscuits? tenons?).

[Angela Ryser]

Hi, Eric!

Yes, I will be attaching the cleat to the wall at each stud. Is there a difference between a "bolt" and a "screw"? Larger diameters? I was planning to screw the shelf portion of the cleat to the underside/inside of the box. There is actually no cabinet at all, just the box (top, front, bottom with backside open to the wall) shelves.

[Jim Becker]

French cleats can give you some wonderful power to hold up cabinets and shelving in a concealed way. For shelves that are going to hold books, "I" would likely try to do it with a double one, however...top and bottom. And yes, those cleats should be fastened to studs. For this application I'd seriously consider using lag bolts, (predrilling for them) rather than just #10 or #12 screws, although the latter can provide some good holding power if they are quality fasteners.

[Todd Burch]

I use French (Chinese, whatever) cleats for all my shop cabinets. I use 5/16" lag bolts, 2 into each and every possible stud. They hold some SERIOUS weight.

As such, I countersink a hole for the hex head and use a flat washer as well. Countersinking a piece of 3/4" material for a lag bolt head and flat washer requires roughly 40% of the thickness of 3/4" material.

On a recent shop remodel, I noticed that one of my cleats, made of out 3/4" ply, was starting to split between the inner veneers. It wasn't so bad that I ran and made a new one, but I won't be using plywood for cleats any more. 3/4" pine is plenty strong.

Todd

[Gary Keedwell]

I made some shelves for all my magazines ( man they are heavy) and they are hung on french cleats using ordinary wood screws. Been there a long time and it will even hold my whole body, too. ( I tried);) Just make sure you screw into studs.

Gary

[Fred Voorhees]

Todd and Jim - - - you two may have just inadvertantly taught me something today. You used the terms lag "bolt" where I would have used lag "screw". I googled the term lag bolt and it seems that the terms are useable either way for the same item. I have always thought, and maybe correctly so, that there are definite lag screws and definite lag bolts, with no crossover between the two. Sheez, you never stop learning.

And, definitely, I would go with this method also. Strength guaranteed!

[Jim Becker]

Fred...good point. I think "technically" they might be better called a "lag screw", but I've always heard them called "lag bolts". I guess the stud you're putting them in is the "honorary nut". Of course, that may also be "us"... :D

[glenn bradley]

This may also apply as you are talking about an assembly that is deeper than it is tall:

http://www.woodnet.net/tips/general-shop-tips/hanging-cleat-modification/

[Angela Ryser]

Good Morning, Gentlemen!

Thanks for all of the input. I don't feel nearly as leery of this application as before!

Have a wonderful Thanksgiving!

A