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Next project is some bookshelves for my son's room. Worked this up on Sketchup (just learning, so forgive...):
The dimensions are:
39"w X 34.5"h.
Stiles and rails will be 3" wide and 3/4"ish thick ambrosia maple.
Shelves will be 3/4" mahogany veneered MDF. 37.5"w X 10"deep. They will be notched around the stiles and fastened to the top of the bottom and middle rails. It's not in the drawing, but I will add a strip of maple to cover the screws on the top of the shelf. I will also add a hardwood trim to the front and sides of each shelf.
Concern is whether the shelves will hold weight only being supported by the 3/4"ish thick rails.
Thoughts?
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you need to determine how much weight will be on the shelves. then put the numbers into the
Sagulator to determine the sag.
Books can be very heavy if they are hardcovers, paperback not as much.
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Quite simply, no. Way too much leverage on the shelves. The other thing to consider is making some way to conceal the fasteners into the studs and spacing the parts so they hit the stud centres.
Blackhat
Bad experiences come from poor decisions. So do good stories.
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Assuming that the stiles are supporting the shelf at the rear the sagulator is irrelevant as it does not address this problem. The shelves are to small for follio sized books and a little large for quatro (9½x11"). The follio size will run ~60lbs/liner foot. The leverage will be too much for the upper piece to support. The rails would be fine but the attachment to the rails from the top of the shelf would be too small. Also unless it is screwed to a wall stud it pull out easily. You could narrow the shelves to fit octavo (9x11) and probably get 3 shelves in the same space but there would still be too much torque on the supporting structure.
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I don't need sagulator to tell you that is too wide for MDF. The shelves will eventually sag even with nothing on them.
Is this a book shelf? If so, I would put sides on it and have a middle support.
If it is a display shelf, I would just add a middle support like the ones you already have.
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Turning the structure upside down, so that the bookends on top become shelf supports underneath, would do a lot help carry the weight. Then consider the previous good suggestions.
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Okay. Looks like it's back to the drawing board. Will keep Sketchup'ing and come back with version 2.0.
Thanks for the reality check.
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Your design isn't that bad, but the choice of MDF is. I see why you put the brackets on top of the shelf, to act as a book stop, and it should work fine as long as you mortise it into both the shelf and stile with the grain running vertically. If you made foxed tenons and under cut the mortises at the ends it would never come apart. I would move the rails up so the tops of them are above the shelf. That would eliminate the need to notch the shelf, make it easy to secure the shelf to the rail with screws through the back, and act as a stop to prevent books from hitting the wall. And it would look better, IMHO. If you switched to 1" hardwood shelves I think it would be fine.
John
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Use plywood or solid lumber instead of MDF.As another post mentioned it will sag with the weight of the books. Maybe you could do a half circle instead of the quarter circle under the shelves.This would give you the support needed and the book stop also.
Mortise and tenon for the rail to stile will be plenty strong.
I would not use biscuits for the connection,not sure if it is fail safe like M&T.
mike
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Okay. Version 2.0:
Added some supports under the shelves. Don't have the joinery worked out just yet (never done M&T...), still trying to work out a design that will hold my son's pile of kid's books.
The dimensions will likely change a bit as I will adjust for stud placement such that I can drill in through the front of the rails into the studs. I'll plug the holes (thanks, Dave).
Just realizing I forgot to add the trim around the shelves. 3/4 x 3/4 mahogany all the way around each shelf.
Am I getting closer?
Found some wood effects to use. Loving me some Sketchup!
