Sagging Shelves

[Steve Roxberg]

I have some shelves that are 31" wide, 3/4" melamine over particle board. They are sagging due to the weight of my magazine collection (yes woodworking).

The sides of the shelves and the shelves are the same width today, and I'll probably like to keep it that way.

How would you recommend beefing them up a bit?

I was thinking about putting a 3/4 " thick piece 1" tall and adding it to one edge and then ripping 3/4 " off the other edge.

Would that do it, or is there an easier way?

[Dennis Peacock]

I'm thinking....with that much weight? You need center supports all the way to the bottom of the shelved unit to transfer the weight from the sagging shelves to the floor. This will straghten them up and provide support to stop further sagging. Just my 2¢ on this.

[Steve Cox]

Depending on how important appearance is to you I would just use pocket screws to attach a board (1 1/2" high?) to the bottom of the shelves. You could set that back from the edge a couple of inches to make it less noticeable.

[Steve Roxberg]

Appearance isn't real important they are in the shop.

That would be quick and easy, thanks.

Any other ideas?

[Jim Becker]

A piece of angle iron at the back and on the bottom of each shelf will help and be further enhanced by a 1"-1.5" wide facing at the front of the shelf.

[Wes Bischel]

Steve,

What Dennis said. Plus I'll add I've used steel angle along the back edge of the shelf in the past. (and under the front of the TV shelf - it's 300lbs)
Also, check this out:

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

It worked pretty well to calculate what would hold how much.

Wes

[Steve Rowe]

Steve,

Assuming you can disassemble the shelve and have enough height between the shelfs, I would cut a dado 3/4" wide and 1/4" deep near the front edge of each shelf. Then I would glue a piece of hardwood approximately 1" wide in the dado the full length of the shelf. This should provide additional support to prevent sagging.
Steve

[Bart Leetch]

I don't know if this applies to your shelves. These aren't fancy but pure function. I was looking for a way to get some things off the floor to gain floor space in my small shop. Where these shelves are were some sagging shelves 12" - 16" deep These shelves are 24" deep & I can hang my 190 lbs anywhere along the edge with no effect at all even with the items that are already on the shelves.
The triangle plywood shelf bracket is notched at the top back upper corner for the 2x2 that is fastened to the bottom of the plywood shelf to fall into. The back edge of the front edge stiffener for the shelf is rabbeted & glued & nailed.

In a new bigger shop with a 10' ceiling I'd start out with a shelf like this down from the ceiling about 12" maybe lower in some places all around the shop with a french cleat around the the whole shop below that where I could hang cabinets.

I hope this will help someone.

[Vaughn McMillan]

I handled a similar problem in a particle board/melamine utility cabinet from the Borg with 1/8" thick x 1" extruded aluminum angle on the front and back edges of the shelves. When I beefed up these shelves, they were sagging about 1" in the middle. Since I was storing canned goods in the cabinet at the time, I also wanted a lip on the shelves, so the aluminum angle protrudes above the edge of the shelf about 1/4". I used machine screws, washers and nuts to pull the shelves straight. As the pictures show below, looks were low on the list.

Here's a shot from below the shelf. I never did get around to trimming the extra screw length; they just haven't been in the way.



And here's a detail shot from above showing one of the countersunk flathead machine screws:



When shelves started sagging, the sides of the cheapie cabinet started to bulge outward due to the weight on the shelves, so I pulled them back together with a piece of all-thread:



Nothin' fancy, but they've held up well.

My garage has a bunch of similar Borg cabinets permanently installed along two of the walls...something from the previous owner. He was into high-powered target rifles, so he beefed up the shelves to store ammo. He used 2x2 fir on the underneath side of all four edges of each shelf, and permanently attached the shelves to the sides and backs of the cabinets. I'll spare you the pics, but it's great for tool storage.

- Vaughn

[Ken Garlock]

A piece of angle iron at the back and on the bottom of each shelf will help and be further enhanced by a 1"-1.5" wide facing at the front of the shelf.

I second that, Jim.

When I put up some utility shelves in the back garage for my wife to use, I put 1/8x1x1 steel angle along the front edge of the 3/4 plywood. Painted the angle iron with Rustoleum, and drilled some holes for screws on the bottom side of the plywood.

I don't expect those shelves to bow any time soon.

[Steve Roxberg]

Well I went with Steve Rowe's suggestion and cut a 5/8" (I had some scrap Oak) groove near the front, and then screwed in some 1 1/4 inch tall oak strips.

Works great, but his directions stated near the front edge, so I went 1 inch back.

Would anyone care to guess where the shelf support brackets sit in relation to the front of the shelf?

AHHHHHHHHHHHH