Shelf max width from 1/2 stock

[jfynyson]

I'm designing a small spice rack to go next to our stove. It'll be made from sapele that I'm planning to mill to a ~1/2 thickness. The shelves will span a 22-1/2" area, will be 3" wide and the spices are mostly very light weight in plastic jars. I'll also have a strip of 1/8" x 1/8" maple on the shelf lip as a stop so the jars won't fall off and the back butts up against a wall. We run the vent any time we're using the stove so not sure how much moisture would play a role here. Based on the design I'd hate to have to add shelf bracing to the back.

Question
Do you foresee risk of the shelf from 1/2" thick sapele bowing across a 22-1/2 span with this little bit of weight ?

 

[pop-pop]

I’d worry more about the spices deteriorating from being near the heat from the stove.

 

[jfynyson]

I’d worry more about the spices deteriorating from being near the heat from the stove.

We go through them pretty fast, used on virtually every meal but good thought for us to watch out for

 

[gator]

The Sagulator is your friend.

The Sagulator – WoodBin

The front lip will add strength.

 

[jfynyson]

The Sagulator is your friend.

The Sagulator – WoodBin

The front lip will add strength.

Wow, I love this calc tool !....looks like my design will be plenty strong

 

[JNCarr]

I would think you want a uniform, not center load. This will make your sag even smaller.

Unless there's a button not shown, these calculators are usually based on a floating beam.
The through tenon will actually reduce the sag a little bit also.

 

[jfynyson]

I would think you want a uniform, not center load. This will make your sag even smaller.

Unless there's a button not shown, these calculators are usually based on a floating beam.
The through tenon will actually reduce the sag a little bit also.

I chose center load as worst case but good call out on the floating vs fixed. I chose "fixed" since it says "attached to the sides", which is what my mortise and tenons will do I think what is meant by "floating" is simply sitting the shelf on shelf pins. Either way this design is more than sufficient and shouldn't see any measurable sag (assuming the calc assumptions & calculator are accurate).

 

[JNCarr]

Yep - I missed the fixed/floating button.