Simple question for building a wine rack

I am looking into building a simple wine rack for a friend as a gift. I’m trying to figure out the “optimal” size for the slots to accommodate most bottle sizes and maximize space usage as they live in an apartment.

It is a simple design pretty much just your standard X’s stacked on top of each other reinforced where/if needed to support the weight.

I was wondering if someone could suggest the maximum circumference I should keep in mind while building?

Thanks in advance,

~Winter

You may wish to ask this question in wine.woot!

Oops I somehow missed the other forum…moving post.

Here is a link with free plans.

Free Plans!

A good question to ask yourself is how many bottles you would like it to hold. Then do the math. There are all sorts of fun designs out there to chose from so good luck.