Wanted to a make a model for the Coffee Corner contest here on Printables. I had an open space on the side of a cabinet, and after some rough measurements. I found that it could store a couple mugs on the side. So I made about 5 shelves, to hold 10 mugs.

The ‘base’ shelf is 235mm wide, 135mm deep and 145mm tall and holds mugs up to 100mm in diameter. This shelf also has a 2mm lip to help keep mugs from being able to slide off for any reason.
The ‘edge’ shelf is 241mm wide, 135mm deep and 15mm tall and holds mugs up to 100mm in diameter.
The back plate and base, for both models, are 6mm thick.

I used 4 M4 wood screws about 25mm (bottom 2 holes) and 20mm long (top 2 holes). Possibly overkill, idk I'm not an engineer XD, I just wanted more space to hold mugs outside of the cabinet ready for me to grab half awake in the morning.

This is a longer print and I delt with a fair amount of warping. I have printed a few shelves over multiple revisions. Every print had some warping, but I had the least warping with the ‘edge’ model, when using .32 layer height with a .6mm nozzle. I had sagging corners when printing the ‘edge’ model at .48mm layer heights on the back plate that is screwed to the wall\cabinet. The sagging is not too bad and the model prints fine otherwise. I would recommend doing .32 layer height for the ‘edge’ model and .4 with the ‘base’ model if you have the .6mm nozzle. The ‘base’ model does has a bit of warping as well towards the back plate of the model, but not to the point of detriment. I used 10% infill, but I believe you could get away with 5%.

Hopefully you find them as useful as I do.