Anyone printed one of those toilet paper guard covers for cats? Willing to share tips?

I printed one of these for the same reason, two cats who treat the roll as a playground. PETG is worth grabbing before you start. PLA will survive bathroom humidity fine honestly, it does not absorb moisture anywhere near fast enough to matter on a weekend timescale, but PLA gets soft around 60 degrees C and a cover sitting in a bathroom that also gets hot showers occasionally, plus being near a window with sun, can slowly warp. PETG is also less brittle, so if the latch gets smacked or dropped it bends instead of snapping. Dry the PETG filament first though, a damp roll will give you stringy mess all over that mesh. A food dehydrator or just a few hours in the oven at low temp works if you don't have a dryer.

For the latch, print it separately and orient it so the layers run crossways to the bending force, not along the hinge line. Parts like that snap along layer lines, so the direction matters more than anything. Add an extra perimeter or two, keep infill solid if it's tiny, and go slow. Honestly print two or three of them in one go so you have backups when one fatigues, they take minutes each. If the latch screws onto the lid, drill the hole slightly undersized or use a heated thread, because driving hardware into printed plastic too hard is what cracks them, not the latch itself.

The mesh sections are the real risk for a failed print. What kills them is thin walls printing with gaps or the top of each bridge sagging. Bump your wall count up, drop the speed on those areas, and make sure your flow is dialed in first with a small test print. Run a calibration cube or a single small piece of the mesh pattern before committing the whole thing. If the designer posted recommended settings in the model notes, use those, they usally know where the weak spots are. And do the long flat overhangs last if the model lets you split it, that part of a cover like this is where most failures happen.

Done this exact print on my machine a while back, ran the PETG at 245 and it came out clean. One thing the first poster missed is bed adhesion on a big footprint like that. A cover base that wide will lift at the corners halfway thru if you skip a brim. I use a 5mm brim on anything over about 15cm across, snaps off fine with PETG anyway. Also check the finished size in your slicer before assuming the model fits your roll, mine needed scaled up 8 percent beacuse standard rolls vary more than you'd think.

Funny timing, my cover worked great but my cat figured out the latch within a week and just flips it open now. Had to wedge a rubber band around the clasp to slow him down. So don't be shocked if yours are smarter than the design assumes. Also, before you commit the whole print, dry fit the latch hole against the lid piece if the model has seprate parts. I skipped that and mine was a hair too tight, spent an evening with a needle file fixing it.

Seconding the guy who said to dry fit the latch before committing. I printed one of these for my bathroom last winter and skipped that step, ended up having to file the hole out by hand with a needle file, took way longer than just test fitting a small part would have. Now I print the little hardware-facing pieces first while the big cover is still in the queue, so if a fit is off I can reslice before the long job starts.

I mostly print stuff for my aquarium stand so totally diffrent use case, but thin decorative panels burned me once too. Mine warped where the cutouts were and I never thougt about supports untill it was too late. Do those mesh holes need support underneath, or does the model print them clean? I'm still figuring out when the slicer is actually right about that stuff. Also my machine has a small bed, is this thing one piece or can you print it in sections and glue it? Might be easier for a first big print either way.