Cheap Filament Spool Rack / Holder / Shelf

This is my sit-on-a-shelf Filament Spool Holder/Rack. The pictured one uses 1/2" SCH40 PVC pipe. I've also uploaded STLs that should work with 1" diameter dowels (scale down slightly for 25mm?) and 3/4" PVC pipe. The STL suffixes say which file is for which (ex: _1_2_PVC= 1/2" PVC pipe). The pipes/dowels lie directly on whatever surface the rack sits on, so these printed parts are only providing bracing, not bearing weight. I heavily optimized them to use as little filament as possible: the three pictured parts were printed in PLA and weigh only 31g together (<11m of filament). The "v2" are the end pieces, you will need 2 of these per rack. For 1/2" PVC, you need to brace it every 24" or so, so if your rack is going to be longer than 24", then print one (or more) of the "v3", which are the center-tie pieces (last pic). If you use wood dowels, you may not need a center-tie. The center-ties look flimsy, and they are in almost every direction, but the only force on them will be tension trying to pull the pipes/dowels apart, for which I promise they are plenty strong. The center-ties are snap-on/snap-off, so you don't have to slide them all the way on, and they are low enough profile that a full spool can straddle one. I suggest using some hot glue to hold the end pieces on if they aren't a snug fit. These racks should work with most 0.5kg and 1kg spools.

Suggested print settings:

• Print in uploaded orientation.
• Hot enough for good layer adhesion.
• PLA, PETG, ABS, etc should all be fine. Using white looks nice with PVC. Wood filament might look nice with wood dowels?
• 0.5mm walls for all (assuming 0.4mm or 0.5mm nozzle).
• Print the "v2" end caps with 2 walls and 10% infill. I like cura's octet or cubic infill for this, grid/lines are in the wrong orientation for strength in this case.
• Print "v3" center-ties all walls, solid, no infill.
• No supports needed.

Tip: you can clean PVC pipe with acetone and a rag to get the printed-on words/barcodes off and make it shinier. Do this outside and let the rag dry outside.

Sort of inspired by this: https://www.thingiverse.com/thing:4061823, but I don't consider mine a remix.