20mm PVC Conduit Adaptors

Like most of my designs, this came about because I needed something for my own use rather than thinking about what others might want. 

While setting up some home security cameras and automations, I had to run electrical and ethernet cabling along different structures. The standard shop-bought conduit fittings work fine, but they can be cumbersome to work with and look messy around corners and edges. Since most of my PVC piping is attached to steel square tube, I wanted one flat side to sit flush against the steel and a square inner edge to fit snugly over the corners. Additionally, the outside needed to be smooth and curved for easy cable feeding. The internal stopper for the PVC fittings sits about 25mm inside and has a chamfer on the inner side to prevent cable snags.

The adapters are designed for a snug fit onto 20mm PVC, and like most of my designs, they’re made for zero-support printing. I've found that occassionally they might print a bit too tight, especially if your settings caused the design to compact on the bed. In every instance, though, a light bit of sandpaper to the inner tube sorts it out. I recommend using PETG filament, with ABS or ASA as a second choice.

A note on printing these kinds of fittings in PETG: Bed orientation is so important for the final strength. If you print a connector flat on the bed you will likely split when inserting a PVC pipe as the layer lines will seperate vertically. The best orientation is on its side so that the layers wrap around the tube rather than run along it.

I’m designing these fittings as I go, so the range will grow over time. But if this design works for you and you need a specific fitting that's not here, just drop a message in the comments.