Nofty

A 3D printable, vertical NFT system. This is a re-circulating NFT (Nutrient Film Technique) system without any soil or buffering medium. Consumption of water and production of waste are kept to a minimum.

This whole set of parts comes pre-rendered as STL files. You can use these files in folder stl to feed your slicer and print them right away. If you feel the need to customize things, refer to config.js as good starting point.

Things you need:

3D printer
500g PLA or PETG filament
1x water pump, >5W
1x small tank, >3L
1x thin rope, <2m
12mm tube, <2m
fleece pad, 20x20cm

Things to know:

the pump should run constantly or at least in short intervals
make sure to adjust EC and pH values of your solution according to what you grow. to know the right values for your nutrient solution refer to this table.
as a general rule, plants will have a higher nutrient requirement during cooler months, and a lower requirement in the hottest months. Therefore, a stronger nutrient solution should be maintained during winter, with a weaker solution during summer when plants take up and transpire more water than nutrients.

How to print:

All my prints were done on a cheap FDM printer using PLA and a 1.0mm nozzle. The large nozzle makes prints really fast and sturdy. According to the 1.0mm nozzle, the WALL_THICKNESS variable in config.js was set to 2mm. Make sure you set your WALL_THICKNESS to a multiple of your nozzle width. Use at least 1.5mm or 2-5 times the nozzle width, depending on your nozzle. If you use a traditional 0.4mm nozzle, use at least a WALL_THICKNESS of 1.6mm to get enough stability. All pieces should be waterproof and fit into each other. The fit is crucial, so I recommend you follow the build instructions provided below to the point.

How to build:

print the bottom first, as it's the hardest piece. print everything from the bottom upwards.
now print one middle segment first and make sure that it fits into the bottom piece. if it does not fit, edit the config.js file and play with the value RING_INSET until you get a snug fit.
now go on and print the rest of the middle segments, up to 8 pieces or until you reach the max height possible with your actual pump. usually a stronger pump gives you more height and more flow, consuming more energy.
print the top piece. again, play with the TOP_DIAMETER value until it fits.
starting from the bottom, pull the rope through both holes on equal length.
now stack up all your middle pieces, always pulling the rope through.
pull both ends of the rope through the holes on the inside of the top piece and make a knot.

Printer Settings

use Layer Time when layers get to short, to allow the pieces to cool down and prevent deformation. if your prints are deformed, the chance is high that the pieces won't fit into each other.
get your extrusion right. use things like Fast edge over/under extrusion test on Thingiverse to adjust your extrusion and keep it consistent across all your prints.

Possible Features

Using pH and EC circuits from Atlas Scientific a constant measurement could occur
using an ESP32 the system could show pH and EC, be reachable through a web-interface and report its values to the cloud

How to operate

Once all parts are printed and fit into each other, you're ready to test your system. First of all you need to be sure there are no leaks. Even a small leak can result in a complete outage, when run for a couple of hours.

Note

This uses JSCAD v1 which is now deprecated. Upgrading to JSCAD v2 would mean to rewrite all models. I'm not gonna do that right now, as I don't see any resulting advantage.

bennyzen / nofty