Introduction: Poly Pot - the Polygon Root Pruning Pot

These Polygon Root Pruning Pots, or Poly Pots as I like to call them, promote massive root growth by allowing the root tips to come into contact with air. When root tips come into contact with air, they dry out and “burn”, signaling new lateral root growth. This effect happens when the root reach the bottom of the planter, and then again when they reach the sides. In most planters you’ll find the main tap root hits the bottom of the pot and all the roots just create a blob of a root mass at the bottom of the planter.

This design is meant to be modular, with the advance user being able to create custom size pots. There is also a slot for a soil moisture probe on each panel for those who wish to add automation to their watering.

Supplies

Something to plant
Soil
3D Printer (or purchase the parts)
Blade and snips to clean the edges of your parts
Low grit sandpaper

Step 1: CAD Models + Customization

With this guide, even a beginner in the 3D printing world should be able to complete using my pre-designed models. There are six “panels” that are assembled together with a “base” that fits inside the panels once folded closed. There are also six legs that attach into the base before assembling the base into the panel walls.

I’ve also have included custom “parts” for the more advanced TinkerCad users who may like to create a custom sized Poly Pots. I do plan on creating an expanded instructable to cover that process as well as adding automatic soil moisture detection and watering.

Links to the parts in TinkerCad:
Panels: https://www.tinkercad.com/things/1eFdtx91SBv
Base: https://www.tinkercad.com/things/jGOZGPnTVU6
Legs: https://www.tinkercad.com/things/hbH5sKFA4er

(Not required, but useful for checking your printer settings and tolerances on tight fitting parts)
Connectors only: https://www.tinkercad.com/things/iJzS6pmtfqt

Step 2: Getting the Files, Slicing, and Printing

This guide assumes you have access to a 3D printer and knowledge of how to operate it.

If you don’t, you can still complete this project by ordering 3D printed parts. There are various sources available. Once you’re parts arrive, move on to the assembly step.

For those of you printing this project yourself, you know your printer and slicing capabilities best. I like my tolerances tight, and therefore I had to use my exact-o knife more than I’d would have liked to. I will offer the following tips:

For the panels - just print them flat on their backs. I suggest a brim and supports (to the bed only) for 90 degree overhangs, which should only apply to one side of the hinges. They were fairly easy to remove, but I do suggest a light sanding with a fine grit to make sure the edge has a 30 degree angle (when two panels connected are folded into a hexagon, they need to be able to make a 60 degree angle. Any PLA blobs or material left from the brim will get in the way of proper folding). Be cautious when moving the hinges their first use, but they work themselves into a smooth action after a couple times swinging them back and forth.

For the base, I would avoid supports, it’s makes it a real pain to clean the rail the legs slide into. I’ve modded the design so there is no need for supports. 20% infill should be fine. I’d still use a brim.

Step 3: Assembling the Walls

When connecting a new panel, I suggest working it very slowly, to make sure there is nothing binding and keeping it from closing. Once you’ve swung the hinge open and close a few times, it has a smooth action.

You can either snap each panel into each other, or slide the barrel into the hinge and turn it. Once you have all six sides snapped together, you’re ready to assemble the base.

Step 4: Assembling the Base

Once you have the base and legs printed, you will need to slide the legs into the bottom of the base (the groove is located at the corners of the hexagon)

It may take a little work, depending on the tolerance of your particular printer and slicer settings.

Step 5: Putting the Base and Walls Together

Once you have the walls and base ready, lay the walls out flat (unfolded) with the flat part of the panel facing upward. Line up the three triangle at the bottom of the middle panel with the triangle protrusions of the base, and fold the rest of the walls around the base, lining up the triangles for each panel. Once all the way around, gentle snap the last panel connectors together.

That’s it, your done! All that’s left is to fill it with soil and plant something!