Indoor autogarden - February 2016

Overall view of the system in the laundry/furnace room.  A shower curtain covers the front of the system to maintain humidity and provide a reflective surface for the light.  Note the water lifter on the left side.  

The shelving is made from standard adjustable  brackets on vertical supports screwed into wall studs.  There is a slight sloping of the upper shelf from left to right and from right to left on the bottom shelf.  The lights are hung from eye bolts screwed into the bottom of the shelf above.

A key element of this system is the upper part of the water chain.  Every fourth link contains a small bucket which deposits its contents into the center of the hub as the link moves over the hub.  Inside the hub there is a short path to an interior cone which directs the water to the outside of the hub and into the collector ring.  The collector is above a trough and the water comes out of the slots and drops into the trough once every revolution of the hub.  The rotation of the whole unit is by a small motor and a ball chain sprocket which works with a larger ball chain sprocket attached to the left side of the hub. Tubing goes from the trough to the first tray.

All of the pieces were designed by the author and fabricated using a 3D printer

Another view of the water lifter.  There is another hub at the bottom of the tank that keeps the water chain from floating and the two halves of the chain from getting caught on each other

The trays are made from 8 inch square storage containers that are connected to each other with short sections of rubber hose. I find that it isn't critical that the connections be water tight if another tray is placedbelow the first to collect water from any small leaks.  Small pieces of foam are placed in the lower tray to let the hose sections clear the top edge of the lower tray.

Within the trays are placed  pieces of foam that are about 7 inches square.  The foam is raised off the bottom of the tray with  5 decking screws (not shown).  Raising the foam prevents floating and provides a larger reservoir in the tray.  A cloth covers the foam and the edges extend down into the water below.  This serves as a capillary mat.  The pots and trays with the seeds and plants are placed on top of the mat.  If the holes in the bottom of the containers are not conducive to moving the water from the mat to the soil,a small wick or two (made from a paper towel) is placed in holes in the bottom of the container

Video is of a similar water lifter hub during development.

This post describes the first phase of the project.  In the next day or two I'll be adding a controller for the motor.  It will be based on a design that was used with great success last summer.  The outflow from the last tray causes a sponge to become wet. The weight of the sponge causes an electrical switch to be deactivated and turn off the motor.  After some time, the sponge dries out and loses enough weight to activate the switch and start the motor again.

Over