I recently built such a rack. I made it out of 3/16'' angle aluminum (L
shaped cross section). Looking back on it, I probably could have gotten
away with 1/8'' thick Al. The rack is about 4' by 2' and has 4 levels.
If it wasn't for a few tall plants, I probably could get 5 levels out of
it. I bought wire closet shelving at a local hardware store to support
the plant trays and my fluorescent shop-lites hang down from the
shelving on the level above. My big problem was in finding trays to set
the plants in. Ideally I wanted welded aluminum trays that could be
bolted into the rack but they were much too expensive >$100 each. The
solution was to get the plastic covers for flourescent lights (the
recessed type) you see in office buildings. These are plastic trays
that are 4'' x 2'' so they are perfect in size but a bit flimsy. I have
added shades to the rack partly to serve additional reflectors and
partly to keep the light out of my eyes should they be on while I am
sleeping -all of my plants are in my bedroom. The next addition to the
rack will probably to put plastic doors on it to try to get the humidity
up. I have used brass bolts to fasten everything together and it looks
nice against the aluminum.
One advantage of the L shaped angle aluminum as opposed to the square
crossection is that when the rack is disassembled, the pieces nest
together and don't take up much room. When I move, I can put the entire
frame in a ski box and send it in the mail to my next destiniation. I
should save some money on the postage because the Al is much lighter
than steel (although it is significantly more expensive). Really my
main reason for choosing Al over other materials was that it is easy to
work with and doesn't rust. Some of the extra cost is recovered because
it also does not need painting.
> My ingenious idea (pat. pending) is to use PVC plastic tubing
> and joints to make a frame to suspend, or support, the light
> fixtures. I've used PVC before to make a greenhouse in the late
> 1970's, and it's a quick and easy way to make almost any
> strcture. It can be painted after you've glued it up to make it
> asthetically pleasing. And it's cheap. I may try it out over
> Xmas vacation if I get ambitios and have some spare cash.
For the top shelf on my rack (6' above the floor), I plan to suspend the
fluorescent fixture from the celing. This might work for you although
you would need long chains.
If you are considering building some sort of indoor light rack I would
recomend looking at a 30 page booklet put out by the Indoor Gardening
Society (of America?). I bought it for about $3 from the American Orchid
Society. It has lots of tips and also contains about 10 designs for light
racks that people have constructed. One of the more interesting ones was
sombody who converted their fireplace into a plant growing area.
Scott