Full constuction description (with tons of pics)
Alright, tronica, everyone, I'm finally 100% complete. This light is bad ass. 680w of dual spectrum greatness. I am using two separate ballast kits I bought from plantlightinghydroponics.com. I have a 430w hps ( $64.90 ) and a 250w mh ( $49.90 ). I needed to buy extension cords to plug them in, and also some extension #14 stranded wire to reach the sockets. And even with all the shady wiring I've done, I've only shocked myself once. Here's how I made mine.
Materials:
24"x36" Sheet Metal - Lowe's - $8
(2) 18" Strong Ties (thin) - Lowe's - $2
(2) 6" Strong Ties (thick) - Lowe's - $4
(2) Hurricane glass' - Michael's - $12
High heat white spray paint - Home Depot - $5
(8 ft) Chain - Home Depot - $4
(6) S-Hooks - Lowe's - $3
Nuts, bolts, threaded eyelets, washers all were from my junk drawer.
4" semi rigid ducting - My leftover drawer.
4" flexible ducting - Lowe's - (25') $18
(2) 4" rigid 90 deg ducting - Lowe's - $6.30
Duct Tape - Ace - $3
Galvanized steel wire - Home Depot - around $3
The total I figure I spent on it was ~$60. (i know if you add up the costs it's more than that, but I used some of the left over materials for other stuff)
All told with ballasts, bulbs, materials, tax, shipping I think it cost me around $260. Personally I think that is pretty good for basically 2 complete light setups with a custom enclosure.
Tools: (just a suggestion, you can use whatever you want)
1 big piece of wood with sharp clean 90 edges.
Gas Mask/ Ventilator (wear to spray paint, save your lungs for the pot)
48" ruler (at least 36")
2" pvc pipe (to bend the middle bend)
vice or clamp
big ass hammer (sledge if you are man, haha)
drill (some bits help too)
big roll of something like fencing or small tree trunk - anything cylindrical (to roll the curves out on)
sheet metal shears
Procedure:
The biggest problem I had with the whole thing was getting my sheet metal to come out right. There were two major parts to the sheet metal, the creases and the bends.
The creases I started by laying a big board on top of the flat sheet and trying to crease it by bending the edges up. This worked to get my creases started, but they were maybe 45 degree angles, not a very 'clean' crease.
To make the creases nice and strong I picked the board up and bent the creases with my hands over the edge of the board. This worked well.
To make the bends I tried many things, you guys really should have seen me. Just by pulling at it, I bent it a little, then what did the trick was wrapping it around my hardware cloth roll. And I just bent and rolled it as much as I possibly could, and it came out as you see it. At the most curled under pressure (while I was bending it) it more than overlapped itself.
For my design I had to cut holes in the reflector for venting to pass through. The reflector is pretty much exactly the size of my closet, and the venting had to get to the bulbs somehow. I just used sheet metal shears and cut the oblong hole you see, for the 90 degree rigid ducting to fit in.
I used the 18 thin straps on the underside of the reflector. This strap is what the bolts that connect to the chain go through and also what the heavy strap bolts to. They are also for structural support.
I bent the heavy straps to 90 degrees using a clamp (2 actually) and a sledge hammer.
I then painted the straps and reflector with high temp spray paint, flat white. I could have probably gotten normal spray paint, but why risk anything, especially for $1 difference.
I bolted everything together using pretty small machine bolts with locking washers. I used 2 to connect each heavy strap to the thin strap/ reflector. I used 2 machine threaded eyelets with locking washers for each thin strap to hold the thing up. And I used one extra screw to bolt the thin strap to the reflector. So for each side there are 5 bolts holding the straps to the reflector (3 bolts, 2 eyelet bolts).
The glass is connected using the Galvanized Steel wire. I just wrapped it around each end of the glass and stuck it through a hole I drilled, then made a loop to hold it in place. Simple. Also most of the rigidity of the glass comes from taping it to the ducting.
The 90 degree rigid ducting is just taped in place, the 180 degree semi rigid ducting as well just taped in place. I have the flexible ducting leading from the fan to the light and from the light out the roof.
The sockets are bolted twice each to the thick straps. I drilled two little holes for the socket wires to pass through the reflector. The wires leave the socket and goes in between the glass and the ducting (i just tape around them).
The bulbs I situated so that the first thing the fresh wind hits is the tip of the first bulb, blowing over the bulb, then the socket, making the 180 turn hitting the next bulb tip, then blowing over the bulb and out the other end.
My original plan was that the wind would always hit the 430w first, but I decided I would rotate bulbs to make the plants happy.
One tip a newbie will need when ordering bulbs. For best results use ED18 or T15 shaped bulbs, they are the skinny ones. Most others won't fit at all.
Results:
I have a 430w HPS and a 250w MH going. I have a 435 cfm inline fan (6" fan being forced to run through 4" ducts). With the fan collecting cool air (around 65 F) from the bedroom, the lights stay very cool (considering).
It is not that the 430w gets hotter than the 250w, but rather whichever is second in line for cooling is much hotter (duh). Even so, I can hold my hand on the first tube, and I can momentarily touch the second tube (it's kinda hot).
That heat dissipate quickly though as my plant tips have been at most 6" from the lowest glass for a week with both lights, no heat stress whatsoever. I'm more worried about light bleaching, but nothing yet.
Temps in the room stay around 80, but I do have a thermostat. However the room exhaust doesn't go off all the time, so the temps stay low.
If you have any questions I don't think Tronica would mind you asking. Not only did he give us this great idea, but he is gracious with his thread too.
If you haven't already give Tronica a +rep (you click on the scales on the top right of one of his posts)