Need Help 250W Cool Tube

When working with the hurricane glass "chimney," the irregular shape needs to be overcome so that it can be attached it to a reducer collar that will make up one end of the fixture. You may attach a reducer collar to a single end if you want an open ended design, or you can attach one to each end if you will be running ducting to both intake and exhaust ports.
The graphics concentrate on the exhaust end to which the bulb socket is also anchored. On this end of the glass (at the narrow "throat") numerous wraps of thermal pipe wrapping are wound around the glass and secured with a couple of wrappings of foil duct tape. The wrapping should build up the throat to the same diameter as the opening in the glass - where it snugly fits inside the larger end of the reducer.
This will allow us to use a 5" hose clamp to secure the edge of the reducer collar to this tape wrapped "cushion." (Note: you can use foil tape alone for building this "cushion" but the thermal wrapping makes for a neater seal, and is less susceptible to heat. Also, if a hose clamp isn't available, the reducer can be secured to the glass with foil tape.
If you use a hose clamp, you will need to make some 1" slits in the edge of the reducer collar the glass fits in to allow the hose clamp to compress it enough to hold the glass securely)​

In the graphic, a length of pipe strapping bent in a "U" shape is used to hold the socket far enough inside the glass to place the bulb roughly in the middle of the glass. This glass, $3.99 at Hobby Lobby, is 11 3/4" long and 4 5/8" at each end. Notice this glass is symmetrical. Don't try to use the asymmetrical hurricane lamp "chimney's" available at Lowe's or HD; they're too small and aren't shaped in a way that permits good air flow. The socket is either screwed or pop riveted to the bottom of the pipe strap "U." My light was made from a 150w HPS security light which used a "medium" base socket; this socket has two little screws in it that more or less lined up with the holes in the strapping. As for the mogul base sockets used with bigger lamps, I don't know what they have on the bottom of them so you may have to improvise a solution for mounting them. The ends of the strap are bent around to "clip" over the edge of the glass and then secured with a couple of wrappings of foil tape. If you'd like, a more permanent mount can be had by drilling a couple of small holes in the tapered throat of the reducer and attaching the ends of the strap with a couple of pop rivets.​

(NIMBY) "Using a Pyrex (borosilicate glass) tube obtained from a glass blowing supply house or using a "Bake a Round" (eBay had a dozen for sale the last time I checked) one utilizes either one or two (pictured) 4" starter collars instead of the 5" to 4" reducer collars. They are 14" long and 3.75" in diameter." "I stretched the aluminum ducting out and measured 16". I then snipped the metal "ribs" and cut the ducting open. The glass tube will just drop into the long run of ducting. The electrical wires run to the remote ballast through the intake part of the duct (exhaust could also be used depending upon the location of the ballast). I measured 2" from each side of my original cut and snipped the metal ribs again but this time didn't cut the aluminum foil. This allows me to open the ducting up like a "wing"."
A couple of wraps of pipe wrap sealed with foil tape on each end you want to put a collar on should be used to keep from biting the metal directly into glass with the hose clamp (pictured). The socket is mounted inside the tube with pipe strapping just as in the hurricane style fixture. It can either be "clipped" and taped over the edge of the glass or better, pop riveted to the inside of the starter collar. Simply stick the glass inside the end of the starter collar an inch or so past the bottom of the tabs to measure how far in to drill two holes 180 degrees apart, then use two pop rivets to attach the strapping A note about pipe strapping; don't get the thin wimpy stuff. Get the thicker heavy-duty strapping. The heavy stuff is still relatively easy to bend but holds its shape better and will hold the bulb and socket straight without sagging. At Home Depot they even have some copper pipe strapping (also known as "pipe tape" or "pipe hanger") that is quite stiff.​

There are many different ventilation options available, since standard household ducting is used in the construction of the fixture. For those folks with bigger boxes or rooms, ducting in and out, "inline" duct fans are probably the best option. For my little NewGanjaBoy-style setup, using the Hurricane fixture as part of the ventilation system of my box, a 115cfm computer fan does the trick. As for actual performance specs for different blowers/fans and light wattages, I'm afraid you'll have to experiment. Here's mine just to give an example:​

Ambient temp: 80°F Flowering chamber 1 hour after HPS fires up: 95°F (in direct light) Flowering chamber 6-12 hours after HPS fires up: 100-105+°F (ouch!!)​

Ambient temp: 80°F Flowering chamber 1 hour after HPS fires up: 85°F (in direct light) Flowering chamber 6-12 hours after HPS fires up: 90°F (in direct light)​