DIY: Best Cool Tube

Discussion in 'Do It Yourself' started by Mystic, Nov 1, 2007.

  1. I had to share these instructions...the best I've found!

    Clean, Easy Cool Tube Tutorial
    <HR style="COLOR: #258c25" SIZE=1>(*Note - This is of course, by no means a new idea. This is simply meant to be an informative tutorial based on my experience while searching for a cool tube solution. I was unable to find any detailed or clean instructions on how to make a cool tube using a Pyrex bake-a-round. They all ommited small details or used a ton of duct tape, random scraps, etc. This is intended for those who want a durable, clean, easy to assemble piece of equipment for thier setup. )

    Clean and Easy Cool Tube

    This is a detailed tutorial on how to put together your very own cool tube. You can assemble one of these in about 20 minutes. This is based on a 150 watt HPS, but may be adapted as needed.

    What You Need:


    1 x Pyrex Bake-A-Round tube (long discontinued, but available readily on EBay and in classifieds, Flea markets etc – surprisingly common) - $10-15
    1 x pair of Café Rod brackets (hardware store, where window fittings are located) - $1.50
    1 x Ceramic medium or mogul lamp base with standard mounting hole - $0.99
    1 x 1”-1.5” (approx) hose clamp - $0.80
    1 x 3.5”-4” (approx) hose clamp - $1.00
    2 x 4.5”-5” (approx) hose clamps - $2.50
    1 x roll of self adhesive insulting foam for hot water pipes. - $2.50
    1 x #6 – 32 x 3/8” (machine screws with nuts) - $0.99
    1 x multipurpose (including glass) glue or epoxy (optional) - $3.00
    1 x 400F small tube of silicone sealant - $2.50
    Your HPS/4” duct system – N/A

    Step 1:

    Collect your café rod brackets, lamp base, and screws.


    Remove one of the café rods and bend into roughly the shape illustrated in the next photo (you may need a something to help such as a pair of pliers).


    Attach the café rod to the lamp socket's mounting hole using a screw and nut.



    Connect the wires from your power source line to the lamp socket. The white wire should connect to the silver screw, and the black wire to the brass / darker screw (this is standard color coding). I used a little bit of solder for good measure. Leave the ground wire (green) unconnected for now, ideally left a little longer than the others.
    Cut and bend the remaining café rod into three pieces with tabs on the end as shown. The longest/middle section should measure 1&1/8” on each (medium) or 7/8" (mogul). The other sections are of negligible length, but around ½” is good. These are your spacers.


    Fasten the spacers to the lamp socket as shown. Use your epoxy or glue if desired in addition to the clamp to make sure everything is firmly in place.


    Step 2:

    Hang your bulb assembly over the end of the Bake-a-Round. You will notice that there is a slight bit of play between the spacers attached to the socket, and the inner walls of the tube (if you measured correctly and don't have an oddly sized socket). This is deliberate and is to account for possible thermal expansion in the metal. Fitting the spacers firmly could result in a cracked or broken tube!


    Place the bulb in the socket and clamp the hook hanging over the side of the glass tube with the ~4” Clamp. Tack the hook and clamp with epoxy/glue for added strength (The glued clamp can still be popped off, so don't worry too much about how you will change the bulb).


    Step 3:

    Wrap self adhesive insulating foam around each end on the tube as shown (or only one if you are using exhaust only). This will allow 4” duct to fit very snugly to the tube (which it's self is 3 ¾” O.D.), and will also act as a gasket/seal when clamped.


    Thread wiring through the ducting, attach the ducting to the tube, and clamp in place. Finish with silicone sealant if desired. Connect the ground to the duct or the café rod hook.


    Add an optional reflector made from unclosed rigid duct (you can find this in your hardware store – it's a piece of sheet metal with a snap together seam that hasn't been connected). Simply cut to length, cut flanges a half inch from the ends, and clamp those to the duct/tube. Hang your lamp with light chain available from your hardware store by the foot. The chain attaches under the clamps on the duct. You're done!

    • Like Like x 1
  2. Nicely done, thanks for posting!

  3. Great post,

    only thing i would ad : go with a 6" diam. if possible (they do it comercialy that way for a reason ;) )

    this one is 1000000000 times better than the plastic one i saw earlier.. haha
  4. the only probelem is those bake-a-rounds are a pain in the ass to find. you can use hurricane glass too if you cant find the pyrex
  5. The bake arounds are all over ebay...usually around $20 USD to get one to your door. Ok, maybe not all over, but usually can find a dozen or so at any one time.

    Peace - OGH

    ps- I've heard flea markets as well for finding those things...but never tried there.
  6. i couldnt find them on ebay the last few times i looked. probably one of those items you have to keep lookin fore
  7. wow i just checked and thers a grip my bad
  8. Thanks for giving me credit for my write-up...wait nevermind. PS, I have already posted this tutorial here under this name.

    Take care,

  9. This was taken from Lemon on that your handle there??? If so, mad props to you...if not, then...
  10. Sorry bro...for some reason I did not find this using the search option. and it was weird too, because I initially thought I had found it on here, but then I couldn't find it, but then I found it again on totally my bad bro...totally my bad.

    I didn't know who to give credit to from here, but now we do...

    All hail the cool tube master...duckfool, aka lemon...what other nicknames do you have bro? Again, thanks!

    One thing I found on another site was that someone has put a carbon filter BEFORE the concerns with this were that it would be pulling warm air from inside the cab through the cool tube...would this be affective enough you think?

    Anyhow, here's THE MAN's original link...

    Or maybe, just maybe duckfool copied from Lemon and didn't give him credit? Guess we'll never know for sure.

    Either way, I was pretty clear that it wasn't I hope there's no hard feelings.

  11. Whats the diameter of that pyrex tube? doesn't look like it'd be wide enough for a 400 or 600w light....

    Nice job for a cab gro tho !

    its 4 inches wide, not big enough for a 400w metal halide.
  12. I'm running one on a 400 watt HPS, and I have 400 watt MH bulb that would have no prob fitting inthe cool tube. Just avoid the "fat" bulbs.

  13. No balast needed for 150 watt HPS?? Could ya use a 400 watt bulb w/ that as well w/ no balast? Sick idea though.. Nice way to save like 40 bucks.
  14. Just kidding, realized thats what you plug into the balast.. lol
  15. very sweet man! + rep
  16. I bought a bake a round years posted to Aus too! Maybe its about time I put it to some use....and I ain't making bread!
  17. thats sweet! do you think i should blow a 250 cfm in through the semicold attic and vent outside or blow in the 20 degrees fahrenheit air outdoors and vent into the attic. 1000w mh and hps in a 5'x5'x8'.
  18. where could i get a six inch diameter tube. anybody.
  19. Bumping this thread with a question for mord.
    Where do you find them with 6"diameters?!
  20. I was just commenting on the fact that he should use a 6" diam. if possible,

    I dont know that there are 6" bake a rounds (or what ever they are called)

    my cool tubes are 6" , and it seems like 4" may be harder to cool (less air volume), thats what promted me to post anyway.

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