Thoughts on design?

Downsizing rom a 4x5 to a 3x3 sized box.

The current specs: 400w mh/hps with wing reflector, Poly Box 4x5 box . 4" inline with 4" carbon filter. Passive 4" intake. No ducting, just straight connections between the fan/filter and a small 5" long diy. duct to exit.

Current problems: Noise with fan on. Heat with fan off. Better fresh air flow. Better door.

Thinking of drywalling the 3x3. Build a box to house the inline (in hopes to silence the sound). Get insulated ducting (in hopes of silencing the sound). If budget allows upgrade to a cool tube? Mylar if budget allows? Or reuse panda.

Any critiques on the build idea? Suggestions or things to add/change?

are you talking in feet or meters? wrap that fan up in blankets old cloths anything then tape round it all insulated ducting defo helps dw about "will the fan get to hot with all the shit round it" iv done it a millions times one thing i like to do is buy a biger fan than i need then buy a fan speed controller to turn it down its so much quieter, cool tubes are good but the y steal like 20%?.. of the light imo anyways they just end up being shit that u dont use no more, get a decent fan u wont need cool tube if ur room is to small for wrapping up ur fan then have u fan outside ur room lay on fabric, cushions, cloths, blankets and then pile more of the same on top of it but remember the longer the ducting the more powerful fan ull need

i am doing something very similar in a box a little smaller in size. i am vegging right now under cfl's so i am using a pc fan to exhaust so i dont have to worry about temps at the moment. but i will be getting a 4 inch inline fan/filter combo and im getting the lumatek ballast that runs a 250 or 400 watt hps and plan on running it on the 400 setting. but i plan on getting a cooltube also attached to the 4 inch fan probably by a T. I would definately say you should try and get a cooltube or an air cooled hood if possible because it is going to be hard to keep temps down with a 400 in a 3 x 3 without one.

as far as sound, the best thing to do with inline fans is to hang them from your box by bungee cords because they seem to vibrate if mounted with the brackets. so i would try that first because it is cheap and easy. some good ducting might help as well. you can get some cheap 4 inch dryer ducting at home depot u probably don't need insulated ducting its expensive and hard to mess with.

for the door, an easy thing to do is velcro up a piece of panda film for the door keeps it sealed and light tight.

but i would suggest get a cooltube and connect it as i mentioned above. you can grab a cooltube for around $50 on ebay.

i never used a T with the cooltube just put the can and fan on the same length of ducting as the cooltube

I wanted to do a solid, drywall door. Would that be possible? (how would I do that). I think a fan controller + insulated ducting should deal with the sound problem. Plus the thick-board box to hold the fan, also suspended with bungies.

Depending on budget a better reflector, or maybe all around upgrade 400 to 600w? My question is how much of a difference is it in; heat? flower/quality? Detectability (to heat sensors)?

Joint Monster said:

I wanted to do a solid, drywall door. Would that be possible? (how would I do that). I think a fan controller + insulated ducting should deal with the sound problem. Plus the thick-board box to hold the fan, also suspended with bungies.

Depending on budget a better reflector, or maybe all around upgrade 400 to 600w? My question is how much of a difference is it in; heat? flower/quality? Detectability (to heat sensors)?

Click to expand...

Yep fan controllers do seem to be the easiest way to keep the sound form inline fans down. a lot of people are getting 6 inch inline fans and running them at 75% with a speed controller instead of running a 4inch at full speed and its supposed to be a lot more quiet.

You could do a drywall door just hang it with some hinges and put weather stripping around the edge of your box where the door closes on so it will stay light and air tight. but how you hang the door all depends on how you built the box. I am going to make my door the same way a regular bedroom door is hung in a house because it is easy to keep it light and air tight. I used 2X2's to frame my whole box first so where the door goes I have 2X2's flush with the edge that will act as my door frame. Im then going to attach some wood stripping about an inch deep (or however wide my door panel is going to be) on the 2X2's all the way around the doorway with some weather stripping on the wood strip as well. that way my door will close onto the wood stripping which the weather stripping will keep it light and air tight and the door will be flush with front of my box when closed.

as for the lights, I haven't used a 600w but I would think there would be some more heat but im not sure how much more. and a 600 watt light is supposed to be the most efficient when it comes to the lumens put out per watt compared to a 400 or 1000 watt hps.

i usualy only ever use 600 watt lights there alot of hotter then 400's, realy you need to leave 4,5,6, inch fans alone there not powerful enough imo unles you run them full power so there rly noisy, get an 8 inch fan covored in blankets with a fan speed controller then u can grow all thru summer no problems or up grade your lights to 2 and easily keep you grow the temp you want it