150w HPS Club and Resource Guide......

[greenhead]

Just take a look at the dba rating when you buy a computer fan, that'll help to keep away from the noisiest fans at least. But, just because two fans have the same dba rating, doesn't mean that they are the same in terms of noise. They might make a different kind of noise (one might make a high pitch, while the other one might be a lower sort of hum), making one of them more annoying than the other. They might run at different RPM's, etc.

I use three computer fans inside my cabinet, 1 that's blowing between the tops of the plants and the light, 1 that's blowing on the top of the HPS vents, when I use the HPS, and 1 for exhaust. I use a speed control for the exhaust, so that I can turn it down slightly at nighttime, when lights are off and it's cooler, that also makes the cabinet much quieter when lights are out.

My exhaust fan is still louder than I would like when lights are on, and I'm looking into other kinds of fans that make less noise. I'm trying to make my grow cabinet as stealth as possible, and that means virtually no noise.

 

[namo420]

greenhead..you should look into sound proofing materials,a little expensive,but works well

 

[greenhead]

greenhead..you should look into sound proofing materials,a little expensive,but works well

Thanks for the tip ! I don't have the budget right now to upgrade anything in my cabinet, but I will in the future sometime. I am aware of the different soundproofing materials that are available, since I was recently researching some acoustical dampening material for another project that I was recently working on (not marijuana growing related). I've been trying to build a small vocal booth for my little home studio. I found out that there's even an acoustical paint that dampens sound somewhat. But you're right, some of those acoustical sound dampening materials are pretty pricey.

 

[Arcane]

DC, 2100 rpms, 38Db, is that gonna be noisy? It seems that the low rpm would be a hum, am I correct? The standard 35cfm ones are 25db and 3500rpm.

 

[eLiguL]

I use to have a CPU fan rated at 38dba and it would keep me up at night. Sounded like a plane turning off when I powered down my computer.

 

[greenhead]

As far as db(a) levels go, this is my understanding at least, somebody correct me if I'm wrong.

A 33 db(a) fan has twice the sound intensity as a 30 db(a) fan. However, due to the way that the human ear perceives sound, around a 10 db increase is required for a sound to be perceived as twice as loud. So, in other words, a 40 db(a) fan will sound about twice as loud as a 30 db(a) fan. A 20 db(a) fan will be half as quiet as a 30 db(a) fan.

If there's two fans running, and each one has a rating of 30 db(a)'s, then the combined sound level will be 33 db(a), and not 60. Four 30 db(a) fans all running at the same time would give a combined total db(a) level of 36.

When it comes to computer fans and noise though, it's really up to the individual person who's going to be near them. Some people don't seem to mind things that are a little noisy, while others do.

 

[BoB91]

Good evening everyone. I wish I could partake in all the technical discussion but I can not. I am neither technical or a diy kind of guy. I dont grow in a cabinet just in a huge walk in closet in a corner. I am sad to say that both of my sdogbx were males but both of my mmm#2 are female. I have two different plants I beleive. I topped one and the other is really reaching for the light.
This is the top of the tall one.
My gypsy gum is coming along. Starting to frost up a bit. However there is really no smell(thats a good thing since I have no odor control)

 

[Arcane]

Nice progress BoB91, I envy your walk in closet!

 

[BoB91]

Thank you but trust me there really isn't anything to envy in my closet except maybe my three plants. Even then that is a stretch. I just hope these finish soon because I need some smoke bad.

 

[DrHydro]

Everyone has to start somewere..

 

[Pipedream]

OK, since we're talking about sound, I'll put my 2 cents in. It's a field that I'm intimately familiar with and has been my main source of income for more years than most of us have been on this earth.

Greenhead is on the money. Sound measurements are a logarithmic scale. Every 3 db is a half power point, but not to the human ear. Also, those db ratings will do little to tell you what it will sound like after its installed. Ever listen to a speaker outside of its speakerbox? You can hardly hear it in comparison. Your cabinet or ducting is one huge reverberation chamber. Just moving your fan from one end of a duct to the other can have a dramatic effect and more often does than not.

As far as sound-proofing material goes, there are basically two distinct applications. Either to stop echo and reverberation, or to stop transferrance. (sound passing thru a wall) For echo and reverb, "eggcrate", soft surface, or non-parallel surface material is used. Such as in the recording studio or voice-over booth. It must be used on the inside surfaces and has no place at all within a growing set-up. The only two things that stop transferrence are mass and isolation. Isolation is both expensive and impractical. When I worked at Bell Labs in the early 80's they had an entire room suspended in a another chamber by rubberbands. Worked great, but cost millions. Mass is the most common method used in construction. The product I've spec'd out the most over the years is lead-lined sheetrock. Expensive & heavy as hell, but I never had to move it, just draw it on blueprints and post it on the material list. The cheap alternative was always a sheetrock & Wonderboard sandwich. Anyone could afford it and they still use it for home theaters. The problem with mass is.....it also insulates the heat within the area. This can be a real concern for a small grow space with maximum lighting going. Especially if its the heat you are trying to address!

So where am I going with all of this? In short there is no easy answer. A lot of it will have to be trial and error, just as it is in the real world. We design it, they build it, the client complains, and we modify the plan and start over. As far a where to start goes. Do what many engineers do....take a SWAG. (sophisticated wild ass guess).

Please excuse all typos, as I just finished a rather large bowl.

 

[eLiguL]

Great explaination of sound there Pipedream.

I have finally finished drafting my cab design and was wondering if anyone has any insight as to which material I should use for it. I have narrowed it down to either spruce plywood or particle board. The plywood is cheaper but the particle board has a smoother finish. I have seen many people use plywood for their cabs but have yet to see anyone use particle board and was wondering if there was a reason for this?

 

[DiscoDuck]

Pipedream is dead on about various fan/air noises and how grow box/ducting amplification can combine for unwanted noise. I tried mounting one of those 120vAC server fans to the inside wall of my box. Air noise was minimal as was air transfer but the mechanical and electrical noise transferred to the grow box. I even used rubber isolator material between the fan and the wall to no avail. I picked up one of those LASKO blower fans at Walmart for about half the price of the server fan and it moves three-times the air, (on low speed!) I krazy glued a couple of plastic 3" ducting collars to both fan intakes and attached 3" ducts to the grow box. On low speed I can barely hear air movement and that nasty grinding noise is a thing of the past. Walmart doesn't list this fan on their Web-site but here's a link from West Side Wholesale:
http://www.westsidewholesale.com/in...t_order=sales&pid=974812&CATEGORY=643&back=16

 

[greenhead]

So where am I going with all of this? In short there is no easy answer. A lot of it will have to be trial and error, just as it is in the real world. We design it, they build it, the client complains, and we modify the plan and start over. As far a where to start goes. Do what many engineers do....take a SWAG. (sophisticated wild ass guess).

Please excuse all typos, as I just finished a rather large bowl.

Great explantation of sound Pipedream ! You worked at the same place where dB got it's name from, cool ! Taking a SWAG is a good idea, but I usually take a BONG hit first, then a SWAG.

 

[DiscoDuck]

eLigul, particle board is pretty popular and you may want to consider a couple of things:
Medium density (MDF) is probably the most popular but it has to be reinforced so as not to strip the threads of screw holes, stress points etc. If you ever have to move your completed grow box you'll have to be thorough with construction methods. Have you ever seen a cheap MDF computer or stereo/tv stand fall apart when it is moved?

High density (HDF) is stronger than MDF, doesn't require as much interior bracing and can be moved from time to time with less risk of disaster. HDF is harder than MDF. Screw holes probably should be pre-drilled so screws will pull straight and be less likely to strip. HDF is almost impossible to sand rough edges and surfaces unless you have a power sander with rough-grit sand paper.

Another consideration is thermal: not sure which material retains the most heat I'm using an MDF audio cabinet covered with some kind of protective fabric. The two combine to make my temps run a few degrees hotter than say 1/2" plywood alone.

To make things short I'd pay a little extra and get 1/2" plywood with one good side, A/B or B/C grade. This will give you a nice exterior finish with minimized exterior finish/labor cost. It doesn't really matter if the inside is a little unfinished, you can always paint it flat ceiling white or cover it with reflective mylar. You don't have to go crazy with bracing with 1/2" plywood. It's as strong as you'll need for a grow box of 150w hps proportions.

If you happen to find out which material absorbs less heat, please post it in this forum.

 

[greenhead]

The plywood is cheaper but the particle board has a smoother finish. I have seen many people use plywood for their cabs but have yet to see anyone use particle board and was wondering if there was a reason for this?

My cabinet is particle board. It was just a cabinet that I found at a target store, and the dimensions were right for me, and so was the price, so I bought it. I don't have any car, so I had to schlep it on the subway, carry it home, and it was heavy as hell, damn near broke my back. A few pics of the cabinet can be seen in my first grow journal.

 

[Thief]

hi all! i'm not new here, but this is a new account.

my DWC buckets were working fantastically up until a couple days ago. the plants went from this:



to complete shit in a matter of two days. they went K-def, then the leaves got really skinny and yellow, starting at the bottom of the plant, then they fell off. i have no idea how to explain it except to say that maybe my water temps were way, way off at that point. the weird part is the very top leaves stayed at a 45 degree angle, like they were doing fine. but the entire plant went def and i had to cut her down. ph/ppm was kosher all the way through. i'm going to go for a winter re-try on the DWC, when the house isn't so plunderingly hot all the time.

you know what they say. you have to kill a couple plants before you become the master 1337 grower. hehe. poor plants.

i have since switched to 100% coco, hand-watered. i'm waiting on more speed queen cuts, but there's a new sativa plant in the flower box ready to go as we speak. more pictures soon, i suppose, when she's finished stretching and has settled in from her transplant.

it's good to be back.

 

[eLiguL]

eLigul, particle board is pretty popular and you may want to consider a couple of things:
Medium density (MDF) is probably the most popular but it has to be reinforced so as not to strip the threads of screw holes, stress points etc. If you ever have to move your completed grow box you'll have to be thorough with construction methods. Have you ever seen a cheap MDF computer or stereo/tv stand fall apart when it is moved?

High density (HDF) is stronger than MDF, doesn't require as much interior bracing and can be moved from time to time with less risk of disaster. HDF is harder than MDF. Screw holes probably should be pre-drilled so screws will pull straight and be less likely to strip. HDF is almost impossible to sand rough edges and surfaces unless you have a power sander with rough-grit sand paper.

Another consideration is thermal: not sure which material retains the most heat I'm using an MDF audio cabinet covered with some kind of protective fabric. The two combine to make my temps run a few degrees hotter than say 1/2" plywood alone.

To make things short I'd pay a little extra and get 1/2" plywood with one good side, A/B or B/C grade. This will give you a nice exterior finish with minimized exterior finish/labor cost. It doesn't really matter if the inside is a little unfinished, you can always paint it flat ceiling white or cover it with reflective mylar. You don't have to go crazy with bracing with 1/2" plywood. It's as strong as you'll need for a grow box of 150w hps proportions.

If you happen to find out which material absorbs less heat, please post it in this forum.

That was very informative and thank you for taking the time to write it. Ill have a look to see if they have this higher grade plywood at homedepot, if not ill just sand it smooth I suppose.

My cabinet is particle board. It was just a cabinet that I found at a target store, and the dimensions were right for me, and so was the price, so I bought it. I don't have any car, so I had to schlep it on the subway, carry it home, and it was heavy as hell, damn near broke my back. A few pics of the cabinet can be seen in my first grow journal.

Thanks for your post I didnt realise that particle board was that heavy.

 

[Lemon]

I have seen many people use plywood for their cabs but have yet to see anyone use particle board and was wondering if there was a reason for this?

My cabinet is made of particle board/MDF. I can't see an overwhelming reason to chose one over the other aside from cost. I like MDF because its smootther/cleaner looking and can be bought with a melamine laminated surface in various colors. Plywood will hold fasteners better.

particle board cab under construction:

 

[DiscoDuck]

Everybody reading about this mdf vs. plywood stuff, check out greenhead's mdf cabinet from target. His plants in there are SMOkin!