Need help with PC Grow

I tried to add this to the PC Grow Gang section, but it would only allow 1000 letters.

Hello PC Grow Gang,

As some of you may know my second grow was so hopelessly stunned by heat issues that I had to forfeit for cutting times sake. I have since then been contemplating on salvaging the PC towers and build a small grow box.

However, with insufficent funds to build a box right now I have converted back to the method of my first grow within the towers. They are now 12/12, only running at night, only running 2x 30w, but so far have been running quite smoothly. I have some bag seed a couple inches tall right now, which has made me rethink the box plan a bit.

*I don't know if it is a sense of pride but it is like hating losing or the feeling of unavailability*

The good news is I might have saved my units from disassembly since I over stocked from the start. I have several pc fan units lying around the house from when I first bought the cases. After a good pep talk from one of the most valued PC Grow Gang members he gave me a good idea. I have never tried to do a cool tube. I have, however, set up some plexi glass, which helped the heat a little bit, in my first grow. Noticing that I had enough fans for both units to hold 4 fans my brain started sketching up some plans.

I was planning on putting a cool tube in my small grow box, which gave me education on how well it works and then v12 suggested it to me via pm for the PC units. If workable this would also free up my 5inch fans to be used in the small grow box.

The plans are a tid bit sketchy right now, but hopefully with some of your guys help I can get them heat proof finally. So the idea is to build two side walls with a fan hole at the top and a fan hole at the bottom. I am thinking about putting the intake fans on the outside of the wall blowing in. These fans will be covered by the face plate of the PC units. After wiring them up I will establish the back wall with like holes. I will have 80mm fans for intake and exhaust for the cool tube (is this good?). The bottom fans will be 1x 80mm fan for intake and 1x 120mm fan for exhaust (I can switch out the 120mm with the top 80mm exhaust if need be). One major question I have about the fans are on the font they say 5v and I only have 12v chargers. I am wondering if this will be risky in any way?

I will need another piece of plexi glass to cut, but I do have the know how now. Another thing I need to alter would be my 'shelfing' unit. Currently I am just using stacked DVD cases which fill up my unit to the walls at two cases sideways. Any suggestions?

As for visibility I am going to have to reconstruct some light traps, but the genius v12, offered me a product that I was able to take out of context. http://www.dansdata.com/badong.htm The basic idea is like the end of this product it has a scoop. If applied in a more 'boxy' shape it can be used as a light trap. I should only have to build two of these for the cool tube exhausts. As for the bottom exhausts a fabric softener should be sufficient.

The good news is that this little deviant should only require; foam board for new walls, tape for making the plexi glass air tight, plexi glass, and shelfing system maybe. This is a low cost for being able to maybe get another 30w in there and/or having a constant low temp chamber.

Please let me know if you guys think this is a viable option and a good one. The temps are slowly rising and I believe that summer will bring increased temps for my current 12/12. Right now the highest they have got is 86F, but I don't know if it'll last to be honest.

-X

If at first you don't succeed, don't try skydiving
Great to see you back at it Xan.
I'm with you on the 1000 character thing, that's why I keep banging the drum about a pc growers subforum in ER's request thread.

I've just done a bit of a general brain dump for you. It's in no particular order but it might stimulate conversation or ideas.

A couple of myths to bust first:
Auto strains are perfect for a pc grow.
Wrong.
Auto strains do only grow to 16 inches or so, so they should be perfect but in practice they are a poor choice. While they may be small, every single auto strain I have tried has stunk the place out. In covering up the smell I need lots of odour proofing on my fans and that makes my fans virtually useless. End result is that the plants get too hot and die. On the lucky occassions when they do finish flowering, the bud is average at best.
Regular strains offer choices that include small stature, high potency and odour free plants.

The new silent fans are perfect for growing in a pc case.
Wrong.
Silent fans achieve their quiet rating by not spinning very fast and so they don't move much air. When temps rise or odour control is required they become practically useless.
Best option is to find a fan that runs faster and noisier so it will move enough air to cope with summer temps, then turn down the voltage when you don't need odour control or lots of cooling and they will naturally become silent. You can then grow all year round.

Something else to remember about hot air is that it is less dense than cold air. This directly affects pc growers because all the air in the case is hot. This means that even though the fan is capable of moving say 50CFM of air it will only actually move half that amount because the fans are tested at 68F, not 78+.

Some heat coping strategies:
Indoor seeds have been bred and acclimatised for 78F but outdoor or landrace strains are capable of surviving hotter and drier climates, so consider these for your summer pc case crop.
Does the top of your case get warm? If it doesn't then think about moving your lights closer to the top. The case itself can be used as a huge heatsink. All hot air inside the case has to be removed by the fans but if some of that heat is transferred to the top or side panels of the case then it can dissipate directly into the atmosphere thus reducing the load on the fans. This is the ultimate silent cooling technique.

Matching intakes with exhausts:
As a basic rule of thumb there's 3 stages of intake/exhaust: Open, lightproofed and odourproofed + lightproofed. As a minimum you should match an 80mm open fan with a 92mm lightproofed fan or a 120mm odourproofed fan.

I'm rambling now but one other little gem to consider is that you can grow auto's just as well under 12/12 as under any other system. Don't think they have to have 18/20/24 hours light. Combining that with running the lights through the night was a breakthrough for me and provided the basis for everything I've done since.

Thanks v12, some of that stuff I did not know. I do need to know if I can run 5v fans with a 12v adapter. I can not find this anywhere and it is the only thing holding me back from trying the cool tube idea.

-X

Hey Xan

I've never overdriven a 5v fan but I have run 12v fans up to 15v. Personally I wouldn't run yours directly from 12v as they will burn out very quickly. You still have plenty of options though.
The easiest is to just buy a USB hub. The old USB v1.0/1.1 didn't provide power so they came with a 5volt adapter. You can just use that instead of a 12v power supply.

If you need to do it on the cheap then you could wire 2 of those fans together in series and hook them up to 12 volts, which would give them 6v each and should be ok. To do this just hook the black wire of one fan to the yellow of the other. Now connect the remaining yellow to 12v positive and the remaining black to 12v negative.

Another option is to buy a voltage reducer. They come free with some fans like the Noctua range and plug in between the 12v supply and the fan to reduce the line voltage from 12v to about 7v. Here's a link to something available in UK. If you show this to your local pc guy he should be able to get something similar:
http://www.advancetec.co.uk/acatalog/info_08361.html

I use lots of fans so I got something from Maplin/Radioshack that looks like this:
http://www.scan.co.uk/Products/Fractal-Design-PCI-Bracket-Fan-Power-Splitter-Gives-x10-3pin-and-x6-Molex-Connections-from-x1-Input
The fan connectors around the outside provide 12/7/5v when connected to a normal pc molex cable. If it is plugged directly into a 12v power supply like mine is, the outputs change to 4x12v, 4x6v and 4 that don't work but that's fine for me and the 6v sockets should be good for your fans.

How much weight do you expect to pull out of that setup?

Rusty Crutch said:

How much weight do you expect to pull out of that setup?

Click to expand...

Hey Rusty

I think Xander is aiming to run 2 cases so he should be getting decent harvests once he's got the bugs ironed out. I only have a single case and I run it as a perpetual grow with a harvest every 3 or 4 weeks. The last harvest I photgraphed was about 5-6 weeks ago. Here's a pic of the largest of 3 colas:

i dont know if u guys ever look here n e more but i am interested in pc grow box building and i could use some pointers......hopefully someone looks here and finds my request.....