Time to build second grow box, ideas?

This is the third year I've used the same grow box to start my pepper plants, but the first year I've attempted to start more than 10 plants. I'm attempting to start 24 in little bathroom cups, the max I can fit in the box, and so far 15 have sprouted. It's almost time to pot up the bigger guys and the bin is about to run out of room! My project for this weekend is going to be building a second box.
 
I can fit a dozen larger cups in the bin, so my basic instinct is to just replicate the exact same box I'm using now (if it ain't broke, don't fix it, right?), but before I invest the time and money to build this second box I wanted to run the design by the forum and get opinions on what I might improve or get some ideas on how to save money.
 
Here's the current design:
 

 

 
It consists of:
- Five F8T5 light fixtures (http://www.amazon.com/gp/product/B000EEQ58I?psc=1&redirect=true&ref_=oh_aui_search_detailpage) attached to basic frame, height adjustable
- Three 6500K bulbs, two 4100K bulbs, alternating
- Reflective coating on the interior using mercury glass spray paint
 
The lights are on a timer and there's a fan blowing on the whole setup. With the fan on, the soil temperature stays at around 80 degrees F.
 
Here are my thoughts on the matter:
- It's only 40W of light, could be better, but it has proven sufficient for the 2-3 months they spend in the box before going outside
- I can replicate the setup for around $80, but if I can do it cheaper that would be ideal
- Thinking maybe I could save money while increasing wattage by going with CFLs, but it might be more difficult to rig up an adjustable frame for them like the one in my current box
- I want to stick to the same size bin so they can be stacked where they currently are, not a lot of room
- Have to be able to get the parts quickly so I can complete it this weekend
 
Any ideas on how to improve this setup and stay under my $80 budget would be appreciated, thanks!

grow tents are easy prebuilt. easier to store when you're not using them too.
 
a 4x4 one or so would be a large upgrade. then ditch the little lights and get an hps. then you could even grow year round if you want.
120$ tent + 140$ light kit (apollo on amazon for both)
like i say is large upgrade =D but worth it in lumen/$ and convenience 
 
or 
 
cfls are a bit annoying. easier to just get the t8 4' shoplights from homedepot/lowes
then make a box out of expanded styrene 
for 4x2 box need 2 shoplights + 4 bulbs and 2 sheets of expanded styrene.
30$ diy box + 46$ lights
 
or
 
shelf build

juanitos said:

grow tents are easy prebuilt. easier to store when you're not using them too.
 
a 4x4 one or so would be a large upgrade. then ditch the little lights and get an hps. then you could even grow year round if you want.
120$ tent + 140$ light kit (apollo on amazon for both)
like i say is large upgrade =D but worth it in lumen/$ and convenience 
 
or 
 
cfls are a bit annoying. easier to just get the t8 4' shoplights from homedepot/lowes
then make a box out of expanded styrene 
for 4x2 box need 2 shoplights + 4 bulbs and 2 sheets of expanded styrene.
30$ diy box + 46$ lights
 
or
 
shelf build

Click to expand...

 
The grow tent and HPS route is too expensive for me at the moment, I suspect it runs pretty hot and uses a lot of power too. You gotta understand my space restrictions are extremely limiting at the moment. The box currently sits on top of the dryer and that's about the only place for it. Besides, my ultimate goal will be to make shelves like the ones in your link once we get a house with more space, at which point I doubt I would need these boxes or an HPS fixture. At least with my setup I can re-purpose the fixtures as closet or work bench lights. 
 
The T8 fixtures and styrene box idea is nice, I will need to take some measurements to see if I can fit a 4'x2' box in my space, but that could probably fit all 24 big cups and I wouldn't need to run both boxes at once. Thanks for promoting that idea, I originally discounted T8 fixtures as too large, but if I can make it work they would be a good investment and probably be better for the plants.

but really you can just leave them in those cups for another month they are just fine.
 
then you can plan / save up for next year.

You really think they could stand another month in those little cups? Maybe the little guys, but they're growing pretty fast, plus I have some better soil I want to put them in. I feel like they'd do much better if potted up sooner.
 
After giving the T8 idea some thought, I'm not sure it would be better. Right now the space is about 1.5 sq ft, with 40W of light, that's about 27W/sq ft. If I use four 32W T8 bulbs in a 4'x2' space, that's 16W/sq ft. That's less light for the same cost, even though I would gain more space (much of it unneeded), are there other benefits to using a T8 setup in my situation?

If it ain't broke.....for your budget I'd say stick with what you know works.
 
I made a cheap grow box out of cardboard lined with foil once. Very simple and effective. I used 2 of those clamp on shop lights with the 10" reflector
($10 ea. @ home depot), bought a couple screw-in adapters Y adapters so I could run 2 bulbs on each reflector, and used 25Watt cfl's (output 100W of light) giving me a theoretical total of 400watts of usable light.
Worked fine but needed to run a fan constantly because cfl's do get warm.
Used it for a whole year to keep a mother plant going for clones.
Never felt the need to upgrade since it did the job.
 
I'm sure it would work for your needs too

Hawaiianero said:

If it ain't broke.....for your budget I'd say stick with what you know works.
 
I made a cheap grow box out of cardboard lined with foil once. Very simple and effective. I used 2 of those clamp on shop lights with the 10" reflector
($10 ea. @ home depot), bought a couple screw-in adapters Y adapters so I could run 2 bulbs on each reflector, and used 25Watt cfl's (output 100W of light) giving me a theoretical total of 400watts of usable light.
Worked fine but needed to run a fan constantly because cfl's do get warm.
Used it for a whole year to keep a mother plant going for clones.
Never felt the need to upgrade since it did the job.
 
I'm sure it would work for your needs too

Click to expand...

 
If I were to go the CFL route, this is the way I'd probably go. Thanks for posting that. Do you mind posting a link to the clamp on lights you bought? I think I get what you're saying, but want to make sure. Is their position adjustable?
 
I think I'd go with lower wattage bulbs to reduce heating, what size space were you lighting with them?

Just throwing another design into the mix, the budget reflector hood:
 

 
It's raised up higher than it usually is in this first pic.
 
It's basically a suspended metal duct pipe held open by threaded rod with several cheap fixtures wired in.
 
Mine's extra wide and I didn't like how the plants at the edges weren't getting enough light, so I changed it up. I could add more fixtures or use Y adapters for even more light.
 

 
Here's a video that explains it and contains a parts list:
I used the $1.25 basic plastic fixtures instead of the $3+ weather resistant ones. It doesn't look as nice, which doesn't matter to me, but it does leave electrical contacts exposed. You can cover with some electrical tape to be economical, or they have $1 plastic backs, but at that point just go with the rubber lined ones. The bulbs get warm and the ballasts get hot, but there's enough room for them to be air cooled even without the fan. If you were going to cram as many as possible in there then a fan would be a good idea.
 
I also drilled holes through some dowel and put the rods through it. This added rigidity. If you do this get some cheap flat wood instead of dowels. I just used what I had on hand.
 
If you don't like wiring you could get some cheap power strips, secure them with wire ties, and hook up bulbs using some of these:
 
http://www.homedepot.com/p/Leviton-White-Outlet-to-Socket-Light-Plug-R52-00061-00W/100170446

I built a small grow closet out of some cabinet/drawer. One I built 3-4 years ago, and another one a few months ago. I've yet to share it. Inside, I used foil tape, which covers the walls and ceilings of the closet, for reflection. I have one 400 watt equivalent Spiral CFL per closet.

Thanks everyone for the suggestions. I ended up coming in way under budget at around $40 and the plants are happy! 
 
The new design uses two of these lamps with 19W, 5000k, 1300 lumen CFL bulbs. I bought socket splitters for them so I could run 4 bulbs, but the reflective hoods don't give you enough room to do it. It's alright though, there is still more light than the original box and 4 bulbs would have probably been too hot. I was a bit too fixated on wattage before and realize now it's all about lumens, and with this design I get more light using less power  .
 
Other than that they're just rigged up in a bin that's spray painted metallic. 
 

 
Only a month or so before the plants go outside, so this should do until then.