Light Trap (1st Time PC grow)

1st PC Grow

PC is regular size (43X20X44cm) with 3 fans blowing air out and one fan pulling air inside the box.

Given that plants have got to 27days, I thought it was time to sort out a light trap before I can start flowering.

I've started this thread so as to share what I'm doing in case it can help some, and then to get some info from the experienced people on RIU

Pic above is a sketch of a light trap I've made with cardboard.

- The light trap box fits onto the back of the PC box covering all 3 extracting fans (red and orange in pic). I have not included the light trap box for the intake fan, but it's basically the same principle.
- The idea is to break the line thru which light travels into and out of the PC box, while allowing air to travel. The red arrows show the direction of hot air flowing from the fans thru the light trap box and outside.
- How is the line of light broken? By fitting 2 similar cardboards inside the box (A and B), one stuck to the bottom and the other to the top, allowing hot air to move in a 'S' shape until it gets out of the light trap box.
- The numbers are in cm but are not important as everyone's setup will need a differently sized light trap. If you want to follow this to the cm, then here's some more info:
1. light trap box total depth: 20cm
2. distance of 1st cardboard A from the fans: 7cm
3. distance from A to cardboard B: 6cm
4. and obviously dist. from B to the back of the light trap box is 7cm too.
5. Height of cardboards A and B (they're similar): 18cm (with 9cm space above and below them)

Questions:

1. Use a black material for the box, specially a matt one that doesn't reflect much. I used a cardboard from a shoe box and it was smooth and reflected a lot of light. Having done this already, I'm thinking of buying black matt spray paint to paint the inside (and outside why not) of the light trap box.
What do you guys think?

2. For the size of the cardboards A and B and their distance from each other, I would welcome some advice as I believe that it is not only the shininess of the material I used which is the problem but also the distances of A and B etc:

The light trap box is 19cm wide, 27cm high and 20cm deep. The cardboard A and B are 19cm wide and 18cm high, therefore, after being fixed inside the light trap box, leave a gap of 19X9cm. The cardboards A and B are 6cm from each other and 7cm from the 2 extremities of the light trap box (fans on one side and the back closed panel of the light trap box on the other end).

Is there some sort of proportion that I should follow for the distances/size/shape of the light trap?

Any help is greatly appreciated!

Thanks

Uz

Forgot to mention this simple fact:

To make the box, I cut all the sides and the the 2 cardboards A and B. I then assembled everything with black electric tape. You have to be careful in the order you assemble so that it's easier to complete. Best way is to lay all pieces flat in front of you and visualise the box. Then start with one side and work thru all the pieces until there's only 1 last piece of cardboard left to close the box. You can use the tape along the area where one side of the cardboard meets another, by sticking (length-wise) half of the tape to each side that needs to be stuck to each other. Flip cardboard and repeat from the other side.

Used a metal ruler and a cutter (penknife could work too) on a plywood surface to avoid scratching the floor/table when cutting the different sides of the box.

Use a hepa filter made for vacuum cleaners, together with loudspeaker cloth.
This way you can still exhaust the air keep bugs out, and keep light inside your box.

T

Rifman said:

Use a hepa filter made for vacuum cleaners, together with loudspeaker cloth.
This way you can still exhaust the air keep bugs out, and keep light inside your box.

Click to expand...

I cant find these filters (in africa).

Also, where do u place these? Between fans and light trap box or at the exit part of the light trap box, or both?

Doesnt it reduce air flow? Im using pc fans (120mm and 80mm).

I have an old speaker cloth that i could use....

So, just to be clear, my light trap box is not working cos i didnt use any filters with it?
I thought it was the semi reflective material i used plus the size of the gaps inside the box etc...

Spraying the light trap with matt black paint works it doesnt reflect much now.

Theres still a tiny bit of light barely visible, will try adding some sort of black mesh or a elbow shaped outlet at the top.

Might have to add another fan inside to blow some air on the plant as temp rise when i fit the light trap.

I did my light trap for the same reasons. It is from cardboard, black painted and has 100% light absorption.