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drdreww
06-20-2011, 11:12 PM
Can some one explain the use of 2"foam rafts rather than 1"? I didnt have the cash for 2"anf I only bought enough for half of my gb's so if there is a def reason to get 2"i will get that for my next ones.. Using 2"net pots

keith_r
06-21-2011, 05:29 AM
1" should work, paint after drilling - and when drilling, only drill part way through from one side and flip it over to finish, that way your drill bit won't get clogged as often

urbanfarmer
06-21-2011, 07:56 AM
Any size foam will work. The thicker foam will give more support for larger plants. In fact, 2" foam of the same dimensions will support twice the weight in the water as a 1" foam piece. The only other reason I can think of is durability. The 2" in my experience is a lot tougher and not as easy to accidentally snap or break versus the 1" foam. Just be careful with it and don't grow anything too fancy! :lol:


1" should work, paint after drilling - and when drilling, only drill part way through from one side and flip it over to finish, that way your drill bit won't get clogged as often
Paint the foam?? I don't think I would recommend that nor is it necessary!

drdreww
06-21-2011, 08:07 AM
good to know.. thanks for the replies. I was expecting to get some answer about a magical depth for the net pots in the water or o2 levels in the tops of the roots. but the durability makes sense.. ill scrape up my change and get some 2" next time. (maybe) lol

keith_r
06-21-2011, 08:48 AM
Any size foam will work. The thicker foam will give more support for larger plants. In fact, 2" foam of the same dimensions will support twice the weight in the water as a 1" foam piece. The only other reason I can think of is durability. The 2" in my experience is a lot tougher and not as easy to accidentally snap or break versus the 1" foam. Just be careful with it and don't grow anything too fancy! :lol:


1" should work, paint after drilling - and when drilling, only drill part way through from one side and flip it over to finish, that way your drill bit won't get clogged as often
Paint the foam?? I don't think I would recommend that nor is it necessary!

unless you paint it, it will break down, fast
"friendly's" in hi recommends "external latex semi-gloss", but there are probably some other options for this

rfeiller
06-21-2011, 11:09 AM
The 2" allows you to seat the 2" net pot without the bottom of the pot extending below the bottom of the styrofoam and prevents the root crown from being submersed. This is the mistake I was making. Some greens don't mind but a lot of plants do. Use 1" just make the hole smaller so pot sticks up.

urbanfarmer
06-21-2011, 11:29 AM
Any size foam will work. The thicker foam will give more support for larger plants. In fact, 2" foam of the same dimensions will support twice the weight in the water as a 1" foam piece. The only other reason I can think of is durability. The 2" in my experience is a lot tougher and not as easy to accidentally snap or break versus the 1" foam. Just be careful with it and don't grow anything too fancy! :lol:

[quote="keith_r":6v8175ac]1" should work, paint after drilling - and when drilling, only drill part way through from one side and flip it over to finish, that way your drill bit won't get clogged as often
Paint the foam?? I don't think I would recommend that nor is it necessary!

unless you paint it, it will break down, fast
"friendly's" in hi recommends "external latex semi-gloss", but there are probably some other options for this[/quote:6v8175ac]
Oh, I did not know that. You have to be very careful with paint because it can put toxins in the water. Some paints can melt the foam as well.

davidstcldfl
06-21-2011, 01:22 PM
unless you paint it, it will break down, fast
"friendly's" in hi recommends "external latex semi-gloss", but there are probably some other options for this
I know someone who painted 'all of ' the raft with the latex. Even though it was dry, it made the water foam up.....I think they mentioned 'surfactants' in the paint (?) They had to change out all the water twice, to get rid of it
I've been painting the top of the rafts with white rubber mobile home coating. I don't know if it's safer then paint....I was given half of a 5 gal bucket for free.

drdreww
06-21-2011, 06:16 PM
so paint the top side? this system is outdoors too..

rfeiller
06-21-2011, 09:38 PM
what type of time frame, before it breaks down. i've never heard this before and i've never seen styrofoam break down in water, it's used in boat docks, building foundations. amazing. :?

davidstcldfl
06-22-2011, 05:20 AM
.
so paint the top side? this system is outdoors too..
Yes...just the 'top', seems best.


what type of time frame, before it breaks down. i've never heard this before and i've never seen styrofoam break down in water, it's used in boat docks, building foundations. amazing. :?
It's the UV that does it. In a foundation or a boat dock it's protected from the sun.
I have a few extra rafts in a stack (stored outside), the painted tops are doing fine...I noticed the edges are showing a slight break down, after a few months.

I've been trying the expanded white styrofoam....concerned about the fire retardant in the blue stuff....the pink, I've heard, has bug poison in it too. As much stuff we are exposed to, am I being too cautious ?
I've been getting 'virgin foam' made (no fire retardant/bug poison) ...I've tried 1# , 2 # and 3# ( all 2" thick). (FL guys...it's made in Lakeland)
The 1# is too weak and it quickly gets water logged. The 2# is OK, does get 'some what' water logged. The 3# is surprisingly heavy and I think it's stronger then the blue stuff. I think I'll try 2 1/2 # on the next order.

rfeiller
06-22-2011, 07:05 AM
the stuff i use has plastic and mylar films on the outside it is white

davidstcldfl
06-22-2011, 07:51 AM
the stuff i use has plastic and mylar films on the outside it is white
The blue dow board has a film on it too. Rfeiller, do you know what kind/brand name ? Is the mylar wite....maybe it protects the styrofoam ?

keith_r
06-22-2011, 08:31 AM
a clear film i don't think would help with avoiding uv breakdown?
maybe a "milk paint" would work?

rfeiller
06-22-2011, 09:32 AM
White on one side foil on opposite side. I put foil side down to avoid damaging underside of leaves. When you folks settle on a finish let me know. The stuff in my greenhouse shows no damage. This is dense whit nonchem styrofoam. It is a structural foam.

urbanfarmer
06-22-2011, 03:35 PM
White on one side foil on opposite side. I put foil side down to avoid damaging underside of leaves. When you folks settle on a finish let me know. The stuff in my greenhouse shows no damage. This is dense whit nonchem styrofoam. It is a structural foam.
Foil is a GREAT idea! Anything that stops the light will work and foil is definitely safe. The side does not matter. It looks different to the human eye, but there is no significant difference between how much it reflects on either side. According to anything I have read it is equivalent on both sides. Tons of information on this on the net and many folks have even independently run experiments and confirmed the results. The white foam actually reflects more light than the foil. Hope that helps! :mrgreen:

rfeiller
06-22-2011, 03:44 PM
If I have read that also, it depends on the glossyness of the white. One study I read actually said the less glossy the paint the more light that was reflected. I also read another study that said never have reflective foil. Reflecting on the underside of the leaves. I can look at the whit side in the sun but can't look at the foil if that amounts to anything. Thanks for the info.
Rich

urbanfarmer
06-22-2011, 03:49 PM
The diffusion rate is different but the reflectivity is the same. The more polished a surface is the less diffusion of light there is, which is why you can see yourself in something that has been highly polished. This can also be correlated to the "glossiness" of a paint. It gets more complicated from there based on atomic structure and microscopic surface qualities... but anyway, as far as the aluminum foil it all reflects the same amount of light just not all in the same direction because it diffuses differently (that's why you can and cannot look at it in the sun).

Anyway, I guess the only way to find out is to try it! :-D

keith_r
06-22-2011, 04:16 PM
there was some stuff over the last couple years about using the color red around your tomatoes to make them grow "better"..
not quite sure what they've found on that, and don't feel like looking at the moment..

urbanfarmer
06-22-2011, 07:00 PM
there was some stuff over the last couple years about using the color red around your tomatoes to make them grow "better"..
not quite sure what they've found on that, and don't feel like looking at the moment..
I can only guess it has something to do with the light spectrum, but otherwise I have not heard that specifically for tomatoes; so, I have no idea.

davidstcldfl
06-22-2011, 07:09 PM
I can only guess it has something to do with the light spectrum, but otherwise I have not heard that specifically for tomatoes; so, I have no idea.

Even shade cloth is getting into the color spectrum issue....
http://www.signaturesupplyonline.com/#Polysack

rfeiller
06-22-2011, 10:39 PM
it did have to do with the light spectrum, a number of years ago i read of an experiment using reflective color panels for veggie and fruiting stages. lighting was not very refined at the time.

drdreww
06-23-2011, 12:19 AM
So i am confused to what is the best thing to do.. i have 1 whole raft planted, but i can move them to paint if need be?? I'm about to drill my other rafts.. so I want to get this figured out..
I dont know if this will ever be settled

davidstcldfl
06-23-2011, 04:32 AM
drdreww, May I suggest, you drill and paint the foam you have. Once it's dry, transfer your first raft of plants into a 'painted' raft. Then let the first raft dry out, then paint it too.Then you'll be good to go.... :D
On a regular basis, I transfer my lettuces from rafts with the holes close, to ones with the holes further apart, for final grow out. If you have large plants with lots of roots...then it can be more of a challenge.
Plants are pretty tuff....I took some pretty good size 'matter plants out of 4 inch pots, washed the dirt off the roots and 'forced' all the roots into a 2" slit pot.. :roll: They all made it.. :D
Looking forward to some pictures of your rafts full of plants !

keith_r
06-23-2011, 05:20 AM
this was pretty interesting;
http://www.uvm.edu/vtvegandberry/factsh ... rimer.html (http://www.uvm.edu/vtvegandberry/factsheets/plasticprimer.html)

davidstcldfl
06-23-2011, 06:35 AM
Wow, that is interesting...thanks Keith... :D

urbanfarmer
06-23-2011, 11:12 AM
That's a very interesting article. Nice find!

drdreww
06-23-2011, 01:38 PM
My friend at morningstar says that they use the blue dow boards, and the systems have been in place several years, and no problems yet

rfeiller
06-23-2011, 02:32 PM
This is one of those, what was the question :lol:
Good info came out of it.

drdreww
06-23-2011, 05:12 PM
there should be a Raft sticky

keith_r
06-24-2011, 05:35 AM
there should be a Raft sticky
+1