HOW TO: Build a grow tunnel!

A

Agent-Smith

Guest
I'm really hoping this is the last time I have to put this thread up! LOL

For those of you who don't know, this is a project that was started by a man known as Keef Treeez on the original CW. He has disappeared, so I have tried to pick up where he left off. So away we go............
 

Attachments

  • 66542.jpg
    66542.jpg
    91 KB · Views: 3
  • 66543.jpg
    66543.jpg
    113.3 KB · Views: 3
PAGE NUMBER 1



keef treeez
Senior Member

How to build a Grow Tunnel
Hi folks,

After several requests I've decided to take the time to do a step by step tutorial on Grow Tunnel construction.

The tunnels are very easy to build and can be constructed by anyone who can operate a saw and screwgun.

We'll build the tunnel first and then the hydro system.

For those who missed my previous posts, view my gallery to refer to tunnel pics.

The tunnel we'll construct will be a 4'x 8' unit but the basic framework can be adopted to any given finished dimensions.

I'll start with a materials and tool list. This list may expand a little over the course of the tutorial but these are the major items that come to mind immediatly.

For tools:

Circular saw
Screw gun/Drill
Table Saw
Router and table or Dado Kit for table saw
Jigsaw(preferably) or sawzall
2 3/4" and 1" holesaws
Drill bits
1/2" router bit
Paint roller and pan
Bar clamps 12"


Anyone contemplating tool purchase I can recommend the Milwaukee, Ridgid, Makita, DeWalt cordless sets are awesome. For the budget minded the Ryobi are quite adequate but have linited lifetimes. Feel free to pose tool questions.

Materials will follow soon.

-----------------------------------------------------------------------------



keef treeez
Senior Member


Materials
10- 2"x4"x8' Doug fir framing lumber
3- 2"x6"x8' "
2 - 4'x8' sheets OSB
2 - 4'x8' sheets masonite
4'x 24' Mylar Reflective Film
1/2 Gallon Elmer's glue (White or wood is fine)
Drywall Screw assortment 1", 1 1/4", 1 5/8", 2", 2 1/2", 3" 1 lb. each

4'x8' sheet white showerboard
Pond liner 50"x102"
2 Box Fans
Submersible Pump
20' soaker hose
1 1/2" ID Bulkhead fitting
1/2" ID bulkhead fitting
2 - 2"x6"x16' PVC fence rails


------------------------------------------------------------------------------

These links will familiarize yourselves with parabolas as we will be scribing one on the OSB to cut the reflector endcaps to form the parabolic tunnel shape.


http://en.wikipedia.org/wiki/Parabola

http://mathworld.wolfram.com/Parabola.html


This is the trickiest part of the whole layout so a little study here will relieve me of too much translation of the process.

I promise this is all the math you have to swallow except for the rest of the linear measurements.

------------------------------------------------------------------

keef treeez
Senior Member

The grow tunnel is basically two major elements; the reflector and the tray. They are joined and supported by four legs and the tunnel is enclosed by sliding doors on the long sides.

That's all there is to it. Like a salad bar. Serve it up.

Let's start with the reflector. If you've ever built or observed skateboard ramp construction or any curved structure they are all made from a set of ribs or spreaders attached to a fixed endpiece forming the shape of the given structure. The skin of the structure is then fastened to the ribs to form the final shape. We will build a reflector consisting of two endcaps cut to the desired curvature of the underside of the reflector. Five spreaders will be fastened between the endcaps and the reflector sheet will be fastened to that structure to give us the shape of the reflector.

You can take just these reflector instructions to create your own reflector for your garden regardles of size or shape. The idea is to replace the stock reflectors with one giant reflector to enhance and share all of the light with all of the garden. The tunnel completes the unit where the plants are growing inside of the reflector. The reflector being 4'x8' in size. The premise is that the ideal reflector for your garden is one that encompasses and encloses the entire garden. Any less than that and light is escaping and that would be counter productive..

The two endcaps are each 12"x 48" gross area and the reflector curve will be cut from that area. If you look at the curve upside down it resembles a halfpipe. The curve is a parabola where the bulb is located at the focus. This parabola we will draw has a focal length of 12" at the peak of the parabola when it is positioned open side down. The Parabolic curvature is optimum for it's properties of evenly distributing the light from the focal point out to the extremities of the curve or reflector. That extremity is also the perimeter of the garden so what is accomplished is optimizing the light for your perimeter plants. In fact as you will see as we proceed we can actually create better light out at the sides of the tunnel than is available even under the direct bulb.

This enhancement is created by simply flattening off the peak of the reflector(parabolic) curvature. I have chosen to flatten the curve 3" down from the peak. This flat spot serves to reflect the light radiating from the top of the bulb out the the sides where it is more in demand as the light under the bulbs is quite ample.

I'll post some diagrams of this soon when I get some connection security issues ironed out. In the meantime please refer to the gallery and look closely at the construction, you can look at the buds too but let's deal with the setup first.


While your studying parabolas, practice scribing one. Try some various focal lengths. Get a Drywallers square or a framers square(add these to tools list) to help with layout and scribing. You'll want to get the hang of them so when you scribe your reflector you get it right. Notice the dynamics of the various focal lengths. I chose 12" as it allowed the top to be flattened 3" and still leave 8" clearance from the bulb surface.( The bulb is approx. 2" in diameter so the bulb surface is 1" from the focus which is the bulb's element.)

We'll get back to the curve after some feedback and questions.

The reflector sheet is made from one of the sheets of masonite. The other sheet is for the doors(4 doors @ 24"x48") The masonite is laminated with reflective mylar film. This is done by setting up a table with a pair of saw horses and flopping the sheets of OSB on them. Then flop the masonite on them and get out the paint roller and pan and the glue. Thin the glue a LITTLE so it flows in and out of the roller nap easily. Not too thin. I tried spray contact cement and liquid contact cement for this process but the dangers inherent in their use and the fact they don't hold as well eliminates them. Roll out about the first 32" from the end of the masonite sheet. A nice even coat that is not runny is best. Have a friend hep you position the mylar square to the end and gently lay it out on the glue. then pull it up to get it tacky for about 10 or 15 seconds and the lay it down and squeeze out any air bubbles. If you have ever done vinyl stickers on glass or shelf papering use a similar technique. After getting that area done proceed to the next 32" run and repeat and again to finish the sheet. I do it in sections because trying to do the whole sheet at once can be a disaster.

After laminating both sheets of masonite stack them between the osb and put it on the floor flat and put some weight on it overnite.

--------------------------------------------------------------------

keef treeez

Getting Started
Here is a pic of the end template for the reflector. The curve is cut from a 12"x48" piece of 1/2" OSB. My new larger tunnels use a piece 16"x60". I'll run through the scribing process if enough are interested and really are going to build. As suggested above, see the parabola links for curvature background.

Posting pics seem to be an excessive one at a time chore. Any tips. I have alot to post.

-------------------------------------------------------------------------------------------
 
PAGE NUMBER 2


Posted by keef treeez

Gro Tunnel Intro

To Begin, Why would any one want to build such a thing as a Gro Tunnel?

The tunnel design was, and continues to be, an evolution of solutions to all the issues related to producing on a level any larger than closet level.

Other issues addressed are the excessive retrofitting in any given house. I wanted to design something that allowed a setup to be done quickly without attaching anything to ceilings and walls.

My ballast assemblies pictured above subscribe to the same design ethic. They wheel in and plug in to the Timer and to the individual Socket cords.


The motivation to build a better gro containment system originally began as a way to make the use of CO2 more practical by reducing its use to a minimal gro space instead of flooding a whole room. To Date, I have yet to employ the use of CO2, instead continuing to focus on lighting and workflow efficiency. CO2 will come later after I am satisfied with the primary issues. As it is, The record personal yields give me little reason to dive into CO2 yet with the additional issues it will introduce.


It became evident that lighting efficiency could also be greatly enhanced by trashing the individual reflector concept and mounting the bulbs inside of one large reflector.

That reflectors' shape was easiest and most efficient to build in a tunnel form as opposed to square. The tunnel shape allows the whole length of the tunnel to share in all of the light. The tunnel shape also allows efficient airflow. Tunnel configurations have been constructed as long as 40' using no cooling and have experienced no overheating problem.

For those that missed my original posts I'll post some of the first large setups. Those are 4' width tunnels and are lit by 3x400w for each 8' length.

Oh yes, I almost forgot the best reason to build a gro tunnel. They have more than doubled yield per watt and the accompanying hydro system uses little or no media. All of the materials are available everywhere.


--------------------------------------------------------------------------------
Posted by keef treeez

Build the Reflector

Here are the parts for the reflector skeleton layed out for assembly.

This is a detail of the upper door guide profile. Two are cut from a single 2'x4' with the table saw set at 30degrees. The groove can be cut on a table router or a table saw with a dado bladeset.


--------------------------------------------------------------------------------
Posted by keef treeez

This stage of construction can benefit any garden whether you plan on a tunnel or not. Anyone can improve their lighting efficiency by building this large reflector. The dimensions are purely relative to the size of garden you intend to light.

First attach the end templates to the ends of the ridge piece(2x4). The underside surface(now facing up) of the ridgepiece should be flush with the cut on the template.


--------------------------------------------------------------------------------
Posted by keef treeez

Next add the rest of the ribs.


--------------------------------------------------------------------------------
Posted by keef treeez

Finally attach the reflector skin. It is attached with 1" drywall screws. I don't have pics of the process of attaching the mylar to the masonite board but it is very easy. White glue spread thin with a paint roller and roll out the mylar. Let dry 24 hours.


--------------------------------------------------------------------------------
Posted by keef treeez

Be sure to center the reflector piece by marking center points on the template and skin. The 5'x 8' reflector required 2 skin pieces. The 4' wide one can be done with one sheet of 4'x8'


--------------------------------------------------------------------------------

Posted by keef treeez

Time to stand up the reflector. The door guides were located 1.5" from the sides of the template to accomodate the narrow side of the legs. Assemble one end first and than the other.


--------------------------------------------------------------------------------
Posted by keef treeez

Almost forgot to show the latest starts. Healthier than ever. Got to get this tunnel built for them.


----------------------------------------------------------------------------
Posted by keef treeez

Next clamp blocks 30" from floor to rest the tray for attachment.


--------------------------------------------------------------------------------
Posted by keef treeez

Here is the basic tray, there will some added underside support after attaching to structure.


--------------------------------------------------------------------------------
Posted by keef treeez

Rest the tray on the first blocks then crawl inside and tip the tray in and slide to the other end and rest on blocks.


--------------------------------------------------------------------------------
 
PAGE NUMBER 3

--------------------------------------------------------------------------------
Posted by keef treeez

Attach Tray. Pilot drill the screw holes through the leg with 1/8' bit. Note that pilot hole was angled up towards tray giving stornger hold.


--------------------------------------------------------------------------------
Posted by gudsm

What do you seal the tray with?

--------------------------------------------------------------------------------
Posted by keef treeez

quote:


--------------------------------------------------------------------------------
Originally posted by gudsm
What do you seal the tray with?
--------------------------------------------------------------------------------


Hi Friend, You can use any suitable liner material. Some use even common 6 mil poly. Pond liner is good. Whatever will not leak and is cheap enough to call disposable. I'll get the name of the exact material I'll use soon.


--------------------------------------------------------------------------------
Posted by keef treeez

The legs need bracing, Start with the inside lengthwise bracing.


--------------------------------------------------------------------------------
Posted by keef treeez

After attaching to the leg add a block that is both attached throuth the bottom of the tray and the outside face of the brace.


--------------------------------------------------------------------------------
Posted by keef treeez

Finish the corner with the end brace.


--------------------------------------------------------------------------------
Posted by keef treeez

Add the undertray support


--------------------------------------------------------------------------------
Posted by

Along the way be checking for plumb and level.


--------------------------------------------------------------------------------
Posted by keef treeez

Ready for the Liner


--------------------------------------------------------------------------------
Posted by keef treeez

The underside joists need hangers for additional support. You can use plumbers tape or steel strap, soup cans, license plates. whatever


--------------------------------------------------------------------------------

Posted by gudsm

Wow that looks great. I am making a parts list and am the way to the store. How long did it take you to get this far along? I have all the tools so hopefully I can get on this in the morning.
--------------------------------------------------------------------------------
Posted by keef treeez

quote:


--------------------------------------------------------------------------------
Originally posted by gudsm
Wow that looks great. I am making a parts list and am the way to the store. How long did it take you to get this far along? I have all the tools so hopefully I can get on this in the morning.
--------------------------------------------------------------------------------



Right on, I'll be glad to keep you on track. Most of these pieces were precut for today's assembly so it only takes total about 3 or 4 hours depending on seshjuan breaks. With cutting and measurements add another couple hours. Uploading these pics is almost more time consuming.


--------------------------------------------------------------------------------
Posted by keef treeez

Liner Installation...


--------------------------------------------------------------------------------
Posted by keef treeez

Drain and inlet hardware. The white pieces are scrap showerboard drilled for the drain and inlets. Those pieces act as a backer for the drain and inlet flanges. The thin rigid material is better than flanging to the OSB board. See the under side shots where the flange backer is centered in a larger hole cut through the tray bottom.


-------------------------------------------------------------------------------
 

Attachments

  • 19809.jpg
    19809.jpg
    149.1 KB · Views: 4
PAGE NUMBER 4


keef treeez
Senior Member

The next thing is to setup the field. This was the most challenging solution yet was so simple in the end. How to free suspend the field sturdily over a wide tray of shallow water. You'll need the 2 2x6x16' PVC fence rails. Cut a length 92" to fit comfortably within the inside lengthwise measurement of the tray. Now rip it lengthwise in half about 2 3/4"minus blade width. These are the side support rails that a series of cross members will be resting upon.

------------------------------------------------------------------------------------

keef treeez
Senior Member

The rip dimension of the side riser rails could be less than the 2 3'4" split of the full piece. I may lower that rise to accomodate my recent switch to 2" netcups that are shallower than the 3" previously employed.

The next step is to drill out the Topsheet. The cup spacing could depend on whatever you are comfortable with and of course how many starts you may have.

Have at hand a good dust mask, a shop vac, and a table with a sheet of scrap OSB to drill onto. I cut the shower board into four pieces per 8' tunnel. It can then be drilled in one fourth of the time stacking up the four pieces. This also makes cleanup and any other handling much easier with a smaller sheet.

Most of these pics are of a 5' width tunnel If you are building a 4' adjust dimensions accordingly. I'll get into the finer dimensions as the questions arise.

Note The 5' and 4' width dimension is the Footprint dimension. All cuts inside of that gross outside dimension must accomodate any material dimensions.

-------------------------------------------------------------------------------------------

keef treeez
Senior Member

--------------------------------------------------------------------------------
Originally posted by suzy cremecheese
A few questions.

What is your average yield per watt?

How many plants per sq ft do you use?

How much time do you spend pruning?

How much do you estimate a unit like this costs?

Thanks
s


PS

for the 'black spot' show some pics and I'll see what I can dig up. I can't promise anything but I will look.

Pics using various lenses to show the mycelia would be exceptionally helpful in diagnoses as well.
--------------------------------------------------------------------------------


The yield in my last healthy cycles was about 1.25-1.5gpw. The best group was just shy of 4lb in 30sq. ft using 1200 watts=1.5gpw. Better can definitely be achieved.

The spacing in those older shots was 96 individuals in the 4'x8' tunnel. Inside dimension is 42"x93" making spacing 7" across and 5.75" lengthwise.

Those plants were subjected to very intensive training and defoliation. My old thread on the Bombsai method is around somewhere. There is another lively one on Trimming Fan Leaves. Although I have practiced this method probably more than anyone and promote it I am not totally sworn to it. I plan to do a group with no bending and deleafing now that the tunnel design has firmly proven it's efficiency. My objective has been to challenge the typical way of production using excessive wattage and oversized, unwieldy plants in hopes of increasing yields though ordered uniform production techniques. There has been a very small reduction in TOP bud size in exchange for prodigious production elsewhere.

Don't have any pics of the Blackspot. Thankfully it's gone for now. I'm sure any expert could add little beyond encouraging switching up fungicides to reduce resistance. It would just be nice to hear an expert expound on findings actually gleaned from studying Cannabis diseases.

Almost forgot the cost... About $400 depending on what you may already have at hand. What you save on wattage and make on increased production will pay for all of it and more.

-------------------------------------------------------------------------------------

GrowGreen
SOGerator

Nice thread keef.. Good to see you back.

Can you substitute sheet metal instead of the mylar? Are you using mylar because of its cost?

Peace
GG

---------------------------------------------------------------------------------------------

keef treeez
Senior Member


Thanks GG,

Sheet metal was an option but cost and availability eliminated it. Architechtural Super 8 grade is over $2000 per sheet. Arch 8 is $200 as is Polycarbonate mirror. Masonite is $12.00 and the mylar is about $10.00($1.00 if you use wallmart emergency thermal blanket mylar) Thin mylar is fine as it will be sturdibacked by the masonite.

Cutting the mylarboard is way easier than metal too.(No cut fingers) The simple application of mylar to masonite suddenly makes a light strong structural panel material perfect for our uses. Amazing no one has a product like this on the market.

I was initially leaning toward using sheet metal because of the heat exposure issue to the lamps but 400 and 600 watt lamps within 9" has not shown any heatup on the panel close to the lamps. I first used a small metal heat shield couple of years ago to ease my mind but it was unnecessary. The mylar is enough of a heat reflector and the smooth flow of air in the tunnel prevents any risk of fire from heatup or scorching.

-------------------------------------------------------------------------------------------

GrowGreen
SOGerator


Any tips on keeping the wrinkles out of the mylar...thats my biggest problem with it..

-----------------------------------------------------------------------------------------

keef treeez
Senior Member

I was fussing with the wrinkling till i realized it only made for nice deflective surfaces.

Thinning the white glue a very little allows it to flow in and out of the roller pad easier and also provides some "float" to use in adjusting the film after laying on the masonite. I do the sheet of masonite in 2' sections to not get ahead of myself and prevent bubbles. Some finesse and long reach and a sweeping motion over the mylar as it is lain. I sweep in a long arc at 45 deg. to the square of the sheet to achieve my best results. A dry knit t shirt slides nicely over the mylar if your hands don't. Dont rub it too much. The mylar dulls with each sweep.

-------------------------------------------------------------------------------------

keef treeez
Senior Member

Welcome Cabbageman,

I was using the aerosol at first but the overspray mist is so toxic and the results were actually not as good as the white or yellow carpenters glue to my surprise. The aerosol contact cement applied peeled in a few months where the elmer's apllied is still solit after more than 2 years. I tried liquid contact cement both regular and water based abnd stil l not as strong adherence and more expensive and of course so toxic. The reguler solvent based is a fire hazard if used near a pilot.

----------------------------------------------------------------------------------

GrowGreen
SOGerator

I used the 3m product, cabbage. Mylar and I, just don’t get along. I may try some of that Duraflect stuff. Its tough, waterproof, flame and tear resistant.. I have a bunch of thin stainless laying around, I may try that for the reflector, and duraflect for the sides.. What do think about that keef ?

---------------------------------------------------------------------------------

keef treeez
Senior Member


--------------------------------------------------------------------------------
Originally posted by GrowGreen
I used the 3m product, cabbage. Mylar and I, just don’t get along. I may try some of that Duraflect stuff. Its tough, waterproof, flame and tear resistant.. I have a bunch of thin stainless laying around, I may try that for the reflector, and duraflect for the sides.. What do think about that keef ?

--------------------------------------------------------------------------------

I think it was the 3m spray contact cement that made it difficult. You have no float time with it to smooth wrinkles and remove bubbles. Try the white glue, believe me it's the best way. Rolls on easily with a paint roller. After the job toss out the roller. No fumes no toxic mess. It's all in the setup. Actually a breeze once you get your technique down. Not sure what is duraflect but if you have it around thats fine. The mylar/masonite board functions best also as a structural complement to the ribs that piecing in metal will not suffice. I urge you to try the glue with mylar again as I have been well around this material selection routine for the last 3 years and I have reached these conclusions based on the widest possible set of functions, price, ease of handling. Not trying to press my way of course but I can certainly say that after building and rebuilding these things maybe 50 times these materials represent the lowest tech way around. One easy option is enameled white masonite or shower board. It's glossy white. I still prefer the mylar board.

Here is one variation on materials I'm playing with but I think the rigid board has advantages. Here mason's line replaces the wood ribs and foylon would be draped over it. Nice and lightweight but not as tight in the breeze of the fans and in case of using CO2. The foylon of course could be stapled on the underside of the wood ribs. I thought of the twine solution as a nice way to set up a very large setup with least materials and time of setup.

I hope i didn't discourage your experimentation, only applying the parameters I've been using in design and construction so far.
 
PAGE NUMBER 5

keef treeez
Senior Member

After the Liner is in, the next thing is the aeration coil which is just my fancy name for 4 8' lengths of soaker hose. They are hotglued to the bottom of the liner. I'm not sure you can do this to polyethylene. This liner material I use is about 12 mil and extremely tough. I had to order out of Texas in large bulk. I'll get the link for it as soon as I can dredge it up.

------------------------------------------------------------------------------------------

keef treeez
Senior Member

You can also sink the coil in the water using weights.

---------------------------------------------------------------------------------------

keef treeez
Senior Member

Here's a better shot of the Soaker hose Array.

Also pictured is the socket assembly. This is the fun part, you can now sell your old reflectors to the next guy while you upgrade. In a couple of months you can help him build his tunnel and be giving the same advice. He'll be stoked as will each guy down the line. Maybe even the local hydro shop will take em off your hands. Mine went to the local metal recycler.

If you sell your barely used complete light setups you can probably by 2 or 3 bare bone sets for that one and I'll go over my Mobile ballast cart assembly here soon.

Nothing like saving money while setting up to make more.

--------------------------------------------------------------------------------------------------

keef treeez
Senior Member


The bracket for the socket is a 12" simpson tie bent L shaped. These are the cheapest metal bracket I could find. Under a dollar a piece I believe.

Note the cord is just a section of extension cord with the male end intact. Again cheapo is the best way. These are quality cords acquired at one of those blowouts for 5 bucks for a 50' cord. The female end is wired into the lamp side of the ballast. No need for fancy sockets. They all provide the same conductivity. This is for 400 and 600watt lamps although i have safely run 1000wat lamps on the same cord. The cord on todays HiTech ballasts is super overkill being heat and oil and grease resistant and thick as a bull's dick. Same guage copper inside. Infact my cords are 12guage and most sets I see use 14 or 16 guage in the same application... That's thinner wire for the AWG challenged.

I recommend against buying most factory ballasts. I have seen much substandard wiring and mounting inside those shiny cases. I'll wire my own, thank you. I won't risk my freedom and safety on some ballast wired by a high-school kid at min. wage. You can bet most builders hire whoever to join the assembly line with no clue to what they are building.

---------------------------------------------------------------------------------------------

keef treeez
Senior Member

Rambling is welcome...

I'm not that familiar with the ignitor switch hack but I also use hps only for flower. Veg will be in their own seperate tunnel with 250HPS and 400MH combined. I can see clearly, though, in this veg arrangement that the individuals closest to the 250 HPS are beefier, stouter, deeply furled, branchier, I could go on. I had the 400 MH ballast stored for a couple of years so in a pinch for a lower wattage light I bought a agrosun bulb for it. I wish I'd saved my money. Again, for the third time in 25 or 30 years I have proven, at least to myself , That hps is all that's ever needed in veg. MH is totally lacking, I think 160 watts of flouros are nearly as good. I hope I don't trigger the old MH opposed to HPS VegDebate, this is just my observation reinforced several times over.

--------------------------------------------------------------------------------------------
ceteris paribus
truth addict

holy cow, very informative pic tutorial! i'm glad you showed back up when you did, as i'm just about to build a new ebb&flo table. your carpentry skills make my stuff look like it's built out of lincoln logs, lol.

-------------------------------------------------------------------------------------------------

keef treeez
Senior Member

Thanks CP, Hope all's well on your end.


Long day yesterday. Thanks to all who are following. I blazed through some of the details like dimensions but I can go over any of it when the question arises.

More to get done before it's rest time though. Those starts are hounding me for more legroom.

I have to drill out the field sheets. First thing is to layout the centerlines so I know where to drill.

I'll get my drywall square, Power Drill with 2" holesaw and shopvac. I'll post a pic as soon as I get setup.

--------------------------------------------------------------------------------------

gudsm
Senior Member

This is a very helpful thread for me. I have started this prodject this morning and will be posting as I go. I have to clean out the trailor today and build my walls and then I am going to build one like yours but longer 4' x 16' with 6 400s.. Thanks

--------------------------------------------------------------------------------------------------


suzy cremecheese
Senior Member

KT,

I have an idea that might or might not help... It might also cause problems with height restrictions.

What if you extended the sides of your parabola straight down a little and installed a piece of glass at the bottom. You could get your tops closer to the light and air cool your bulbs. It would be ideal if the top section of this tunnel was height adjustable. If you did it in sections of glas it would be cheaper and easier to clean.


Ive attached a sketch. If i'm not being clear let me know and please tell me why this would or would not be an improvement. Thanks

---------------------------------------------------------------------------------------------------

keef treeez
Senior Member

Thanks Suzy, That one's a natural and has been considered. Anyone willing to extend this project to that is welcome. As it is , heat is not a problem in these tunnels. At least in my region and it does get plenty warm here. The tunnel shape allows free flow of air from one end to another employing a single $10.00 box fan at each end running on low(10-15 watt draw). This low tech kind of solution is what this design is all about. That's why the cooling aspect with the additional glass(heavy,expensive), woodwork(considerably more complex than present design) and fans with ducting(more setup, expense, wattage draw) are actually something I am trying to do without. I use only 400 watt lamps as they are more than adequate despite what many believe. It's the tunnel design that gives the 400 the power to produce as well as any lamp.

-------------------------------------------------------------------------------------------

keef treeez
Senior Member

quote:

--------------------------------------------------------------------------------
Originally posted by gudsm
This is a very helpful thread for me. I have started this prodject this morning and will be posting as I go. I have to clean out the trailor today and build my walls and then I am going to build one like yours but longer 4' x 16' with 6 400s.. Thanks again
--------------------------------------------------------------------------------

Sounds ambitious. Very cool. Do you have room for a 5' footprint width?

-----------------------------------------------------------------------------------

keef treeez
Senior Member

Here is the layout for my topsheets. Your spacing may vary but these are spaced 6.75". There are 4 sheets stacked ready to drill.

------------------------------------------------------------------------------
 
PAGE NUMBER 6

keef treeez
Senior Member

Time to get to drilling, put on the dustmask, this is the messiest part of the job.

---------------------------------------------------------------------------------------

gudsm
Senior Member

I only have 40 inches to spare with a 4' section. That is 20" on each side. I am building this in my trailor that is 94" wide 10' tall and 40' long. So 5 ' wide would only give me 14" on each side. I am not that little so I will use the 4' modle and have 20" on each side.

What were your results using 1000 watters? I know you said 400 are great but I am just asking... How hot does it get normally around your grow tunnel?

---------------------------------------------------------------------------------------

keef treeez
Senior Member

quote:

------------------------------------------------------------------------------
Originally posted by gudsm
I only have 40 inches to spare with a 4' section. That is 20" on each side. I am building this in my trailor that is 94" wide 10' tall and 40' long. So 5 ' wide would only give me 14" on each side. I am not that little so I will use the 4' modle and have 20" on each side.

What were your results using 1000 watters? I know you said 400 are great but I am just asking... How hot does it get normally around your grow tunnel?
--------------------------------------------------------------------------------


The 4' sound suited for that. You'll make best use of the materials building that size anyway. That's why I started with the 4' width.

Have never used 1000w in this current design. Last trial with 1000w used a single one on a lightrail in a crude tunnel. They are very hot in a tunnel or not. I wouldn't use them i the tunnel without a mover. . It produced no better results. Looking at inversely, I could say, as I have before, that the 400w produces comparable results. Considering we are talking about a 60% reduction in power draw and a similar reduction in heat to deal with I see no reason to continue to use them. I was so eager to be rid of mine. Designing the tunnel was a part of that initiative. Haven't seen a 1000w around here for over 3 years. My yields have continued to rise with each reduction in wattage. Sounds pretty crazy but it's true. I'm glad you are building one because you will soon see first hand just how incredibly bright the interior of this unit is making it clear how over powered a 1000w is for this highly reflective environment.

The small investment in bare bones 400w(under 100.00 w/bulb each) makes the conversion relatively painless and starts racking up savings with each lit hour.

--------------------------------------------------------------------------------------

keef treeez
Senior Member

While drilling you want to wear a good mask, and position the nozzle of the shopvac close as possible to the holesaw. I use anything soft and heavy like this toolbag to hold the nozzle in place. The stack of showerboard sheets is held tight by a a 2x4 clamping them to the undersheet of OSB.

---------------------------------------------------------------------------------------

keef treeez
Senior Member

Finished. Fortunately these sheets will last forever. If I could just settle on a satisfactory spacing I would not have to drill these things anymore.

---------------------------------------------------------------------------------------

keef treeez
Senior Member

Airlines installed and routed, time for some solution and place the girls

---------------------------------------------------------------------------------------

Yimmy
Senior Member

Lookin good KT.

Are you sportin 78 openings this go round instead of the usual 96?

Will the entire field be the same strain?

Thanks for the cool How To....so simple and easy.

Yimmy

---------------------------------------------------------------------------------------

keef treeez
Senior Member

Jo Yimster, The rocks only provide the necessary fiber if they're Asbestosi. Tumbled Granite and feldspar ain't got the roughage. Too smooth.

This 5x8 unit has 112 spaces. 8x14. Have a mixed group this go round. By the time I get to filling the 3rd or 4th unit I should get a full field of Bluberries.

Crazy scene, Subi overheated on the last transport run with carloada girls. Leonus busy with bank robbers. Coolheadz prevail and the air bubble burped out the top hose. Runnin' cool as coolrunnins. Slid into homebase untouched.

---------------------------------------------------------------------------------------

Yimmy
Senior Member

WOW!

112 spaces, so.....

If the whole field was BB,

1- would it be single colas/quick veg,maybe 5 days or less.
2 - week veg with trim and twist method?
Is the tunnel sportin 2 or 3 400w's?

When ya get setteled from the subi ride (good thing it was just a subi FART) and the tunnel is loaded give us a pic update maybe showin the girls movin into their new home.

How old are these girls anyway....LOL LOL
did the bank robber get away clean?

L8r

--------------------------------------------------------------------------------------
 
PAGE NUMBER 7

keef treeez
Senior Member

Yim, This group will be hacked up as mothers and bent and twisted most likely. Next groups will be allowed to be solo shoots, leaves on.

Had to wrestle with a recurring problem that was so simple. Recently many individuals that had been transferred from veg damped off terribly and died. After converting to 2" cups and installing extensive aeration in the shallow bath the cubelet had become saturated from aeration spray and drowned the transition zone. Glad I got to the bottom of that. I think I'll just aerate the tank instead of the bath.

------------------------------------------------------------------------------------------

keef treeez
Senior Member

This will be the CloneVegTunnel. Notice it's on casters for easy mobility. This room is in setup stage so rearrangement is always possible. I'll build a double deck CloneVeg unit soon to accomodate more capacity. I'm in no hurry to bud right now while the numbers grow.

----------------------------------------------------------------------------------------

Yimmy
Senior Member

SLick pics for sure....nice detail....What kind of 90deg. fitting is that...did you glue/seal it into place?

------------------------------------------------------------------------------------

keef treeez
Senior Member

Nice job GUDSM

You whipped that together in no time.

Just order ballasts, sockets, bulbs. The sockets will be mounted to a simpson 12" tie(part#ST12) You'll need to drill the strap for the correct hole spread on the back of the socket. Find some 50' AWG14 extension cord to wire to them and the ballasts. Judge the cords by the receptacles. Are they plastic-like or nice and tough. How is the fit plug to receptacle, secure or loose. I like the Electricord brand with the nice rubbery sheath. Have some Zip ties to secure everything.

Is that a parabolic curve? If so what focal length? I only briefly mentioned the little detail about flattening the top of the curve to spread the light from the top of the bulb out to the sides. That will function fine I'm sure. You'll be able to fine tune the beam by adjusting the distance from socket to reflector surface. I use about 9" now.

---------------------------------------------------------------------------------------------

smokindogcujo
Member

quote:

--------------------------------------------------------------------------------
Originally posted by keef treeez
... I only briefly mentioned the little detail about flattening the top of the curve to spread the light from the top of the bulb out to the sides. That will function fine I'm sure. You'll be able to fine tune the beam by adjusting the distance from socket to reflector surface. I use about 9" now...
--------------------------------------------------------------------------------


keef treeez,
Would you mind going into a little more depth on how you scribed the parabolic curves?

--------------------------------------------------------------------------------------------

keef treeez
Senior Member

quote:

--------------------------------------------------------------------------------
Originally posted by smokindogcujo
keef treeez,
Would you mind going into a little more depth on how you scribed the parabolic curves?
--------------------------------------------------------------------------------


I'll draw the whole thing out tomorrow morning and post it. I need to draw it on white plastic so it will show up in a photo. Tried to show it on wood but couldn't make out the pics.

--------------------------------------------------------------------------------------------

keef treeez
Senior Member

Tunnel racing
quote:

--------------------------------------------------------------------------------
Originally posted by Yimmy
....What kind of 90deg. fitting is that...did you glue/seal it into place?

--------------------------------------------------------------------------------


That's a 1/2"ID bulkhead sealed with plumber's putty against the liner and flange backer. The elbow fitting is a 1/2"NPT x 3/8 barb made by TORO. I had a bunch of them sitting in an old box of plumbing gear. It restricts the inflow enough to produce a jetting action stirring up the bath on inflow. It's threaded in with teflon tape.

---------------------------------------------------------------------------------------------

keef treeez
Senior Member

Parabolic Enscriptions
Let's start by reviewing the principles of a parabola. I'll play professor of planar geometry.

The parabola can be described as a curve plotted from points which are equidistant from a point(focus) and a straight line(directrix).

Sounds simple enough. Much easier to picture and understand after we plot a few points.

These links give a much more technical exploration of the parabola. It can get very deep.

http://en.wikipedia.org/wiki/Parabola

http://mathworld.wolfram.com/Parabola.html

---------------------------------------------------------------------------------------------

keef treeez
Senior Member

I'll scribe it on a sheet of shower board 48" wide 30" tall. If you are making a template to use as a cutting or scribing guide, masonite is a good material for that use.

First scribe a centerline vertically.

-------------------------------------------------------------------------------------

keef treeez
Senior Member

I'll scribe it on a sheet of shower board 48" wide 30" tall. If you are making a template to use as a cutting or scribing guide, masonite is a good material for that use.

First scribe a centerline vertically. Then locate the Vertex 12" from the bottom and the focus 12" above that on the centerline. The Directrix is the bottom of the sheet

--------------------------------------------------------------------------------------

keef treeez
Senior Member

Mark some little hashmarks at 1" intervals between the vertex and the focus. Scribe lightly guidelines horizontally through the hashmarks.
 
PAGE NUMBER 10

keef treeez
Senior Member

here is a mini tunnel I threw together from scraps to house the rescued plants in the perlite mix. I'll keep these around long enough to milk them for a thousand clones. This little tunnel stands on shorter legs and the plants can sit right on the floor. It's only 64" long and 32" tall. The single 250hps in there is adequate to get the growth i need.

-----------------------------------------------------------------------------------------

GlassMan
Senior Member

Hey Keef,
This is a great thread. I'm in need of a good reflector for 3 or 4 400w lights, looks like I found the right thread. I have room to stretch the width to 5' and the lenght to 10' , maybe even 12'. Do you think 4 lights would cover 5x12 ? I hate to hear that you like HPS so much over MH, cause I've got a bunch of 400w MH's. I guess I'll switch them out as I have the cash.
I know you went to a bit of trouble posting the parabola info, but am not sure how important the precise shape actually is? You seemed to say, in one response, that you didn't really think a specific curvature was a big issue? Or did I get that wrong? If I'm incorrect, how did you choose the particular parabola that you used, and how would the 5' wide differ?
Also, I'm wondering if your light height is adjustable? What size are your plants when you begin flowering, and what height are they at harvest?

-------------------------------------------------------------------------------------

keef treeez
Senior Member

Greetings GM,

I'm running 4 x 400w hps right now in a 5' x 8' unit. I think that wattage it could be stretched to 12' but if you can get 1 or 2 more it will be worth it.

I like the 5' width much better than the 4' and I may build to 6' soon. The tunnel is so efficient that 400 wats lamps have no problem spreading out to the fringe on the 5' wide unit. The 4' was what I started with to make best use of the materials. There is little waste in the wider units now that I've built more than one.

I arrived at the focal point by estimating the depth of the reflector I wanted and matched it to the width of the box. Since this thread was posted I've built a little deeper reflector so that the focal adjustments have a wider affect.

The precise shape is not that important but worth the trouble to scribe. It's very easy. Having an idea of the curves dynamics will help in fine tuning later. Anyway the reflector sheet is hardly digitally accurate when mounted, it's only an approximated parabola.

Fine tuning the reflector is on my long list of projects. Right now it performs so fantastically I am satisfied for the moment. It certainly is open to your own interpretation. I arrived at the current focal length by convenience and knowing the reflector would likely be about 12-16" deep.

I hope you take the time to build one of these units. They are fun and easy to build. No one has yet to get motivated enough to build one yet complete, but this thing is designed as a complete system that simply kicks ass on every other system and method. I've only been running it for 2 years now and continuing R&D but already is far and away superior to any way I have used in 30 years. This system is the culmination of that experience with just about any method you can think of and more.

I am about ready to build a 6'x12' unit. It'll be a beast but may be the most efficient configuration for 600watt lamps which I may prefer for their inherent efficiency.

-------------------------------------------------------------------------------------

GlassMan
Senior Member

Keef,
I've been thinking about your grow tunnel all day and it has me excited about making one too. My growroom is 9.5' x 16' and I'd sort of thought about making a large tunnel like the 6x12 that you are planning, but after a bit more thought and some sketching I've come to the conclusion that I'd be better off making 2 smaller tunnels. I'm thinking two 5x8 tunnels would probably utilize the space better and also give me the advantage of running two identically sized units. That will give me the opportunity to have staggered crops, make various comparison grows (nutes, strains, pruning, lighting, etc), and also allow me to turn one off if un-needed. I'll have a total of 80 sq ft which will be plenty of growing area for me, especially if I can learn to get the yields you get.
I'll build one first to get the bugs worked out. I've tried DWC with some success but got tired of dealing with pH swings and the noisy air pump and switched over to an organic soiless mix. I'll just keep using the soiless mix for the first tunnel, then with the second tunnel I also build the hydro unit that you are using. Is your system considered, DWC or NFT ? How much of your high yields would you guess are attributed to using hydroponics?

I've got a busy summer planned so will just do the first reflector asap. Then have to shut down for all of August for a trip out west, Yellowstone etc. (go for the spirit, bad for the growing ). Then I'll return and begin cloning and/or germinating and construct the second grow tunnel. I'm sure I'll be pestering you with plenty of questions then!

Thanks for giving me such a well thought out game plan.

------------------------------------------------------------------------------------

keef treeez
Senior Member

Good plan GM,

I split each 5'x8' tunnel into 2 trays(fields). It's easy to stagger groups that way. You have the right idea. So your two tunnels can eventually have four staggered groups. If the room is just 16' long build one 8' tunnel first and the second tunnel can be scaled down lengthwise enough so you can get around.

My hydrosys could be considered SWC(shallow water culture) or NFT. All I know is it just works. When engineering it I wanted to have a shared bath in a field instead of gutters, tubes, pipes, etc. All of those systems suffer from excess plumbing and hardware. Having built and dealt with many copies of popular systems this one eliminates all the hangups associated with those setups. No media, plumbing, proprietary hardware.

I do attribute the yields to the open-field-hydrosys as it eliminates most of the variables(media, inconsistent moisture delivery, erratic ph) associated with other systems and methods and allows unrestricted root reach

I forgot to add that one of the imperatives in the design was to eliminate fungus gnat habitat. It does. Haven't seen a gnat since the design switch.

Good luck and feel free to fire off any query. KT

----------------------------------------------------------------------------------

GlassMan
Senior Member

Hey Keef,
One more question, is the reflector's height adjustable? What is the height between table top and the reflector's bottom, 48" , 36", ?". Uh, guess that was two questions......

--------------------------------------------------------------------------------------

keef treeez
Senior Member

The Reflector is adjustable but basically fixed. In the construction you can set any height you want dictated by your door height . It can be raised but not without some moderate wrangling. I've worked on quick adjustment schemes but it's so bright in there especially when plants are small it was easier to set it at a finish height and forget it.


I now leave mine fixed with 24" doors. (actually 23 7/8" . lose 1/8" for table saw blade width) My older 4' wide units had 16" doors and the lid could be raised on either side to work on the girls. I may run 32" doors on a bigger plant SCROG run next group and in a 6' wide unit. I'll use 4x600w lamps in the 6'.

Note that when I say 4', 5' or 6' width that is the footprint width or gross width. The actual inside width of the tray is 6" less allowing for leg and tray side thickness. Everything must be scaled and allowances made for material thicknesses.

----------------------------------------------------------------------------------------

GlassMan
Senior Member

Well, I did it. Took me a bit longer than I'd thought mainly because I had to assemble it my growroom because I chose to build a 5x8 and it wouldn't fit through the hidden door. A 4x8 would have....oh well. I've only got one of the lights installed and another just "rigged" for now. I'll finish it and the third light tomorrow. The daughter's at a spend-the-night at a friend's and the wife expects a dinner & movie. I know who the boss is!
Anyway I'm thrilled with the light I'm seeing with this setup. Can't wait till the girls show me how much they like it.

-----------------------------------------------------------------------------------------

keima
Resident Teacher

There are a few things I would like to know.

1. How tall are the "corner legs, and at what height do you attach the reflector?
2. What is the distance from the lights to "ground zero" where the net cups are?
3. How long do you let them veg for?
4. Do you let them just grow, or do you use, LST?
5. I'd like to see the buildup of the Ballast cart as well if you happen to have that.
I have more questions but these will have to do for now.

--------------------------------------------------------------------------
 
page 10 continued,


keef treeez
Senior Member

Hey Keima, Thanks for droppin' in. I've been pretty busy recently. Glad someone still remembers this thread.

Answers:

1) The corner legs are 8' 2x4's. They don't need to be that long but I eventually want to rig a lifting scheme for the reflector from them. Here's the basic elevations. Floor to Tray base=30" Tray sides=6"tall
Door height=24" Reflector attached at 60"(30+6+24) The reflector is then adjusted down slightly to make the door slide nicely and stay in the grooves. The reflector's right now are either 15" or 20" depth(height) I'm in the middle of fine tuning.

2) Bulb to GZ= about 27"

3) Veg time from root emergence from tiny cube to placement=about 2weeks. Keep in mind my veg time starts on that root emergence day not some time down the road when the roots are deemed full enough to "veg" Veg times stated around here must be filtered through the relative sensor.

4) Trialing at least 3 methods, LST(My Bombsai method could be described as HST but I personally don't believe there is any stress introduced until you snap a branch) , SCROG although the net is being used to hold them vertically(2"netpots provide little support) as opposed to using it to train, and medHDSOG @ 6" spacing

5) I'll post the ballast cart buildup when I get to building the next one. Could be a couple months. Stay tuned

Thanks for the interest. I'd be stoked to see someone actually complete one of these tunnels from my instructions. There have been a couple of partial projects. Seems most viewers see it and then want to adapt some element to their current setup. While this is surely fine, the unit is designed from the ground up to be a complete system. My pics show the ease of use and neat layout when employed. It's difficult to view a grow beyond the "growROOM" concept with shit all attached to the walls and ceiling
This was designed to eliminate all the clutter and confine the GROW into a unit that provides atmospheric control, light reflectivity and containment, and a simplified hi-performance hydro system. It's got all of that.
----------------------------------------------------------------------------------------------
keima
Resident Teacher

Thank you for all of that info! If I have any other questions I will be sure to ask. This is a picture of the setup I decided to go with, I know it may be small, but it gives you a general idea. Space is 10' 8" x 19' 3". I'm going to build 2 5' x 8' bloom tunnels, 1 5' x 4' Mother tunnel, and then a small cabinet with 4 4' flouros for the cloning chamber. I have been contemplating over which design to go with and I think I have finally settled on yours. I'm very excited to get this build going, so I hope that when I start it you will come into my thread and help me trouble shoot if I need help building it.

Too bad you're not in my area, you could help me set it up.

-------------------------------------------------------------------------------------
 
PAGE NUMBER 11

keef treeez
Senior Member

Keima, With 19'8" length of room I would arrange the two bloom tunnels end to end and make the veg tunnel narrower/longer on the same side as the cabinet. The shared light in the end to end tunnels is to valuable to lose. Ventilation will be easier with just one fan at each end.

----------------------------------------------------------------------------------------

GlassMan
Senior Member

Keef,
No OOps necessary, I haven't built the table yet , only the reflector. I'll begin working on it in a couple of weeks. I'll be cutting clones on the 26th and will put the SWC table together while they root.

Keef did you consider using foam board (insulation) for supporting the net pots? It comes in 2" thikness which would probably be quite strong, grip the net cups well, and float so that it wouldn't need support from beneith. Just wondering/thinking...

As for raising and lowering the reflector, perhaps something as simple as a length ot 3/4" pipe mounted between the uprights at each end would do the job. One could be "fixed" acting as a nonturning pulley and the opposite one would have 4 support cables/ropes attached. The pipe with 4 ropes you'd crank by hand and the nonturning pipe would just have 2 of the ropes draped over it, one at each corner, and slide up or down. Did that make sense, or did I get tongue-tied? Of course the doors/sides would have to be oversized so the reflector or table would be able to slide. I'd think that you could easily just hang the side panels from the reflector, like curtains. If mylar was more durable you could cover a roll-up window blind with it and that would be the perfect solution for the sides, I don't know how long it would last being rolled up and down a couple of times a day. Just more wondering and thinking....

------------------------------------------------------------------------------------
keima
Resident Teacher

OK, I've been reading this thread and your others over and over for like 3 days straight, and I have come up with some more questions.

1. Your drain system is still a little vague to me. How high is it set up off of the bottom of the table?
2. It looks like in one picture there is a netcup in the drain hole. What is it there for?
3. What are the heights of the two seperate rows of PVC fencing? Where do you get that stuff, because I can't find it.
4. What is the thickness of the masonite?
5. Got any closer shots of the bulkhead fittings used? It's hard for me to see them in the original picture.

I'm sorry I ask so many questions but I am trying to get all of the bugs and minute details out of the way before I start so that I may duplicate your success in design and assembly. Thanks.

-------------------------------------------------------------------------------------------

GlassMan
Senior Member

Hey keima,
I'm in the planning & details phase of building a tunnel too, it looks like a great way to grow. I got the fencing from Lowes a few years ago, it made a great & quick play-pin for our daughter in the the hot shop (gota' keep babies from getting cuts & burns!). The fencing is about 3" thick, from memory. If you can't find it you could easily use pvc pipe with some T's and El's to do the job, I'd guess 1.25" or 1.5" would be a good size to use. It would be handy to have a chop saw when making so many cuts.

----------------------------------------------------------------------------------

keima
Resident Teacher

Garden Treasures PVC 7' x 10' x 22 mil. w/ Free Patch Kit

Item # 61250
Model # WW21902
$34.97


I found this at http://www.lowes.com/
Do you think this would be suitable to use as the pond liner? It's extra thick and could cover up to a 6' x 8' easily.

----------------------------------------------------------------------------------------------

keima
Resident Teacher

Glassman, thanks buddy, I found the fencing at Lowe's.

-------------------------------------------------------------------------------------------

keima
Resident Teacher

Also KT, the soaker hose, what diameter is that? Do you have any pics of them hooked up to the air lines and then the pumps?

I know, I know, too many questions.

---------------------------------------------------------------------------------------------

keef treeez
Senior Member

--------------------------------------------------------------------------------
Originally posted by keima
OK, I've been reading this thread and your others over and over for like 3 days straight, and I have come up with some more questions.

1. Your drain system is still a little vague to me. How high is it set up off of the bottom of the table?
2. It looks like in one picture there is a netcup in the drain hole. What is it there for?
3. What are the heights of the two seperate rows of PVC fencing? Where do you get that stuff, because I can't find it.
4. What is the thickness of the masonite?
5. Got any closer shots of the bulkhead fittings used? It's hard for me to see them in the original picture.

I'm sorry I ask so many questions but I am trying to get all of the bugs and minute details out of the way before I start so that I may duplicate your success in design and assembly. Thanks.
--------------------------------------------------------------------------------


No Problem, I purposely left out finer details like these as I do change and upgrade hardware or configuration regularly. Your gettin the latest now.

1) The cup field is set about 3.5-4" above the bottom of the tray. The net cup is about 2" depth so I can still run as much as 1.5" of nutrient solution in the tray for good flow distribution.(No dead water in the corners) These elevations are all relative. You can make a deeper bath or whatever. The guiding parameter is the water skimming the bottom of the cup when they are first placed.

2) The netcup in the drain hole was used a a temporary riser to raise the water level to skim the bottom of the cups. They can be stacked in the drain 3 or 4 high to give a steady adjustment down as the root systems mature.

3) The PVC fence rails are available from lowedepot and elsewhere.
About $12.00/16' length. They are 1.5" x 5.5" like a 2 x 6 so I rip them down in half lengthwise and cut to length. I use these pieces to set as the first riser rails in the bath. That's a 2.5" rise from the bottom with those and then lay another set of rails across the bath on top of the riser rails to act as joists supporting the cup field. sheet(shower board) I lay that set on their side so the additional rise = 1.5" . So the total rise off the bottom of the tray is 2.5+1.5"=4"

4) The masonite is about 1/8" It comes in 3/16 and 1/4" but the 1/8 is best for this application. Tempered or regular masonite is fine. Whatever is available and cheapest.

5) The Bulkheads are 1.5" ID(inside diameter) for the drain and 1/2" ID for the in-flow fitting. They are available from

http://www.aquaticeco.com/index.cfm/.../6843/cid/1860

6)Soaker hose is the smallest stuff. I belive they call it 1/4" which must be the OD It's hotglued to the bottom of the liner and fed by two lines. I use the cheapo 10.00 airpumps from wallys as they are disposable and output nearly the same volume of air as the GH unit.

Using PVC pipe with some fittings to create a riser structure to support the grow field above the bath is a good alternative if you don't have a table saw and chop saw to cut all that stuff. It's messy.
 
OK here's the walkthrough on the parabola:

First start with your piece of wood 48" x 30" the outline you see on the paper is the same size.

Next make a vertical centerline down the middle of your piece.

The directrix is at the bottom of the page, the vertex is 12" up from that, and the focus is 12" up from that. Mark those points. Next make small hashmarks which indicate ever inch from top to bottom.

Now make horizontal lines across the paper at those 1 inch intervals.
 
Now make a mark 13" from the focus. Now make marks at 14", 15", 16", etc. until you run out of room. Make sure each mark is on the next line up from the previous mark. Complete on the other side as well.

Now connect the dots.

Now make a mark 3" in on either side to allow for your wood. 1 1/2" for one of the skeleton pieces and 1 1/2" for your reflector legs. You can cut this down to 1 1/2" only on either side if you want your legs to be external, I chose the previous so that my tunnel's outside dimensions are exactly 4' x 3'.
 
Now cut out your reflector and you end up with your parabola.

cutting your reflector three inches down from the center helps distribute the light in the parabola better and is the recommended method. This is what it looks like.

MAKE SURE YOU CUT IT LIKE THIS!!! This is what makes it so the light can distribute over such a wide area.
 
Here's some pictures of KT's tunnels so you can get an idea of what the finished product will look like.
 
here's a few more
 

Attachments

  • 20518.jpg
    20518.jpg
    140.6 KB · Views: 1
  • 20519.jpg
    20519.jpg
    153 KB · Views: 1
  • 20520.jpg
    20520.jpg
    147 KB · Views: 1
So let's get into the different pieces shall we??

OK, so now we're going to start with some pics of some of the basic pieces, including assembly pictures.
The first pic is the tray, it's a 4'x3' tray with 2"x6"'s along the edge.

Second pic is a picture of the PVC support skeleton that I made to hold up the showerboard since I couldn't find the PVC fence rails Keef talked about.

Third pic is of the showerboard laying on the PVC skeleton
 
You must log in or register to reply here.
Back
Top