Backyard Aquaponics
A place to discuss aquaponics

A while back there was some discussion and interest in building greenhouses/hoop houses for aquaponic/hydroponic systems. Since most of us are do it yourselfers or working on a budget I thought I would share a source for a bending tool(s) for making greenhouse/hoop house frames. The source is www.homemadegreenhouses.com If you aren't able to bring up his home page he can be found under a google search for "hoop house frame bending tool". The price for the tool starts at $89.00 US with $15.00 S&H in the US. The basic tool comes in three sizes (depending on size of hoop desired) and he offers one for making a 21 degree angle which will allow you to construct a peak roof, straight walled style structure. Just an FYI for those of you wanting to move your system inside for the winter!
Kevin

hi Moke, need to edit and take away the trailling "dot" after the .com for the link to work mate

Thats a very simple handy thing....

My brother and I built a greenhouse with a simple tube bender
http://www.northerntool.com/webapp/wcs/ ... 70_605_605

Ems - I have one of those benders and was considerring making a tunnel type GH with it. How hard was it to get the arches right. Did you bend every few inches or less frequently. Cna you explain how you went about it.

THanks.

The one I cited is made in three different sizes and 3 models in each size. The largest one makes 16 and 20 foot wide arches. The difference in the models is the cheapest ones require you to make 5 bends in each 10 foot section, the middle one requires three and the most expensive one only one. The bender works on 1 3/8" chain link fencing top rail, so it might be a bit larger material than most of the electrical conduit benders I have seen. To make the 20 foot hoop it requires you to use three sections of top rail, so that should mean you will have roughly a ten foot center height.

Unfortunately the site does not have the "Plans" or "Tools" section operational. I am not sure if he supplies them with the tool or if he can send them to you in downloadable PDF format.

I am thinking about buying a couple of them to build myself a greenhouse and a storage building. The storage building will be covered with corrugated metal, while I will cover the greenhouse with corrugated polycarbonate sheets. I know I would do better with double or triple wall polycarb, but the prices are too prohibitive for me to use it at this time.

Thanks for the edit correction Rupert. I am so used to putting in a period after a sentence.
Kevin

The one Ems cited is one that is used more in muffler and auto shops. I am sure it will work, but the problem is in getting the bender up high enough to allow you to feed the work in without getting your tubing down onto the ground or floor and having it limit your arch. The one I think I am talking about is a lot more like an electric conduit bender. It is a metal arch that you slide one end of the tubing into and then have another pipe (black iron "gas" pipe) you insert into a socket which you then use to give you leverage to arch the tubing (the tubing is laying flat on the ground or floor of your work area).
Kevin

Actually now that I remember, we made our own bender based on that idea -- with a bottle jack. We used it on it's side and did three bends -- one for the top, and two for each side. -- basically a house shape with 3 chamfered corners. We used 2" shedule 40 water pipe because we wanted it to be strong enough to handle snow loads. Then we used 3/4" and 1/2" EMT conduit for the truss and diagonal braces.

Kevin - the bottle jack benders (like the one I have) can be laid on their side while doing the bending (like ems says. Ems - I want an arch - so may have a play to see how hard it is to get a consistent one by dending using however many strokes every however many inches.

Get the calculations right vb

The correct number of strokes for every inch - and it helps to be ambidextrous too

Don't forget to hold your tongue correctly.

I think it will be very difficult to get smooth consistent arches with the bottle jack bender.

One of the problems with laying the bottle jack on its side is the return of the piston after the bend is made. When it is laying on its side you do not get the benefit of gravity pushing down on the piston and the load on top of it, so without a return spring you will have to push it back down after each completed bend. Most bottle jacks are a one way force system, and do not return like a two way hydralic cylinder does.

As far as number of strokes, what you do is use a steel carpenter's square and a setable angle to use as a gauge for you to estimate the degree to which you want to make your bend. Just remember some of the simple geometry you were supposed to learn back in the 8th grade. A circle is 360 degrees, a half circle is 180, a quarter circle is 90 and an eighth is 45. So if you want to build your frames with a 12/12 pitch, your peak will be a 45 degree angle and your two sides will be 22 and 1/2 each. If you are going to a 6/12 pitch it will be a 30 degree angle at the ridge and each of the sides. I hope my simple geometry is right, if not, I am sure someone will help me correct it. (Thanks)

Kevin

I am sorry but I gave you the wrong degrees of angle. (What can I say, I failed 8th grade math, but was in the 98th percentile in science.)

Your angles need to total 180 degrees, sooo... For a 12/12 pitch the top angle will need to be 90 degrees and the side angles will need to be 45 degrees. For a 6/12 pitch the top and side angles will be 60 degrees each.

My error dawned on me when I was in the shower, funny how sometimes just being in/near water can make you think more clearly! I didn't have time to make my correction until now, due to work. Sorry if I made anyone waste some time or materials.

Kevin

[quote]Since most of us are do it yourselfers or working on a budget I thought I would share a source for a bending tool(s) for making greenhouse/hoop house frames. The source is www.homemadegreenhouses.com If you aren't able to bring up his home page he can be found under a google search for "hoop house frame bending tool"

Hi all........
An interesting note, Look at www.hoopbenders.net these folks invented these bending tools their price is just $39.99 thats a big difference.