Back in the winter of 22-23 we had a heavy snow after a long warm period. I still had a shade cloth over my 24’ by 20’ greenhouse. It caught the snow. The roof collapsed. As if have said several times, I learn a lot by making mistakes. That left me with the wall structure of a greenhouse but no roof and a lot of twisted pipes. By the time the cleanup was completed, there was no time or money to rebuild the whole structure. Besides, it was not in the best place for a greenhouse in the first place. Time for plan B.
Sometime earlier I had joined the Huckleberry Range Community Collective (HRCC). They have a tool sharing network and have a Facebook page and group. One of the tools offered is a hoop bender, a device to bend steel pipes and make a hoop house greenhouses. This sounded like a good plan B. I knew that they came in different sizes. A friend had proudly showed me his 10-foot-wide greenhouse and offered to let me use his pipe bender sometime before my greenhouse collapsed, so I declined at the time. Somehow that width stuck in my mind and I assumed that the two hoop benders were from the same company and had the same width.
As many things in this adventure, things were not so simple. My friend had a pipe bender from Bootstrap Farmer. (BootstrapFarmer.com) The one from HRCC was from Johnny’s Seeds (Johnnyseeds.com). Either one costs around $100 but Bootstrap has a shipping cost. A nice thing about both websites is that they are very specific about what pipe to use, something I was not getting from word of mouth. For the 10’ hoops, you need 1 3/8 inch “chain link fence top rail pipe”. The nearest source people remembered was Ziggy’s in Spokane. Talking to several stores in Colville I came up empty. Then I realized that I might be able to special order it and was able to do that through Builder’s Shopping Center in Colville. The pipe can come in 20’ or 10’ lengths. I asked for 10’ knowing I could strap that to the top of my car. A little math made me conclude that I needed 2 10’ lengths for each hoop in a 10’ wide hoop house and 6 hoops for a 20’ long house. So, 12 lengths of pipe all together. Cost $204. Not bad. I had salvaged pipe for a top tie rail, if you don’t, it is worth adding 2 more lengths of pipe.
The pipe arrived a week later. I took it home and unpacked it. 6 of the lengths had swaged ends. Those ends fit nicely into the ends of the 6 unswaged lengths. Somehow the source knew exactly what was going on and made it so I could piece together 6 20 foot pieces of pipe. The circumference of a 10’ circle is 31.41 feet so a half circle would be 15,7 feet giving me a little over 4.3 extra feet that I could use to raise the hoop over two feet off the ground on each side for a height of 7 feet, ( 5 ft radius of a 10 ft hoop plus 2 ft each side), plenty of clearance in my view.
Off I went to get the pipe bender from HRCC. It turned out that their bender was for a 12-foot hoop, not a 10 foot. That threw me off. Also, the pipe bender was actually made out of bent pipe itself which seemed weird since I had the Bootstrap version in mind. A little bit more math and I was back on board. The type of pipe was the same and there was still enough for a 6.5-foot clearance plus another 40 feet of floor space in the greenhouse. 12 feet was a better option.
The next decision was how to mount the bender. The Johnny’s website showed it bolted to a picnic table where the force would be sideways and it was assumed that the table would not warp or move. The Bootstrap sight showed it mounted on the wall of a shed so you could pull down on the pipe being bent. I went for the shed guessing that it was going to take a lot of force to bend steel pipe. Each bender came with a “cheater bar” that fit onto the pipe to give extra leverage for the last few feet, a good hint that a lot of force was in order.
It sure was. Luckily, I had extra pieces of pipe left from my previous greenhouse disaster that slipped over the 1 3/8” pipe and gave me a lot more leverage. Even with that I was regretting not doing more chin-ups later in life. The fulcrum of the bend is wherever the pipe touches the bender. The most force is at either end. If you want a section left straight, let it hang over one end. Bend a few inches of the pipe at a time and move the bent part of the pipe out the back of the bender. This gives you less and less leverage as you get to the end, hence the cheater.
My previous greenhouse used pipes pounded in the ground to position those standing up. So, I cut up some of my spare parts pipe to serve that purpose. That proved necessary since the 12’ hoop wants to spring out to 14’ until the ends are stuck in the ground pipes. Hoops are not Legos. They tended to flop a little one way or another and top centers didn’t line up exactly. Although not shown in some examples, having a top trail over the whole array lines them up more exactly and provides a little boost in getting water to run off or snow to slide off if placed above the hoops on the center line. I was glad to have some salvaged pipe for that purpose and the “bender” actually helped straighten it out.
Having the bone structure of a greenhouse is really just the beginning. Wrapping it, providing doors, making ways to ventilate etc. are all important and variable. That could be called Plan B(a).
BTW if you could use some pipe pieces for ground pipes, leverage or need self-tapping bolts to tie things together, I still have spare parts.