I think the earth augers are overkill and only make sense if you have the equipment to drive them already. A hand-driven metal T-post/fence post would work just as well for less money. You could also use t-posts to make end walls without those guide wires, which are great for tripping over and hard to mow around.

The weakness of the structure is having plastic hoops 6' apart. Normally, with roll-up sides, you have a 2x4 hip board along each side. That adds a lot of stability. Their design at least needs side purlins. It's also a waste of money to use metal pipe for the top purlin. It might as well be pvc if your hoops are pvc. The metal purlin clamps are expensive, too. Cable ties and duct tape would work as well for less money. Take the money you save and reduce the spacing between hoops to 4'.

Real nice way to make hoops if you have a number of people to help. Purdue has ten or so people helping them when they do these videos. We have seen first hand how they build these things with several students assisting. things like this may make someones thesis paper.
james

Maybe I should have posted on my other thread. I have galvanized hoops 13ft wide x 6.5(ish)ft tall, they were originally 3ft apart in CCA (or maybe it's creosote?) treated baseboard, but I can't dig out 90+ holes 3ft apart in my ledge. Don't have end wall (they were pretty much falling apart), some hipboards might be usable but they were pretty small (I'd have to walk out back and measure, but I think they might even be 1x2 as I recall, not 2x4), I do have metal purlin that came with the hoops.

So I'm just looking for inexpensive way to anchor this thing - not sure how much of the baseboard is still in good shape, hoophouse started 135ft long but I don't have quite that much space, was thinking putting up a couple of smaller ones side by side (just 1 for now), or using the extras for a "garage" for the riding lawnmower, etc.

Being able to move the hoophouse (if I make it much shorter - say 39 ft) would be a bonus, and I am just looking for season extension, not winter harvest.

You're right, I'd have to look into renting the driver for the augurs.

I do have the guy who has some sort of copper azole 2x8's and 6x6's asking me if I'm interested, he says no boric acid in them so I don't have to worry about boron, just the copper (I'm trying to stay "organic" though not certified), I was just trying to get away from having to use wood where it touches the ground.

I would use rebar to keep the supports in place and use a hammer to get them in the ground-this is what we use for our hoop house which is of similar design.

So no baseboards required? Just maybe buy some more top rail and make purlins for the sides? I do want to use 2x4's for hipboards so I can attach gutters and downspouts for rain barrels, but I can use untreated painted lumber (or even spring for Trex, since they're not structural and don't need much) for those.

Just trying to avoid any possibility of chemicals leaching into ground/water since I would like to try to keep as close as possible to organic standards.

I would still use baseboards. They help keep the hoops in place.

I don't like Johnny's tunnel bender for EMT because it is for a 6 foot wide low tunnel and I want mine 8-9 feet wide to cover 2 beds. mother Earth News has a homemade bender. How does it work and can it make any length or what? See link

Here is a link that might be useful: self made roller

I realize this thread is several months old, and is "cold", but I just came across it and am tempted to respond anyway. I plan to build several low tunnels for use this Spring, and probably for use this Fall as well. I am considering several different designs. I am still in the learning process, but I have a couple of comments.

"I don't like Johnny's tunnel bender for EMT because it is for a 6 foot wide low tunnel and I want mine 8-9 feet wide to cover 2 beds."

The problem with that is that the EMT is only 10 feet long, so trying to span an 8 or 9 foot bed with a 10-foot tube means you can bow the tube hardly any at all. The EMT tube just isn't long enough. You would need at least 12 feet and probably 14 feet to cover 8-9 feet wide. I have never seen EMT longer than 10 feet, although they should be able to make it longer if they wanted to.

Incidentally, the bender you are referring to isn't really Johnny's. Johnny is just getting it from Quick Hoops and re-selling it.

I think Mother Earth News would be responsible for providing more information about their bender.

ZM

We used chain link top-rail, so that you can add as many sections as you need. Using a bender is hard to make sure that each of the hoops are exactly the same as the others. My FIL was great doing things like this, he would bend one, then build a jig for the others to fit into. That way, he would make sure that all were the same. Of course, he's don't around any longer, but was taught by builders in the early 1900s, before any machine-made became popular.

I've been working with top rail lately.

What did that jig look like? Was it built to hold one piece of bent top rail, or the entire hoop? I understand the concept, but I'm unsure about the best way to do it.

I was thinking about making all the hoops at once, then using fence posts driven into the ground to hold the hoops as they are stacked on top of each other. The fence posts would make the jig.

Each of his jigs were different. He was a builder, and he built some of his own rafters/trusses for some of his buildings/houses.

Bending all at once, I doubt if it would work, too much slipperage. You always make 1 at a time, but each would be exactly the same. Lots of measurements, including angles. I've seen him and his sons bend pipe, it was interesting to watch. I think it was alot of skill and a good eye.