I started this year by building two above ground garden boxes, they stand about two feet tall and are about twelve feet long.
Immediately, I ran into a problem. For the days were warm and the growing season was still about two months out and we were getting occasional frosts at night. So I could plant things and hope for the best or wait it out, about two months later I started planting.
I thought about how nice it would be if I could have planted earlier and lamented not incorporating some sort of greenhouse into my original planter project. Then I got to thinking on how I might be able to go about adding a temporary greenhouse to get an earlier start next year.
It needed to be something fairly sturdy and most importantly it needed to have almost no storage footprint as I don't have the room to store two 3-4' high 12' long greenhouses after the growing season kicks off. I looked at some plans that involved PVC supports and while they were decent they ate up more storage room than I was comfortable with. I thought back to my youth when I made mummy for Halloween out of chicken wire but dismissed the notion of flexible metal fencing in general as it would have been too unwieldy. Eventually settling on thinner metal support bars, the only problem is by themselves they would have been flimsy and likely to have had a predisposition to fall over.
The eventual idea became a pair of metal support arches with temporary linkages to give them more stability. Since the linkages are temporary that means that storage wise the arches and clips will probably take up less useful space than the plastic for the greenhouses.
The parts still need to be printed, tested, revised (probably several times) and eventually released on Thingiverse with along with an additional instructable. This represents the initial design for the clamps set up to work with 1/4" metal support bars. This is the beginning of how to make temporary greenhouse support clips