DIY Low Tunnel Hoops
April 21, 2010
So I’ve been really into the idea of extending the gardening season as well as protecting my cabbages, Brussels sprouts and broccoli from the dreaded white butterfly. I’ve been scouring the interwebs for a good project to take ideas from and ended up at Johnny’s Selected Seeds Quick Hoops Bender. Cool tool, eh? It’s also a cool $69 plus $32.45 for shipping. At just over $100 US, I couldn’t justify buying it and shipping it to Canada to only make a few hoops. I set myself to finding a do-it-yourself (DIY) solution.
When I first tackled this project I thought 3/4″ PVC pipe was the way to go. I’ve worked with it before when building props for Halloween (my other hobby) and I was used to the fittings and cutting of pipe, etc. After reading blogs and posts from different gardeners who’ve built their own low tunnel hoop houses, I realized that the PVC would be too fragile to overwinter in my cold climate. If I was going to build something, why not build something that will last?
Enter electrical metallic tubing (EMT), a.k.a. galvanized electrical conduit. These metal pipes are used to run electrical wiring in houses. All the sites I’ve read (US sites, I should add) mention how a 3/4″ – 10′ length of EMT only costs about $2. Great, I thought, this will be a cheap experiment. Checking my local hardware store, I found out the same pipe costs $8.48. I looked online at Lowe’s USA and found their price was $3.27, a whopping 2.6 times cheaper than here in Canada (btw, 1/2″ pipe up here is $4.98 and $1.87 down there. Ugh.). I decided the next trip across the border would have to include a stop to Lowes.
In the meantime, I needed to find a way to bend the EMT without the use of the Quick Hoops Bender or a pipe bender – a handy pipe-bending tool that I don’t have and don’t want to purchase. The problem would be to create the arc that the 10′ pipe would need to have so that the ends of the pipe would have a 4′ distance. Basically, I was trying to figure out how to recreate the pipe in this photo.
To start my experiment, I bought one 1/2″ EMT, one 3/4″ EMT and one 3/4″ PVC pipe, all in our high Canadian prices.
Reviewing the Quick Hoops Bender manual (PDF), revealed that each hoop was to be extended 16″ beyond the end of the bender, i.e., there would be 16″ of straight EMT on either ends of the pipe. I pounded scrap rebar into the ground until it was at a height of 16 inches:
I pounded another piece of scrap rebar into the ground 4′ away:
I took my 3/4″ PVC bendy pipe and stuck the ends on the rebar:
Stepping back, I had a 10′ long and 4′ diameter arc!
It’s not as perfect-looking as the Johnny’s picture but I didn’t care. I dragged out a large piece of scrap plywood and placed it behind the pipe:
I took a Sharpie and traced the inside of the arc onto the plywood:
My next step will be to drill screws at 18″ intervals along the line to create a jig around which to bend the pipe. Having two different diameter pipe will help me figure out which one is more suitable for this experiment. Once I’ve got a few hoops made, I can then put them in my garden and cover it with remay to protect all my brassicas.