Copper is an ideal outdoor material for garden structures. It has a warm, natural look, whether shiny or tarnished. It lasts for years without upkeep. And it's easy to work with and relatively inexpensive.
We built this copper garden trellis from standard 1/2-in. and 3/4-in. type M copper plumbing tubes. We'll show you a unique joining method that allows you to solder the tubing together without fittings. To simplify the process, we'll show you how to assemble a simple 2x4 jig to keep the tubes aligned while you solder them. Don't worry if you've never soldered copper. This project is a great place to learn, since you don't have to be concerned about critical plumbing joints leaking. If you goof up and one of the joints lets loose, just resolder it.
Even working at a casual pace, you'll be able to complete this project in a weekend. You can pick up all the materials and tools at a home center. You'll need a tubing cutter, propane torch, propane canister, emery cloth, roll of solder, flux and flux brush for the soldering work, and a hammer and saw to build the jig. If you want to anchor the trellis in the ground as we show in Photo 15, buy a 10-ft. length of 1/2-in. electrical conduit (EMT). You'll find it in the electrical department.
If you object to the lettering on the copper tubes, remove it with steel wool or an abrasive nylon pad. Then mark and cut the lengths of copper needed following the Cutting List (below). You could use a hacksaw to cut the tubing, but a tubing cutter is much easier to use and results in a cleaner cut.
Start by snugging the wheel onto the tube at the cutting mark (Photo 1). Spin the cutter once around and tighten it a little. Continue spinning and tightening until the tube is cut.
After a few tries, you'll know how much to tighten it each time for the most efficient cutting. If you plan to build several trellises, buy a top-quality tubing cutter. A good cutter will last a lifetime and give better results with less effort than an inexpensive cutter.
Figure A and Photo 5 show how to build the jig. While it isn't absolutely necessary, the jig simplifies the task of keeping the tubes aligned while you solder them together. You can also design your own trellis. Start by drawing the design on graph paper. Then transfer the tubing spacing to the 2x4s and build the jig as we show. Make sure to slide the copper grids back and forth in the jig as you solder opposite sides to avoid getting the flame too close to the wood.
In order to connect the tubing without using plumbing fittings, we show a method of bending the end of one tube to fit around the other. Start by building two bending forms (Photo 2) using 6-in. lengths of steel pipe (gas or water).
Build one jig with 3/8-in. pipe for bending tubes to fit around 1/2-in. copper tube, and another with 1/2-in. steel pipe for ends that fit around 3/4-in. tubing. Bend nails over the pipes to hold them in place on the hardwood blocks. Practice the bending technique (Photo 2) on scraps of tubing to get the knack. It's OK if you don't get a perfect fit. The solder will fill small gaps.
Photos 5 – 11 show how to solder and assemble the tubes. The key to a good soldering job is to thoroughly sand with emery cloth, flux the contact zone and apply just the right amount of heat.
The heat is right when solder flows easily into the joint. Remember to heat the joint for about 10 seconds first, then feed in about a 2-in. length of solder. Let the copper melt the solder, not the torch. If you heat the joint for too long, the flux will burn and the solder may not stick. If this happens, let it cool. Then sand and flux the joint and try again. Be careful to let the copper tubing cool before touching it or removing it from the jig.
Pay attention to the orientation of the spear points when you're soldering. It's easy to get them twisted slightly or facing the wrong way. But don't worry, the rustic look of this project is what makes it interesting, so it's OK if it's not perfect.
The 2x4 jig makes assembling the frames almost foolproof. Start by setting the four 30-in. tubes between the outermost pairs of nails (Photo 6). With the tubes in place, it's an easy task to mark where they intersect the 3/4-in. upright tubes. Then sand and flux the marked areas. Make sure to orient the curled spear points in the same direction. Measure 8 in. from the top of the upright to the top of the horizontal tube and secure it with a spring clamp (Photo 8). After you solder the first joint, remove the clamp and solder the remaining three joints. Remove the half-built frame from the jig and form the opposite ends of the crosspieces (Photo 9). Repeat the steps in Photos 6 – 8 to complete the main frame (Photo 10).
Build the ladder frame the same way. Measure down 12 in. from the top of the spear to the center of the first tube. And then solder the five 18-in. tubes to the upright tubes (Photo 11). Slide the tubes all the way to one side to solder the first tube. Then slide them to the opposite side to solder the second upright. Otherwise you'll burn the wood with the torch. Remove the completed ladder frame from the jig and reinstall the main frame between the nails.
Clip the ladder frame back into the jig on top of the main frame. Mark all eight points where the two frames intersect. Mark both frames. Then remove the ladder frame and flip it over to sand and flux the marked areas.
Also sand and flux the marked areas on the main frame. Replace the ladder frame and solder the two frames together (Photo 13). Repeat this process for the two additional tubes. There are no nails in the jig for the final two tubes. Position them according to the dimensions in Figure B and use spring clamps to hold them in place for soldering (Photo 14).
Lay the trellis across a scrap 1x4 and mark the position of the 3/4-in. tubes. Drill two 5/8-in. holes centered on these marks. Use the 1x4 to hold the 1/2-in. EMT in position while you pound it in. Use a level as a guide to make sure your tubing is vertical.
Depending on how hard your soil is, drive the 5-ft. tubes about 18 in. into the ground. Install the trellis by sliding it over the tubes and pushing it into the ground to level the horizontal tubing. Complete the project by planting your choice of climbing vine at the base of the trellis.
KEY QTY. SIZE & DESCRIPTION
A 2 80” lengths of 3/4” copper tubing
B 4 30” lengths of 1/2” copper tubing
C 2 69” lengths of 1/2” copper tubing
D 5 18” lengths of 1/2” copper tubing
E 2 57” lengths of 1/2” copper tubing
Call 811 to locate underground lines before you drive these tubes into the ground.