One of the best things about this trellis is that it's easy to build with just basic tools and off-the-shelf materials from your local home center. We used cedar for our trellis, but any rot-resistant wood will do. The scrollwork is made from No. 6 solid copper wire (the kind used for grounding electrical panels). It's expensive, though—about $100 for enough to make scrolls for all four sides. However, you can save $75 by making scrolls only for the "show" side, which lowers the cost of the trellis to $125.
The legs and center posts are 2x2 cedar, and the horizontal rungs that connect them are 1/2-in. copper pipe. You can make the cap like we did or buy one made for deck and fence posts.
Cut the four legs to length, set them on sawhorses and clamp them all together so that the tops are even. Measure, mark and drill 5/8-in.-diameter holes 28 in., 41-1/2 in. and 59 in. from the tops. Each hole is drilled 1 in. deep at a 10-degree angle. Use a guide block cut at an angle to help guide your drill bit (see Photo 1). You can cut a guide block by setting your miter saw at 10 degrees. If you don't have a miter saw, pick up a protractor (about $10) at a home center. The drill should "lean" toward the tops of the legs. Now flip each leg 90 degrees, clamp them together again and repeat the process.
Using a pipe cutter or hacksaw, cut six pieces of 1/2-in. copper pipe to length for the rungs. Note in the Cutting List that two sides of the trellis have slightly longer rungs (C, D and E). Cut those now. Temporarily assemble one side of the trellis—two legs and three pieces of pipe. Tap the legs to get the pipe seated. The tops of the legs should be almost even.
After cutting the center posts (B) to length, use a miter box or miter saw to cut points on the ends of the center posts. A line marked around all four sides will guide you (see "Cutting Pointed Ends,". Lay the center post on top of the assembled side (see Photo 2). Be sure the post is centered. Mark the post for the pipe holes, then transfer the marks to the other three center posts and drill the holes at 90 degrees. Drill from one side until the point of the spade bit pokes through, then stop and drill through from the other side. This will give you cleaner holes.
Build two sides of the trellis. Put the longer sets of pipes (C, D and E) through the holes in the center posts, get them centered, and then place the ends of the pipes in the legs. Lay an assembled side on sawhorses with the remaining holes in the legs facing up. Place a bolt or old screwdriver in each hole and whack it with a hammer. That will crush the end of each pipe, locking it into place and making space for the adjoining pipe. Cut the remaining pipe rungs (F, G and H) and then fit the rungs and remaining center posts between the two assembled sides to form the complete trellis structure. Tighten any loose joints by putting a bit of epoxy in the pipe hole.
Make a bending jig out of a 2x12 or a scrap piece of plywood at least 11 in. x 18 in. Enlarge the patterns in Figures B, C and D on a copier until the dimensions are correct, and tack a pattern to the jig (see Photo 3). Nail two 10d finish nails on both sides of the scroll shape to hold the wire (see Photo 3).
Cut one piece of wire to length. Measure from one end to find the point that goes between the two finish nails (see pattern drawing), mark that spot, and lay the wire on the jig so your mark is between the two nails. Using your hands only, bend the wire to the shape on the pattern (Photo 4). There should be a few extra inches of wire on each end to give you something to hold.
When you've got the first half bent to shape, snip the end. Put a weight or a clamp on the part you've done, then bend the other side. You don't have to be fussy about matching the pattern; close is good enough. If your first scroll was a success, cut the remaining piece of wire and bend the rest of the scrolls.
For each of the three different size scrolls, do one for practice before cutting the remaining wire. If you have trouble, cut the wire a little long so you’ll have more to work with.
Lay the trellis on its side and use fence staples to attach the scrolls to the 2x2s (Photo 5). Be sure to get the pairs of scrolls on each side of the trellis to be symmetrical (a right and a left), and to reverse the direction between the lower and the middle scrolls (see Figure A). When all the scrolls are attached, stand the trellis up, grab a stepladder and sand the tops of the legs flat and even (Photo 6). If the pieces vibrate too much, tape them all together with duct tape.
Cut the lower and upper cap pieces (M and P). For the facets (angled sides) on the upper cap (P), start with a 1-ft. piece of 4x4 so you have enough wood to hold on to while you cut the facets. Then trim off the finished cap piece. When both cap pieces are cut, drill pilot holes in the lower cap (M), nail it on, then glue on the upper cap (P) with construction adhesive or epoxy.
Dig the bottoms of the legs into the ground and get the trellis plumb. You'll have to do it pretty much by eye. If your location is windy, anchor the bottoms of the legs in the ground. One way is to bend a couple of 3-ft. pieces of 1/8-in. rod into a U-shape so they can be driven in around the legs. Then fasten them to the legs with fence staples and cover with dirt or mulch.