Introduction: Road Sign Fence
For the 2010-2011 academic year, I have been the construction manager for the Greensboro, Alabama chapter of YouthBuild. YouthBuild (http://www.youthbuild.org) is a national program funded by the Department of Labor that provides low-income young people a chance to study for their GED and acquire trade skills, all while earning a small stipend for their labor. This fall, my students and I built a fence adjacent to our campus. It encloses a playground constructed by the Rural Studio (http://www.ruralstudio.org) in 1997 and currently used by a daycare center. The local county and state highway engineering offices donated old road signs, which we then cut, sanded, filed, and drilled to create pickets. Using jigs and a self-organized assembly line, the students manufactured nearly a thousand pickets for roughly 225 linear feet of fencing. By cutting and randomly re-assembling the signs, the graphics were broken and rebuilt into a new collage of abstract symbol and color.
Unfortunately, the new Congress has voted to completely eliminate YouthBuild's funding in the next budget, potentially causing all 273 YouthBuild affiliates to shut their doors once their funding runs out. In 2007, the most recent year figures were available to me, YouthBuild cost the federal government $50 million dollars. This represents a mere .00039 percent of America's current deficit, yet, by some studies, YouthBuild generates $9 of economic output for every $1 spent on it. We are working hard to get America's economy back on track by training skilled workers and helping young folks help themselves rise above their circumstances. Please help us by signing this online petition in favor of YouthBuild's continued funding: http://www.change.org/petitions/save-youthbuild-act-now-2#?opt_new=t&opt_fb=t
I would like to thank all the students who participated in building the fence last fall: Raheem Ameen, LaDarius Carlisle, Anthony Davis, Nathaniel Davis, Quency Edwards, Shineka Gilmore, Jamie Gray, Jonta Greene, LeDarius Kennedy, Percy Lawson, Markel Lewis, Marshe Lewis, Andrew Mitchell, John Mullen, Marcus Pasteur, Marcus Richardson, Korderra Robinson, Tyisha Thomas, Dai-Samona Waller, Eric Watkins, Shakena Webb, Melvin Webster, Eric White, and Roderick Williams.
I would also like to thank the YouthBuild staff: Jon Carter, Dakesha Greene, Dan O'Hara, RaMell Ross, Ron Ross, Carter White, and Sara Williamson. Thanks to RaMell for the first ten photos and several more throughout (http://www.ramellross.com)
You will need these materials:
Approx. 80-100 3' x 3' aluminum road signs, reasonably flat and bullet-hole free
6" x 6" x 10' pressure treated posts (for corners and sides of gates)
4" x 4" x 10' pressure treated posts (for intermediate posts)
2" x 4" x 10' pressure treated horizontals
3" galvanized screws
1-1/4" galvanized screws
You will need these tools:
Circular saw/table saw
40+ tooth carbide saw blades
Carbide drill bits
Step 1: Pickets
First, locate some road signs. You'll need a lot. We had the local county and state highway yards donate their old signs, as they are very difficult to recycle. The reflective coating on the aluminum makes it tough to melt them down without letting off a lot of toxic fumes or letting a lot of impurities into the metal.
Given 3" wide pickets, with 1-1/4" gaps, it takes 22 pickets to run 8' horizontally; it takes 44 pickets to run 8' if the fence is two tiers high, or 6' tall. Accounting for the kerf (amount of material that must be subtracted to account for the width of the sawblade), you can get 11 pickets out of a 3' sign. However, a lot of signs or portions of signs had to be discarded due to bullet holes, excessive dents or bending that couldn't be hammered out, or other damage.
We cut our signs by clamping a guide board to the sign to run a circular saw against, then slicing the aluminum with a carbide finishing blade. Carbide teeth are hardened, and the finish blades have a lot more teeth, making for a smoother cut. It was quite loud, but it cut surprisingly smoothly. Once the signs got too small to hold and cut safely with the circular saw, we fed them through an old table saw with a carbide blade on it. Aluminum is a very soft metal, and cuts quite easily.
Then, each picket had four mounting holes drilled in it, using a jig to position the holes. Unfortunately, I don't have any good pictures of the jig, but it was basically a wood frame that held the picket, with a movable guide piece to precisely place the holes.
The most important step, safety-wise, especially since the fence was going around a daycare, was to sand the edges to remove any burrs, and knock down the corners with a file. 60-80 grit sandpaper will sand aluminum quite nicely, and a standard metal file rounded off the corners. We went over each one with bare hands to feel for any missed spots, then bundled them in stacks of 22.
Step 2: Demolition
Once you have a bunch of pickets made, go ahead and knock down the old fence. We had to move incrementally, because the playground couldn't be without a fence at any point; accordingly, we knocked down one section at a time, and boarded it over temporarily with plywood when necessary.
The old fence was in awful shape; splintered, rotten, and sagging. It was a safety hazard to the kids in the daycare, so we flattened it, saving what posts we thought could be re-used.
Step 3: Posts
Pull a string line down the length of your proposed fence, measuring, marking, and dropping a plumb bob every eight feet. Mark the spots for each post with some spray paint or a stake.
Dig your post holes at least eighteen inches deep; we tried to go at least 24" when we had posts long enough. We were re-using a lot of posts from the old fence, so sometimes our footings were a little shallow. Here in the south, frost isn't an issue, so the depth is less important. Rot is the biggest obstacle to longevity; we poured our concrete to the surface of the soil to protect the posts from ground contact as much as possible. In a northern climate, keep the concrete below the surface of the soil, burying and tamping around the footing. This will help prevent frost from heaving the concrete out of the ground.
At the bottom of each hole, throw a little gravel or broken up masonry or concrete to help with drainage. Mix Quickrete and fill the hole; we also threw broken-up block and masonry in the mix to save a little on concrete mix. Bring the front face of the post to the string; plumb in both directions and brace out to a stake to hold the post vertical while the concrete cures. Use 6" x 6" posts for the corners and on either side of the gates, for strength; use 4" x 4" posts elsewhere.
After the concrete cures, measure up from the ground to the desired height of the post, then cut at a slight angle with a Sawzall. The angle will drain water off of the end grain of the post, helping to prevent rot.
Step 4: Frame
The frame is simple: run 2" x 4"s horizontally at 6" from the ground, 36" inches from the ground, and at the top of your posts, which should be around 66" for a 6' fence. All measurements are on center. Disregard level, as the fence will follow the contours of the ground. Just measure up from the ground at each post, and connect the dots. Attach all horizontals with 3" galvanized deck screws for strength.
For the gates, make a rectangular frame with two uprights and three horizontals, matching the rest of the structure. Put a diagonal across the back to brace and square it. The diagonal isn't strictly necessary, as the signs can do a pretty good job of bracing the door framework. Add hinges, then signs; this way, the signs hide the hinges nicely.
Step 5: Pickets 2
To put up the pickets, first pull a centerline down each horizontal with a speed square or chalkline. Starting in a corner, align the mounting holes on the centerline. Pop a screw in one hole; hold the level to the picket and plumb it. Make sure the bottom of the picket is aligned with the centerline on the middle horizontal. Put in the other three screws. Repeat for the picket below.
Cut a spacer block to your desired picket spacing (we went with 1-1/4") and put that against the picket you just mounted. Chock the next picket against the other side of the spacer block, pin, plumb, screw, and repeat.
For a more finished look, the students suggested we use the pickets we cut off the edges of the signs -- the ones with rounded corners -- to set off each eight-foot section. We set the four edge pickets, then worked towards the center of each eight-foot section, ensuring that the fence looked symmetrical if our spacing ended up a little off between the last two pickets.
When you're done, a quick pressure wash will brighten 'er up.
Our fence adds a bold color to the campus by day, and a ghostly reflectivity at night. The aluminum will last forever, and the pressure-treated lumber should last a decade at least.