An Inexpensive Cyclorama ("sweep") Background

In 2004, I discovered paper backdrops and immediately fell in love with them. I've been addicted to the cornerless backdrop look ever since. One day, however, I realized I was spending a ton of money on paper rolls - at $40 per roll plus $40 shipping, it can add up fast.

When I bought my studio in 2006, I started thinking of different ideas for durable backdrops. I saw one guy who bought a 12 foot wide piece of vinyl flooring, mounted it with an oak stiffener and hook-eyes, and hung it on a wall (much like a paper sweep only lots tougher) - the vinyl flooring idea was attractive but the flooring would have cost about $300 and it weighed a ton and was a pain to hang. It was around that time that I started thinking in terms of making something out of wood. Why not? I'm not a fine woodworker but I can build stuff that is durable and not too unattractive.


(bare wall with blackboard removed)

My studio is an old elementary school that I've turned into a fortress of solitude/laboratory of evil/photography studio/5000 square-foot closet. I built the sweep in the 3rd grade classroom, after first knocking down the blackboards and clearing the wall.


(subflooring laid out to make base)

Since the floor of the studio is concrete and tile, it gets mind-bleedingly cold in the winter. I thought I'd put subflooring down to give a little insulation as well as to serve as a base for the sweep. So I purchased 5 sheets of oriented strand-board and laid them out on the floor, after lifting a few tiles and putting heavy urethane glue to hold them down to the concrete. The pieces of strand-board are set a distance from the wall, based on the curvature of the sweep; you can see the gap between the floorboards and the wall; that's the part of the sweep that will "float" off the floor. It was critical to align the floorboards perfectly with the wall so that the sweep's curve would be even - if it was cockeyed at this point the surface material would land at an angle.

To get the alignment, I put glue down, dropped the floorboards into place (with beads of glue between them) and then carefully measured the edge distance from the wall. Then I experimentally curved a piece of the surface material to make sure that it looked about right when there was another piece on it up to the edge. I probably could have calculated this carefully but I just eyeballed the curvature and measured the distance on the floor.

I laid the subfloor out widthwise because the surface was going to go lengthwise. I made a saw cut down one piece of subfloor so I could offset them; I didn't want there to be any places where a gap in the subfloor would align with a gap in the surface.


(construction layout of subfloor and bottom of surface)

I used a big caulking gun and a couple of tubes of industrial slow-setting adhesive. If I ever have to take this thing up I am going to be in trouble because it's held to the floor with a serious amount of glue, and the concrete is porous - it's definitely stuck.


(surface material and floor glued together and weighted with whatever I could find to put on it)

If I could do it all over again #1: When I glued the surface material to the subfloor, I used construction adhesive. If I could do it all over again, I'd use foaming urethane glue (AKA "gorilla glue") so that the foam would come up through the gaps and fill them.

Once the floor was drying nicely I studded in the wall with 2x4s to support the surfaces. At the top is a large piece of heavy plywood to serve as a header-board; I thought that I would support the weight of the surfaces with a line of screws across the header.

If I could do it all over again #2: when I put the studs up, I made cross-pieces to help keep the surface from flexing. If I could do it all over again, I would just put up twice as many studs, or maybe an underlayment of 1/4 plywood. When I finally completed the sweep, the pieces on the wall flexed slightly and they are very hard to fill and sand. Using twice as many studs would have allowed me to put the gap along one of the studs and use foaming urethane glue.


(Studs, mounted to the wall with screws and glued to the cinderblock)

Once all the studs were mounted and even with the wall, I checked to make sure they weren't bowed out from the wall by sliding a large aluminum angle-bar up and down. In a couple spots I had to hammer thin wedges of wood behind the stud to bring it out from the wall, or tighten the screws to pull it in. Trust me: take your time making the studs as perfect as you can and you'll be happy in the long run.

If I could do it all over again #3: One of the studs turned out to be slightly warped after I had mounted it and the glue cured. In order to make the surface flat, I had to plane material away from the wood, which took me about an hour. If I could do it all over again, I'd be more careful about picking lumber that was straight.


(Levelling the surface)

To mount the upper surfaces, I used a spirit level and mounted my aluminum bar horizontally across the studs by the simple expedient of screwing it in with a couple of drywall screws. This made mounting the upper surfaces quite easy - I just had to rest it on the cross-piece then climb up and screw it into the header-board. Then I glued and screwed my way down each of the studs. The material is fairly solid and doesn't flex much but it does flex slightly. I wish I had used twice as many studs.


(Surface pieces mounted and levelled)

Here you can see that I added cross-studs to stiffen the edges of the surface pieces. To install the cross-studs all I did was put glue on the back and edges, then screwed horizontally through the stud with a thin long screw. The cross-studs are to keep the edge of the surface from flexing or drooping. Two years later, it seems to have worked.


(test-fitting the curve)

Do Not Forget: to fill, sand, and finish the upper surfaces before you install the curved pieces. It is pretty easy to sand while you can stand on a ladder, but once the curved pieces are in, you won't be able to put a ladder there and you'll be hating your entire existence.

Here what I am doing is test-fitting the piece that's going to fit into the curve. With the upper and lower surfaces mounted and glued, the curve pieces will just snap right up against the edges of the upper and lower surfaces. At this point I considered cutting some heavy plywood sheet into curves to match, so I could mount them underneath (just glue them) for extra strength. As it happens, it seems to be strong enough.


(reinforcements!)

I cut two long strips of the surface material and glued them to the underside of the center curved piece, then glued and screwed the center piece in place. The reason for this reinforcement is not just to stiffen and strengthen the joint, but to act as a dam to force the foaming urethane glue to fill the crack as it expands.


(foaming urethane glue fills cracks and eliminates the need for caulking and spackling)

If I could do it all over again #4: When I constructed my sweep, I filled all the cracks with spackle and then sanded the spackle down with an orbital sander. This made a horrible mess and the surface isn't as smooth as I'd like it to be. If I could do it all over again, I'd make much more heavy use of the foaming urethane glue. When I was finishing it, I discovered that you can just shave it down with a sharp knife and paint right over it for a perfect no dust surface.


(Done! Too shiny!)

This is the test-shoot with the new sweep. You'll notice right away that there's a pretty serious reflection off the surface. With a flash, this will completely ruin your shot! I finally went to the paint store and asked for the most matte-surfaced stuff that they had. It turns out to be the most expensive paint they sell (go figure!) Sherwin-Williams' "cashmere" interior matte latex. It's gorgeous stuff, though.

To paint the sweep I use a pole with a paint roller. The first coat I put on was primer, but now I just paint layer over layer (there's about 30 layers of paint on it now) it takes about 1/2 gallon for a thick coat and, if I am not changing the color, I just touch up the areas where people walked.

Total construction time for this project was about 5 hours over the course of 3 days.