Upholstery is a whole different ballgame than woodworking. But because this specific upholstery task didn’t seem too hard, I figured even though I had no experience at all I could probably get a decent result without too much work. Turned out I was right. The finished cushion works well, looks good, and it took me well under an hour to compete.

Visit the fabric store

I selected a piece of 2″-thick rubber foam, which was more expensive than the other options but was the perfect density for this project. I added a few layers of polyester craft batting over top of the rubber foam. This was sold in a larger size and is fairly thin, so I was able to fold it into three layers for my cushion. These layers provide a more even look and shape to the finished cushion.

Next was the fabric. The hard part was selecting the colour and pattern. Let the people assisting you at the fabric store know what you’re using the fabric for, and they’ll be able to help you choose an appropriate fabric for the project. Make sure to choose something that won’t fray easily when you wrap it around, and staple it to, the plywood base. In hindsight, I used a fabric that was a bit too stretchy, and I had to add a lot of staples. I would opt for a thicker fabric next time. All told, I managed to keep the price tag for fabric, rubber foam and batting under $100.

Start with the plywood base

Cut a piece of 3/4″-thick plywood to the width and length you want the cushion to be. I left 1/2″ between the edges of the cushion and the edges of the table. Next, slightly ease all the edges of the plywood base. I opted for a 1/8″-diameter roundover bit in my trim router, but sanding the edges heavily would also work.

Lay the plywood base on top of the rubber foam and cut the foam to the exact same size as the base. I used a plane blade, as it was sharp and could cut deep enough. Next comes the batting. Lay the rubber foam over the plywood base, and measure from the underside of one side of the base to the bottom of the other side, then add about 1″ to that dimension. Repeat for the other direction, then cut the batting those sizes. I removed a 2″ × 2″ square from all four corners of the batting, in order for it to more evenly wrap around the corners.

Add the fabric

Cut the fabric to size next. You want it to cover the upper surface of the cushion, wrap down all four sides, and extend at least 3″ under the plywood base. Because I was afraid I would cut the fabric too small, and ruin it, I left a few extra inches on each of the four sides.

Place the fabric face down on a flat, clean surface, then add the batting, rubber foam and plywood base on top, centered over the fabric. Pull one edge of the fabric up and over an edge of the plywood and tack it in place with a few staples. Unless your fabric is really stretchy, you likely don’t have to pull it as taut as you’d think. Repeat for the other three sides, then carefully check if the fabric is tight enough. If either too tight or not tight enough, you can remove the staples and start over.

If you do a lot of upholstery work a cordless nailer can be very helpful. The Grex GC1850 is the smallest, lightest, most powerful 18g brad nailer available and shoots brads from 1/2″ to 2″.  A narrow tip size and very small nail hole makes trim work easier and faster. The GC1850 uses common AAA batteries for triggering, (expect 50,000 shots from a set of batteries.) No expensive, bulky, specialized batteries required.  Grexusa.com

With the four sides started you can then add a few more staples around each of the four sides, working around the base and pulling the fabric evenly. Don’t staple the fabric too close to the corners.

Dealing with the corners

There are a few ways to approach the corners, but as long as you finish with even, tidy, taut corners I don’t think there’s a wrong way. First I pulled the fabric that was centered over the corner taut, and stapled it in place. Then I adjusted the fabric between the corner and the straight sections so it was snug, and there was an even pleat on the edge of the cushion, and stapled the fabric in place, before repeating on the other side of this corner. There was a bit too much fabric near the underside of the corner, so I used scissors to remove a bit; just don’t remove too much, or there won’t be enough fabric to be properly secure the corners. Repeat with the other three corners, and you’re done. Use a hammer to ensure the staples are driven into the plywood base fully.

The underside of my cushion didn’t look professionally done, to be quite honest, but since it was going to be fixed to the table nobody would ever know. I’m happy with the finished look, but I’ve already caught myself thinking of what fabric I’ll use when I reupholster the cushion in a few years. At that point I’ll likely be able to reuse the foam and batting, so new material with be my only cost.