This particular bench is 18 3/4″ tall, 6′ long and 12″ deep. The bench top (the seat) and legs are made from 1 x 12 poplar. Because of the length, the side rails are 1 x 6 to support any weight in the middle — plus the height of the rails is 1/3 of the overall height of the bench making for visually pleasing proportions. For a shorter bench, a 1 x 4 could be used instead. The round holes in the legs are 6” from the bottom, which combined with the rail height, divides the legs into thirds (6 + 6 + 6 = 18). I used poplar for the bench because it is widely available in 12” widths and it is great for painting.
It’s time to get all of the parts nice and smooth. Sand all of the pieces up to 150 grit. This leaves a little texture for the paint to stick to. If you plan on staining yours, sand to 220. I also like to use a hand plane on the edges, instead of sanding. To get in the notch in the legs, I wrapped a piece of sandpaper around a piece of 1/4″-thick wood.
Glue plugs in the side screw holes. The difference between plugs and using a dowel is that the plugs will be long grain wood and the dowel will be end grain wood. The long grain runs in the same direction as the side rails. And do yourself a favor. Don’t use cherry plugs if you don’t have to. When the glue is dry, level off the plugs. I find that a hand saw and hand plane works perfectly.
Clean the whole thing using a damp rag or mineral spirits. This does two things. One, it removes sawdust and two, it raises the grain. In a lot of species of wood, when it gets damp (like when painting) the loose grains stand up, making for a rough surface. Pre-raising the grain helps to minimize the effect.