Flatten Wide Boards without a Big Jointer
This past June, my wife and I purchased our first house-a 1900 stucco home with a basement that has a long history as a workshop. Recently, while beginning the process of designing my new basement shop, I came to the realization that I would never be able to afford a jointer larger than 8-in. Sure, I could purchase a 100-year-old, 12-in. beast like my colleague Matt Kenney, and spend a month rehabbing it but to be frank, I just don’t have the time.
In my five years at Fine Woodworking, I’ve been spoiled by the massive size of our SCMI jointer here in the shop at Newtown, CT. I’ve never had any problem milling any piece of stock for any of my projects. Our 16-in. monster is a dream to use but again, way out of my price range. So what’s a guy to do when his jointer just isn’t big enough for the workpiece he needs to mill? I suppose I could flatten a face by hand but I’d rather use a machine for rough milling and save the handwork for final smoothing.
Several years ago, FWW ran a Methods of Work tip by reader Jerry Lyons titled Glue on Rails to Flatten a Wide Board. This technique uses a planer to flatten the first face of a board, as opposed to a jointer. Lyons begins by cutting his workpiece to the shortest length possible and then proceeds to joint each of the two edges straight. Next, he places the board down on a flat work surface, cupped side up and uses wedges inserted at the ends, near each corner, to level the board until it doesn’t rock. Finally, he glues on rails to the board’s edges so their bottoms rest flat atop the work surface, gluing and clamping them into place. After the glue has cured, he removes the clamps, double checks that the rails are still registering against the flat work surface (he takes care of high spots with a bit of handplaning-nothing major) and sends the piece through the planer.
I’ve always been curious to try the technique and decided to run a “proof of concept” test using a 13-in. DeWalt planer and an 8-in. wide maple scrap. The proof is in the pudding. Have a look at the photos above for the play-by-play.
Here's the workpiece I ran my test with--a rough-sawn piece of maple.
I began by cutting a few wedges at the bandsaw.
I also milled up two strips of hardwood, slightly wider than the thickness of my test board.
My first step was to straighten the two edges of my workpiece. I used a jointer plane to smooth and flatten them.
Next, I set my board down on a flat work surface--cupped side up--and used the wedges to level the workpiece atop the flat work surface. My goal was to get rid of any rocking.
I read the grain direction from the edges. Since I knew I'd be covering those edges up in the next step, I figured I'd mark my feed direction for the planer on the top of the board.
Next, I glued and clamped those two strips to either edge of my workpiece, being careful to ensure that their bottom edges were in contact with my flat work surface.
Then it was just a matter of running the entire assembly through the planer. Once I flattened the top face, I flipped the board end-for-end and brought it down to final thickness. The rest of the milling process is the same as always.
And there you have it. I set the board atop the dead-flat infeed table of our monster jointer here at work (ironic, I know) to check for flatness. I also checked for square and consistent thickness. Sure enough, the technique worked like a charm. I will most certainly be using it in future projects!