We woodworkers certainly know mitered corners and numerous joinery techniques. They are a regular part of the work we do in our woodworking shop. Among those joinery techniques is the pocket hole joint, a strong joint with many applications.
How about today we mix the two and discuss them as partners in the joining of mitered corners, then? We’ve actually written about this very thing in a past article, although not quite as directly as we will today. You’ll find that previous piece here.
What Types of Joints Use Pocket Holes?
Pocket hole joinery has many uses among the projects we’ve taken on. Certainly, the simplest of joints, like butt joints/ edge joints, are prime candidates for pocket hole joinery.
The pocket holes are drilled in one piece of wood, and the pocket screws are used through the pocket hole and into the second piece of wood being joined. However, pocket holes may also be a good choice for joining mitered corners, whether for mirror or picture frames, door frames, window frames, and such. The planks of a desktop or tabletop may also be a good candidate for pocket holes.
What Are Common Joinery Techniques?
In that previous article mentioned and linked to, we discussed generally the joining of picture frame corners, and we mentioned:
- Biscuits. Oval-shaped pieces of birch or particle board are wood glued up and inserted into slots cut into the two rails to join them together. Once joined, the biscuits are not visible, front or back, on the frame.
- Splines. Rectangular pieces of wood that are wood glued up and fit into grooves cut in each frame rail. They require a bit more work than biscuits, and once joined, splines are visible on the outside of the frame corner.
- Pocket holes. We know these. Recessed holes are drilled in one frame rail guided by a jig made specifically for the purpose, and pocket screws are used to join the two rails. The screws fit in the recessed hole “pocket,” and thus its name.
Of these common joinery methods, we believe the pocket hole creates the strongest joint.
Pocket Hole Tools
If you’ve followed our website, or learned it on your own, or have used the tools yourself, the first name in pocket holes is Kreg. You probably know the story behind the tools, too.
Craig Sommerfeld was building new cabinets for his kitchen, and his wife asked him to figure out a way to hide all the screw holes. He devised the concept of pocket holes and built the first pocket hole jig. This happened in the late 1980s.
Today, Kreg Tool, located in Huxley, Iowa, manufactures a variety of jig styles and configurations. It also manufactures the drill bits and screws used in pocket hole joinery. The Kreg jig is well-known in woodworking.
The Kreg jig serves as the drill guide, and the jigs with multiple guides enable the woodworker to fit the pocket holes where they need to be for the workpiece. Jigs can come with one guide, two guides, and three guides, spaced so as to provide different options for drill hole placement on a workpiece.
Pocket Holes on Mitered Joints
Mitered joints Involve the joining of two pieces of wood that have been cut at 45-degree angles and, when joined, form a 90-degree angle corner – picture frames are the obvious example. Most often, a miter saw is used to make those cuts.
The long point of the frame rail is called the toe; the short point is called the heel. Toe to toe, heel to heel, the two pieces are joined to form one corner of the frame.
If pocket holes will be used as the method to join and strengthen the corners of the frame, it requires close attention to detail and depends on the wood pieces being joined. But it is certainly possible.
Testing Pocket Holes First
It is always prudent to test before you begin working on the project pieces, and this joinery is no exception. Scrap wood comes in handy, and using the same dimension wood for testing will tell you how best to approach pocket holes on miter joints for your project.
Pocket Hole Placement on Mitered Corners
We see three possible placement choices when joining mitered corners using pocket holes and screws:
Two parallel pocket holes in the same piece. If the dimension allows, two parallel pocket holes might be a good choice. A multi-guide jig offers different spacing for those pocket holes, and if the workpiece has the room for two holes, it’s an easy configuration to drill.
Two pocket holes at different angles in the same piece. You may decide that one hole perpendicular to the miter cut and another at an angle might provide greater strength to the joint. Or, perhaps dimension might dictate that approach. Either way, two pocket holes, and screws will give a strong joint.
Two pocket holes, one at the toe end and one at the heel end. If dimension permits, this will provide great strength to the miter joint, too. A pocket hole in each piece pointing toward the other is a good way to achieve this approach.
Before making any pocket hole, though, be sure to check on the back of the jig. If any part of the drill guide hole is showing, be sure not to use that guide to drill. Otherwise, you’ll be drilling through the edge of the piece of wood.
No matter which way among these three you choose, we recommend you also use both glue and clamps. While the jig will hold the workpiece together while drilling, clamps will hold the workpieces together at the correct angle while you glue and screw the pieces together.
Kreg jig models, as we said, range from a single hole to three holes in various configurations, clamping, and kits. Prices start as low as $15 for a single-hole jig and drill bit and up to $140 for a three-hole jig kit. For the professional woodworking shop, there are even pocket hole machines that run $400 or so.
Pocket hole screws come in two choices and multiple lengths. The choices include coarse-head screws for softwoods and fine-thread screws for hardwoods. The length of screws will depend on the size of the pieces being joined.
Screws come with a square drive for greater torque. The flat bottom of the counterbore stops the screw when it has reached its end point, and the pilot hole the bit drills will guide the screw into the second piece of wood exactly where it will need to be.
The process, then, is very straightforward once you have decided where to drill the pocket holes. The jig kits come with clear instructions and charts showing the right screws to use and the right depth of drill depending on the woods being joined. That it is a miter joint being worked on, rather than a butt or edge joint, doesn’t change the basics of pocket hole joinery.
Kreg’s own video shows you how easy it is to use pocket holes on miter joints. This short video shows you how. In this video, the choice was 2 parallel pocket holes – the workpiece was dimensionally able to accommodate the choice.
Miter joint, butt joint, edge joint – the principles are still the same. With a miter joint, just a bit more planning and aforethought are required, but the process is simple and direct.