how to join two pieces of wood at 45 degrees

In woodworking, getting the angles right makes all the difference, especially when you’re aiming for a sharp 45-degree joint.

It’s not your everyday joint – it’s for those special projects where you need a perfect angle, like a neat cabinet corner or a stylish octagonal frame.

But here’s the trick: it’s all about making two cuts at 22.5 degrees each. Sounds challenging? Don’t worry. We’ve got you covered with a step-by-step guide to tackle this head-on.

Types of Joints in Woodworking

There’s a whole world of ways to join wood, each with its tools and tricks. But not all joints make the cut when it comes to a 45-degree angle.

Here’s a quick rundown:

  • Butt joints: Just two pieces of wood glued end-to-end. Simple, but not suited for our 45-degree goal.
  • Edge joint: Think of wood planks glued side-by-side. Great for tabletops but falls short for 45-degree angles.
  • Miter joint: The go-to for picture frames, using 45-degree cuts. We’re on the right track with the miter saw for our project, but we’ll dial it back to 22.5-degree cuts.
  • Pocket hole joint: Not a match for our angle. We’ll skip this one.
  • Mortise and Tenon: A solid no for this task.

While we want every joint we form to be a strong joint or at least one that will be durable and last a long time, some joints don’t necessarily have to be that strong. 

We simply want them to be durable if they do not support any weight.  For instance, the corner of a cabinet or countertop or a multi-sided picture frame simply needs to last.

The Miter Saw Cut

Miter Saw Gauge

Our miter saw will be part of the project and be used to create the 22.5-degree cuts. 

While 45-degree cuts are the usual ones we use the miter saw for, it is capable of making other cuts, too.  If your miter saw can make bevel cuts, too, that is another option.

You may be able to make the cuts simply by setting the angle of the saw blade to a 22.5-degree angle.  

This is becoming a more common angle to cut in woodworking, as 45-degree corners have many applications – the octagonal picture frame mentioned earlier, where 8 pieces are jointed at 22.5 degrees each to form the frame; or, and here’s an unusual one, the component pieces joined to form an original segmented turnery piece before it is attached to the lathe.  

Return to the miter cut, set the miter gauge to 22.5 degrees, and make the cuts.  

If the shape or size of the workpiece makes another method a better alternative, use the bevel-cut ability of the miter saw to make that cut. Simply set the bevel angle gauge to 22.5 degrees, or 67.5 degrees (do the math, turn the workpiece, and you have your 22.5-degree angle), and make the cut.

The Table Saw Cut

No worries if you don’t have a miter, saw, or a miter box with a handsaw (old school) but have a table saw.  You can make the same cut on the table saw with a little bit of effort and a couple of accessories.

Cut your workpiece to size, needing only the 22.5 angle cut to be made.  Then, set the blade angle.  For this, rely upon a digital angle gauge instead of a protractor, as it will be more accurate and reliable.  A slightly off-cut will leave a gap when the two pieces are attached.

A vertical router sled attached to the table saws fence guides the pieces through the blade.  It will need to be close to get a good cut, a quarter inch.  Be sure you are wearing all of your safety gear – goggles, face mask, gloves, and maybe even hearing protection gear.

This is a difficult cut, but if you approach it slowly and carefully and are skilled in using your table saw, it is a viable method of getting your 22.5-degree angles on your workpieces.

How To Join The Two 22.5-Degree Angle Cuts

45-Degree Angle Joint

With the cut workpieces in hand, we turn now to the joinery.  While other woodworkers will have their own way of joining these pieces, we have a fairly straightforward method that we think you’ll find worth considering if you need to form a 45-degree joint.

What You’ll Need To Form a 45-Degree Angle

  • Materials Needed
    • Wood glue
    • Clamp blocks
    • Spring clamps or spring miter clamps
    • Hot glue
    • V-nails or brads
    • V-nailer
    • Brad nailer
  • Notes on Preparation:
    • While the list of materials is extensive, it’s necessary due to the complexity of forming an unusual 45-degree joint.
    • Clamp blocks, essential for this task, are custom-made for the specific project.
    • The size of clamp blocks depends on the workpieces being joined.
    • These blocks are triangular and cut at a 22.5-degree angle, identical to the workpiece angle.
    • It’s advisable to cut clamp blocks simultaneously with the workpieces to ensure consistency.

Joining The Workpieces For A 45-degree Angle

You will be attaching the clamp blocks to the workpieces at the end of their 22.5-degree cuts.  They will serve only a temporary purpose, so you’ll attach them with only hot glue, not wood glue – a craftsperson’s glue from a glue gun.  Just a dab or two will be enough to hold it in place for its temporary task.

Glue the two workpiece ends and join them.  Grab your spring clamps, and attach one of them to the top of the clamp block; adjust the workpieces until they are aligned, and then attach the second spring clamp.  Let them sit until the glue dries and your 45-degree angle joint is formed.

An Alternative To Regular Spring Clamps

You could use a spring miter clamp as an alternative to the spring clamp.  You’re more likely to have spring clamps in your workshop, though, and they are more than adequate for the task.  We wrote about spring clamps and spring miter clamps recently, also, and you’ll find that article here.

Securing a 45-degree Angle Joint

You’re not quite done yet.  The clamp blocks will come off with a little tap from a hammer or mallet and a scrap piece of wood.  Put the scrap piece against the clamp block and give a little tap to dislodge it.  

There will be some residue of hot glue on each of the workpieces that you can remove carefully with a sharp chisel.  Light sanding will remove whatever little remains after that.

Depending on the purpose of the 45-degree angle joint (decorative or weight-bearing), you may want to secure the joint further with either a brad or two or a v-nail.  A filler of some sort can be used to fill the holes and then sanded down to create a smooth surface, either for staining or painting.

Clamp blocks may be new to you, or perhaps you are interested in creating your own that would be reusable and will not need to be hot-glued to a workpiece.  In that case, we found a video that will be very helpful and make the task of creating your workshop’s clamp blocks for all future projects where you have angles other than 90 degrees to form and clamp.

The math is pretty easy for creating a 45-degree angle, and the method and process for doing so, including the actual joining, is not technically difficult.  Don’t let the odd angles throw you off or make you choose another project.  In woodworking, there is always a way.

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