Mitring is an essential technique for woodworking projects that require precise angle cuts. Mitre cuts allow you to join two pieces of wood or trim at an angle, like at the corners of a picture frame. While mitre saws are specially designed for these types of cuts, you can also make mitre cuts using a standard circular saw.
Page Contents
- 1 What is a mitre cut?
- 2 Can you cut mitres with a circular saw?
- 3 How to make mitre cuts with a circular saw
- 4 Tips for better mitre cuts with a circular saw
- 5 Cutting different types of mitres
- 6 Alternatives to cutting mitres with a circular saw
- 7 Advantages of mitre saws vs. circular saws for cutting mitres
- 8 Safety tips
- 9 Conclusion
What is a mitre cut?
A mitre cut is an angled cut made across the width of a piece of wood or other material. Mitre cuts allow two pieces to be joined together at an angle – most commonly at 90 degrees to form a corner joint. The most common mitre cuts are:
- 45 degree mitres – Used to join two pieces of trim or wood at a 90 degree corner
- 90 degree mitres – Creating a straight joint between two pieces
- 30/60 degree mitres – For specialty angles and multi-sided projects
Precisely matching mitre angles are critical to achieving clean looking joints and corners. Even the slightest mismatch in the angles will result in gaps or overlaps once the pieces are joined.
Can you cut mitres with a circular saw?
Yes, circular saws are capable of making mitre cuts. However, it is more challenging than using a powered mitre saw due to the following factors:
- No angle guide – Circular saws lack angle presets and stops for common mitre angles like 45 and 90 degrees.
- Less precision – Freehand cuts are harder to line up exactly.
- Blade deflection – The spinning blade can drift slightly during the cut.
Making accurate mitres requires careful setup and workholding with a circular saw. But with the right techniques and jigs, you can achieve great results.
How to make mitre cuts with a circular saw
Here is a step-by-step guide to making mitre cuts with a circular saw:
1. Set up a mitre guide
Use a triangular mitre guide, speed square or DIY jig to guide your saw at the desired angle. Ensure the guide is secured firmly against your workpiece edge to prevent any shifting during the cut. Mitre boxes are also very useful for holding the material at an exact angle.
2. Align and mark your cut line
Align your cut line against the edge of the mitre guide and use a pencil to mark the line across the face of the board. Remember your blade will cut about 1/8 inch from the edge of the guide.
3. Secure your workpiece
Clamp your workpiece securely to your work surface to prevent any movement during the cut. Use additional backer boards or spacer blocks to support the offcut piece.
4. Set your saw depth
Adjust the blade depth on your circular saw to cut just slightly deeper than the thickness of your material. A depth of about 1/4 inch deeper is ideal.
5. Make your cut slowly and smoothly
Line up the saw base plate with your cut line. Power up the saw and ease into your cut gently. Move the saw smoothly and steadily along the mitre guide to make the cut. Let the blade do the work!
6. Check for accuracy
Temporarily fit your two mitred pieces together to check the accuracy of the joint. If there are any gaps, you can make minor adjustments by recutting along the same line.
It takes practice to master mitre cutting with a handheld circular saw. Working slowly with sharp blades and the right guides is key to getting neat joints. Minor gaps can be concealed using wood filler or by hiding end grain seams.
Tips for better mitre cuts with a circular saw
Here are some helpful tips to improve the accuracy of your mitre saw cuts:
- Use a carbide tipped blade designed for fine finish cuts
- Ensure your saw’s base plate and mitre guide edge are exactly at 90 degrees to the blade
- Cut slowly and watch the cut line as you go to avoid wandering
- Support the workpiece on both sides of the cut near the cut line
- Make several practice cuts in scrap material to dial in your angles
- Use wedge blocks to support the offcut piece and prevent binding
- Apply painter’s tape along the cut line to reduce tear out
Cutting different types of mitres
The techniques for cutting mitres are similar for both 90 degree corners and angled joints. Here are some tips for common mitre cuts:
45 degree mitres
– Set your mitre guide to exactly 45 degrees using an angle gauge or protractor
– Cut mitres in both pieces of trim or wood to be joined
– These are commonly used for door or window trim
90 degree mitres
– Align your mitre guide perpendicular to the face side of the board
– Cut both joining pieces with precise 90 degree mitres
– Used for right angle picture frames and box construction
30/60 degree mitres
– Set the mitre guide to the desired angle – 30 or 60 degrees is common
– Make identical cuts on all pieces being joined
– Used for specialized angles like hexagons or octagons
No matter what type of mitre cut you need, take your time setting up and align yourself perfectly square to the blade for the cleanest cuts.
Alternatives to cutting mitres with a circular saw
While circular saws can accomplish mitre cuts, the following tools are better suited for precision mitre work:
Mitre Saw
- Blade and fence are set up for angled cuts
- Quickly set angles with positive stops
- Hold material precisely with built-in vises
- Clean, splinter-free cuts
- Compact benchtop models available
Table Saw
- Use the rip fence and mitre gauge together
- Allows precise adjustment of cut angles
- Good for longer boards
- Requires careful setup and workholding
Mitre Box
- Guides the saw at precise angles
- Built-in stops at common mitre angles
- Usually limited to trim or smaller stock
- Very simple to use
Investing in a good quality mitre saw or table saw ensures accurate results and easier mitre cutting. But common woodworking circular saws can also be used successfully.
Advantages of mitre saws vs. circular saws for cutting mitres
Mitre saws have some key advantages compared to circular saws when it comes to mitre cutting:
| Mitre Saw | Circular Saw |
|---|---|
| Built-in preset mitre angles | Mitre angle must be set manually |
| Positive stops for repeatable accuracy | Harder to replicate the same angle |
| Workpiece well supported near the cut | Requires additional workholding |
| Cuts are clean and precise | More potential for blade deflection |
| Dedicated mitre function | Less specialized tool |
| Easier to line up perfect joints | Mitre alignment takes more skill |
For most mitre work, a good mitre saw is faster, safer, and produces more accurate results than freehand circular saw cuts. But for larger material or one-off cuts, circular saws with mitre guides can achieve decent mitre joints.
Safety tips
Cutting mitres with power saws demands focus and care to operate them safely. Follow these tips:
- Use sharp, undamaged blades
- Don’t force the saw during the cut
- Avoid awkward hand positions that reduce control
- Secure workpieces with clamps not your hands
- Wear eye and ear protection
- Clean up sawdust frequently to avoid slipping
- Support large boards to avoid pinching the blade
- Follow all manufacturer safety instructions
Rushing through mitre cuts or making unsafe circular saw cuts greatly increases the risk of accidents or injuries. Working slowly and deliberately is always the smartest approach.
Conclusion
Cutting accurate mitres is certainly possible with a standard circular saw, provided you utilize careful setup, jigs and workholding. But for flawless mitres without frustration, a dedicated mitre saw is highly recommended for most home woodworking projects. Whichever saw you choose, always focus on safety and cut slowly for the best mitre cutting results.