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Cutting MDF: Which Saw Gives the Cleanest Edges?
For straight cuts in MDF, the best choice is a circular saw or table saw fitted with a tungsten carbide-tipped (TCT) blade with plenty of teeth. For curves and cut-outs, use a jigsaw with a fine blade for wood or sheet material. Cutting MDF produces a lot of very fine dust, so always work with dust extraction and a dust mask.
The right saw for MDF depends mostly on the shape of the cut. Below you will find which saw suits which job, which blade to fit and how to keep coated boards free of chips.
What will you learn in this article?
- Why is MDF different from solid wood?
- Which saw should you use for MDF?
- Which saw blade should you use for MDF?
- Cutting coated or lacquered MDF without chipping
- Cutting MDF straight without a guide rail
- Is MDF dust harmful?
- Common mistakes when cutting MDF
- Frequently asked questions about cutting MDF
- In short: cutting MDF
Why is MDF different from solid wood?
MDF (medium density fibreboard) is made from fine wood fibres pressed together with glue under high pressure. It has no grain, hardly splinters and has the same density all the way through. That is why you can cut very clean edges in it. The downside is that the glue in MDF blunts saw blades quickly and the dust is extremely fine.
Which saw should you use for MDF?
| Saw | Best for | Blade |
|---|---|---|
| Circular saw | Straight cuts in large boards | TCT, high tooth count (roughly 40 to 60 teeth on a 160 to 190 mm blade) |
| Table saw | Accurate rip cuts and repeat cuts | TCT, high tooth count |
| Mitre saw | Skirting board, battens and narrow strips cut to length or at an angle | TCT, high tooth count |
| Jigsaw | Curves, cut-outs and shapes | Fine blade for wood or sheet material |
| Handsaw | A few short cuts | Fine teeth, hardened blade |
Circular saw
For long, straight cuts across a sheet of MDF, a circular saw is the quickest option. Run it along a guide rail or a straight batten clamped to the board and you will get a clean line. A cordless circular saw, for example from the Maxxpack 18V range, cuts through the usual MDF thicknesses without trouble. Check the specifications of your saw for its maximum cutting depth before you start on thicker boards.
Jigsaw
A jigsaw is the best choice for curves, rounded corners and cut-outs, such as the opening for a basin or a socket. Choose a blade with fine teeth for a neat cut and set the pendulum action low or switch it off. A laser guide or a clearly marked cutting line helps you stay on course. Long straight cuts are harder with a jigsaw, because the blade can drift.
Mitre saw
If you are cutting MDF skirting board or strips to length and at an angle, a mitre saw gives the most accurate result.
Handsaw
For a single short cut you can use a handsaw with fine teeth. A hardened blade stays sharp for longer, but even that will blunt faster in MDF than in softwood. For bigger jobs, a power saw is far more comfortable.
Which saw blade should you use for MDF?
TCT or chrome vanadium?
Always choose a blade with tungsten carbide-tipped teeth for MDF. Tungsten carbide is a very hard material that stands up to the abrasive glue in the board. Chrome vanadium (CV) blades are cheap, but they go blunt very quickly in MDF, so keep them away from sheet material.
Number of teeth
More teeth give a smoother cut. For a circular saw blade of around 160 to 190 mm, 40 to 60 teeth is a good guide. A blade with fewer teeth cuts faster, but leaves rougher edges.
Tooth shape
- Alternate top bevel (ATB): good for uncoated MDF and solid wood.
- Triple chip grind (TCG): better for coated or lacquered MDF and melamine, because the surface layer chips less.
A general-purpose TCT blade will also cut chipboard, plywood and hardwood, but a blade designed for sheet material gives a cleaner finish.
Cutting coated or lacquered MDF without chipping
Bare MDF hardly chips, but coated or painted boards do. This is how you prevent it:
- Use a sharp TCT blade with a high tooth count.
- With a circular saw or jigsaw, place the good face down. The blade cuts upwards, so the top face is the one that chips.
- With a table saw, place the good face up.
- Run masking tape along the cutting line.
- Set the cutting depth so the blade only just comes through the underside of the board.
- Use a guide rail with an anti-splinter strip if you have one.
Cutting MDF straight without a guide rail
- Clamp a straight batten or aluminium profile to the board as a fence.
- Measure the distance from the edge of the saw's base plate to the blade, and position the batten that distance from your cutting line.
- Support the board fully, for example on a sheet of rigid foam insulation or on battens either side of the cut. That way the blade does not pinch and the offcut does not drop away and snap off.
Is MDF dust harmful?
MDF dust is very fine and gets deep into your lungs. It also contains glue residue. Take these precautions:
- Connect the saw to a vacuum cleaner or dust extractor.
- Wear at least an FFP2 mask, and preferably FFP3 if you are doing a lot of cutting indoors.
- Wear safety glasses and hearing protection.
- Clean up the dust with a vacuum cleaner with a fine dust filter, not with a broom.
- Cut outdoors where you can, or in a well-ventilated room.
Common mistakes when cutting MDF
- Using a CV blade or a blunt blade, which leaves ragged edges and makes the saw run hot.
- Not supporting the board, so the saw pinches or the edge breaks off.
- Placing the good face of coated MDF on the wrong side.
- Cutting without dust extraction and a dust mask.
- Cutting long straight lines with a jigsaw without any guide.
Frequently asked questions about cutting MDF
Is a jigsaw suitable for MDF?
Yes, especially for curves and cut-outs. Use a fine blade for wood or sheet material and set the pendulum action low or off. For long straight cuts, a circular saw is more accurate.
How many teeth should a saw blade for MDF have?
For a circular saw with a blade of around 160 to 190 mm, 40 to 60 teeth is a good choice. More teeth give a smoother cut. Larger blades for a mitre saw or table saw have more teeth.
Why does my saw blade go blunt so quickly in MDF?
The glue in MDF acts like an abrasive on the teeth. Blades made of ordinary steel or chrome vanadium wear out very quickly as a result. A tungsten carbide-tipped blade lasts much longer.
Can I have MDF cut to size?
Many DIY stores and timber merchants offer a cutting service for sheet material. That is handy for large, straight pieces, especially if you do not own a circular saw. You can then cut curves, cut-outs and small adjustments yourself with a jigsaw.
In short: cutting MDF
Cut MDF straight with a circular saw and cut curves with a jigsaw. Use a TCT blade with a high tooth count rather than a CV blade, and choose a triple chip grind for coated MDF. Support the board well, check which face is up and always work with dust extraction and a dust mask.
