A slide compound mitre saw will help you get alterations or additions to your home done faster and better. And the cost of the machine is likely to be minimal, compared with the price of your project's building materials.

Types of mitre saw

There are 3 main types of mitre saw, each with different capabilities:

  • Mitre saw - the basic type can cut through timber at an angle, generally ranging from 45 to 90 degrees.
  • Compound mitre saw - this can do mitre cuts as above, but at the same time it can bevel cut at a vertical angle of between 45 and 90 degrees. In other words, the saw blade can angle and tilt. Compound mitre saws are sometimes called drop saws.
  • Slide compound mitre saw - this can do everything a compound mitre saw can do, and more. The saw head can also slide horizontally, to allow wider pieces of timber to be cut. The sliding movement is achieved using single or dual sliding rails.

What to look for

If you're thinking of buying a slide compound mitre saw, here's what you need to consider.

Blade size
You can get a slide compound mitre saw in various blade sizes. Bigger blade-diameters mean the machine can handle larger pieces of wood - but the machine also gets heavier, bulkier, and pricier.

Slide compound mitre saws can do everything a compound mitre saw can do, and more.
Slide compound mitre saws can do everything a compound mitre saw can do, and more.

A 254mm blade size is a good compromise between size and weight/portability, cutting capacity, and price.

You could pay a lot of money for one of these saws. Some of the professional "brand name" models are over $1000. That's fine if you're using them everyday. But for DIY use we think it's more than you need to spend.

A good saw will perform a cut quickly - if the carriage movement is smooth, and the saw blade is effective. The sliding action should be firm but not stiff. A twin-rail (rather than single-rail) system is likely to be smoother and more stable.

When doing a compound mitre cut, the surface finish should look smooth, and there shouldn't be much "tear-out" at the edges.

Ease of use
Look for a model with good stability, controls that are easy to use, a well-positioned thumb-operated guard interlock, and an effective clamp system for securing the work piece during cutting. Before buying a model, try out the grip, to make sure they suit your hand size/shape, and posture.

Most slide compound saws are semi-portable. They may be a little ungainly to handle, but should be light enough to be transported in the car boot and set up on a workbench at another site.

Laser guides
Some models are equipped with laser cut guides, which shine a very thin red line of light onto the work piece being cut. A single laser illuminates one side of the saw cut. A double laser illuminates both sides.

Lock-off button
This is a handy safety feature. The lock-off button must be depressed with the trigger to start the saw motor.

Depress interlock
This is a lever that must be pressed before the saw can be lowered onto the work piece.

End stop
This is an adjustable stop that allows multiple pieces of timber to be cut to the same length. It's useful for lengths up to about 300mm.

Cut-depth stop system
If you want to make rebating or trenching cuts (partway through an object), this feature is useful, as it prevents the blade from cutting too deep. Several models have a cut-depth adjustment (also called a "blade stop" system), but it doesn't always work properly. If the adjustment piece bends, the setting becomes inaccurate.

What they can and can't do

Slide compound mitre saws are very useful for cutting pre-sized timber to length. They can be used to cut house framing-sized timber or finishing mouldings. They can cut at right angles and perform single and double mitre cuts. The sliding mechanism means they are able to cut wider pieces of timber than the simpler drop saws.

The maximum timber-size the saws can handle varies slightly. Most can perform a right-angle cut on a piece of 250mm x 50mm timber. The cutting capacity is less for mitre and compound mitre cuts.

There are a couple of things they can't do - ripping, and cutting panel material such as plywood or MDF. For ripping (cutting timber along its length) you need a portable circular saw, a table saw, or a radial arm saw. For cutting panelling you need a portable circular saw, a jigsaw, or a reciprocating saw.