What is a flush trim saw?

A flush trim saw, also known as a oscillating saw or multi-tool saw, is a specialized handheld saw used for detailed woodworking and remodeling projects. It is designed to “flush cut” materials by cutting very close to flat surfaces, allowing you to trim materials so they are perfectly flush with other surfaces. Flush trim saws have a thin, narrow blade that can fit into tight spaces and produce clean, accurate cuts.

What is a Flush Trim Saw Used For?

Flush trim saws have many uses in woodworking, construction, and home remodeling. Here are some of the most common uses and applications:

• Trimming protruding dowels or tenons – The thin blade can trim wood protrusions flush to the surface.
• Cutting flush with cabinets, floors, or walls – Useful for installing cabinets, floors, and moldings tightly against existing surfaces.
• Detail and finish carpentry – Allows for tight, precision cuts needed for detail work.
• Cutting openings in walls and floors – Can cut openings for electrical boxes, plumbing, and HVAC systems.
• Removing old caulk and adhesives – The oscillating motion can scrape away old caulk and adhesives.
• Installing door hinges – Allows you to recess hinges into doors and door jambs.

The thin profile of a flush trim saw’s blade gives it the unique ability to get into tight spaces and make cuts with minimal clearance. This makes it an indispensable tool for detailed trim work, renovations, and finishing tasks.

Flush Trim Saw Blades

The most important part of a flush trim saw is the specialized blade. Here are key characteristics of flush trim saw blades:

• Very thin blade – Typically around 1/16″ thick at the teeth. This allows the blade to fit into tight spaces.
• Narrow width – Standard blades are around 1-1/4″ to 1-1/2″ wide. Makes tight turns possible.
• Fine tooth pattern – Teeth are very small and closely spaced, which provides a smooth cut.
• Cuts on the pull stroke – Most flush trim saws cut when pulling the blade toward you.
• Limited set on teeth – Minimal offset of the teeth allows the blade to cut “flush” with surfaces.

The most common blade materials used are carbon steel and carbide grit. Carbon steel provides good edge retention and flexibility. Carbide grit blades last longer than steel when cutting masonry and tile.

How Does a Flush Trim Saw Work?

Flush trim saws have an entirely different cutting action compared to normal handsaws and power saws. Here is how they work:

• The motor rapidly oscillates (moves back and forth) the saw blade.
• This oscillating movement allows the teeth to cut efficiently on both the push and pull stroke.
• Blade oscillations are very small and rapid, around 15,000 to 20,000 oscillations per minute.
• Gives the effect of a tiny saw blade moving in and out very quickly along the cutting path.
• Produces a very smooth cut due to the high frequency of the cutting motion.

This rapid oscillation motion is the key to flush trim saws’ versatility and ability to make intricate cuts. It allows them to cut flush in situations where a normal saw blade would not fit or would bind up.

Cordless Flush Trim Saws

Flush trim saws were originally small handheld tools powered by an AC cord plugged into a wall outlet. However, advanced lithium-ion batteries have enabled cordless flush trim saws that offer the freedom to work anywhere:

• Cordless convenience – No cord to drag around or limit your working area.
• Compact size – Same small size but without a bulky cord.
• Easy control – Well balanced for using one-handed in tight spots.
• Quick cuts – Powerful motors cut through most materials quickly.
• Long run time – Lithium-ion batteries often provide 60+ minutes of run time per charge.

Cordless flush trim saws provide the ultimate in convenience and mobility. Many pros choose cordless models as their primary flush trim saw for work around the house or at job sites.

Types of Flush Trim Saw Blades

Flush trim saws use several types of interchangeable blades tailored to different materials and cutting tasks:

Woodcutting Blades

• Designed to cut wood, plywood, OSB, and other wood materials.
• Typically carbon steel blades with about 24 teeth per inch.
• Teeth have a minimal set and sharp points to slice wood cleanly.
• Come in widths from 1″ to 2″ for standard flush cutting or extended reach.

Laminate Blades

• Specialized for cutting wood laminates and veneers.
• Very fine teeth, around 60 teeth per inch.
• Cuts laminate without tearing or splintering the surface.

Metal Cutting Blades

• Designed for cutting soft metals like aluminum and copper.
• Carbide grit blade coating helps resist wear when cutting metal.
• Typically have around 10 teeth per inch.

Masonry Blades

• For cutting concrete, brick, tile, and other masonry.
• Diamond grit or carbide grit coating to abrade and cut masonry.
• Should use a dust collection system when cutting masonry to reduce dust.

Choosing the right blade for the material you need to cut will produce the best results and blade life.

Using a Flush Trim Saw Safely

While very handy tools, flush trim saws can be dangerous if not used properly. Follow these tips for safe operation:

• Always read and follow the manufacturer’s safety instructions.
• Wear eye protection to shield your eyes from debris.
• Use work gloves to protect your hands from sharp edges.
• Avoid awkward hand positions that make blade control difficult.
• Hold workpiece securely in a vise or clamps if possible.
• Keep your free hand well clear of the blade.
• Don’t force the saw if it starts to bind in a cut.
• Maintain good footing and avoid cutting with the saw above shoulder height.
• Unplug saw when changing blades or during maintenance.

With careful handling and correct techniques, flush trim saws can make many home improvement tasks much easier. But always respect the exposed blade and potential for serious cuts or injuries if used carelessly.

Common Brands of Flush Trim Saws

Many major power tool companies produce flush trim saws. Here are some of the most popular flush trim saw brands:

DeWalt

• Leading brand amongst building trades professionals.
• Offers both corded and cordless flush trim saws.
• Powerful motor with variable speed control.
• Accepts a wide range of blade types.
• Typically used with 20V Max lithium batteries.

Milwaukee

• Another very popular pro brand.
• Cordless M12 and M18 lines with multiple flush trim saw options.
• REDLINK overload protection for long life.
• Cuts many materials besides just wood.
• Uses REDLITHIUM battery packs.

Makita

• Major brand known for advanced lithium-ion cordless tools.
• 18V and 12V max models with tool-less blade changes.
• Variable speed control with soft start.
• Accepts blades from 10mm to 65mm wide.
• Star protection technology prevents overloading.

Bosch

• High performance brand with excellent flush trim saws.
• Corded and cordless variants available.
• Tool-free blade release for quick changes.
• Constant response circuitry maintains speed.
• Designed for low vibration and user comfort.

Rockwell

• Offers a corded 4.0A flush trim saw.
• Compact and lightweight at only 3 lbs.
• Cuts on left or right side for maximum versatility.
• Soft no-slip grip for comfort and control.
• Constant speed control under load.

With all major brands, the key is finding a model that balances power, features, and budget for your needs.

Comparing Flush Trim Saws vs Other Saw Types

What advantages do flush trim saws offer compared to other saws? Here are how they differ from several other saw options:

Flush Trim Saws vs Hack Saws

• Flush Trim Saw Advantages:
• Much thinner blade fits into tight spaces.
• Oscillating blade allows flush cutting capability.
• Cordless models offer more convenient use.
• Typically easier control for accurate cuts.
• Hack Saw Advantages:
• Less expensive blades.
• Can cut thicker/harder material if needed.
• Simple frame accepts standard replaceable blades.

Flush Trim Saws vs Coping Saws

• Flush Trim Saw Advantages:
• Easier to control straight cuts.
• Cuts faster with powered oscillating action.
• Easier to apply steady pressure when cutting.
• Cutoffs can be reused more easily.
• Coping Saw Advantages:
• Better for cutting complex curved shapes.
• Blades are very inexpensive.
• Can cut very tight radius curves.
• Less waste since kerf width is thinner.

Flush Trim Saws vs Jigsaws

• Flush Trim Saw Advantages:
• Thinner blade allows flush cutting capability.
• Small size and control for fine finishing cuts.
• Easier to guide precisely by hand.
• Creates less surface splintering.
• Jigsaw Advantages:
• Cuts larger/thicker materials easily.
• Bevel cuts possible on most jigsaws.
• Lower cost blades overall.
• Built-in dust blower keeps cutline visible.

The main advantage of a flush trim saw is the thin, oscillating blade that can make precision flush cuts other saw types simply cannot. But for thicker materials or long cuts, a jigsaw or hack saw is generally faster and more practical.

Buying Guide for Flush Trim Saws

Ready to buy a flush trim saw? Keep these tips in mind when choosing one:

• Consider how you will use it – Trimming cabinet installs? Fine woodworking? Remodeling projects?
• Corded vs cordless – Corded has unlimited runtime but requires outlet access. Cordless has greater mobility.
• Power level – Look for amps on corded or battery voltage on cordless. More means faster cutting.
• Variable speed control – Allows matching blade speed to workpiece and improves cutting.
• Blade changing method – Tool-less blade changes make swapping blades faster.
• Blade compatibility – Ensure the saw accepts the blade types you need.
• Hand fit – Try holding the saw to ensure good grip and balance.
• Cost – Flush trim saws range from about $50 to $200 or more.

Take your time selecting the right flush trim saw model for your needs and budget. A quality saw used properly will last for years of home improvement projects.

Conclusion

Flush trim saws are a must-have tool for any detailed woodworking, carpentry, or remodeling work. Compared to normal saw blades, the thin profile and rapid oscillating action allow flush trim saws to cut right next to existing surfaces for a perfect fit. While especially handy for trim and finish work, the versatility of flush trim saws makes them useful for many cutting applications where a standard saw just won’t fit. Whether you choose a cordless or corded model, a good flush trim saw will prove itself invaluable anytime precision cutting is needed.