How to Make Miter & Bevel Cuts

 

How to Make Miter & Bevel Cuts

 

How to Make Perfect Miter & Bevel Cuts may be a little tricky if you have never done this before, so make sure that you fully understand these instructions before cutting any boards that you are using for a project.

It will be best to practice a few cuts on some scrap lumber before making actual cuts for your project.

Tools & Materials Needed:

  • Safety Glasses
  • Work Gloves (preferably Mechanic’s Gloves)
  • Sharpened Pencil
  • 12″ Combination Square or Speed Square
  • Painter’s Tape
  • Standard Protractor
  • Compound Miter Saw
  • Scrap Lumber (approximately 24” – 48” long. Can be 1” x 2”, 2” x 2”, or 2” x 4”)
  • Whisk Broom
  • Broom & Dust Pan or Shop Vac

Purchase Tools at:   AceHardware.com   Amazon.com   eBay.com   HomeDepot.com   SamsClub.com   Walmart.com

 

_____________________________________________________________________________

 

20170413_195522

 

About Miter Cuts & Compound Miter Saws

Miter Cuts are angled cuts made at 45 degree for the purpose of joining two adjoining pieces nearly seamlessly at a corner. They are commonly used for molding and frames.

Compound miter saws are one of the most versatile power saws, and are the best tools to use when making Miter Cuts. Most are very lightweight and portable, with common blade sizes ranging from 8” – 12”. The 10” size is usually adequate for most Home Projects, and the size that I would recommend.

Some come with laser guides which provide a precise visual indication of where the cut will be made on your workpiece. A safety clamp, which usually come standard with most models, helps to lock your workpiece into position prior to making a cut. This is an especially important feature when cutting smaller workpieces.

Most saws have an adjustable scale plate for table swiveling, with positive stops at commonly used angles. Normally the workpiece is held flat on the table, and table swiveling will produce a Miter Cut (blade vertical and angled across work piece).

 

About Bevel Cuts

Bevel Cuts are cuts that made across the ends of boards, and have angles that conform to the corner to which they will be installed. When cut perfectly, they will nearly seamlessly join two adjoining pieces.

Compound miter saws usually have adjustable stops at 90 and 45 degrees for saw head tilting, allowing easy and very accurate adjustments of the saw. Table swiveling in both directions is universal but most saws allow head tilting only in one direction (counter-clockwise).

Saw head rotation will produce a Bevel Cut (blade angled from vertical and square across work piece).

When used in combination, these will produce a compound cut.

Purchase Compound Miter Saws at:   AceHardware.com   Amazon.com   eBay.com   HomeDepot.com   Walmart.com

 

_____________________________________________________________________________

 

Step-by-Step Instructions

 

Step 1 – Making a Miter Cut

Put on your safety glasses and your work gloves.

As previously stated, making a Miter Cut is made with the saw blade vertical, and angled at 45 degrees across work piece. The head of the saw is positioned at 90 degrees to the work table, or perpendicular to it.

Take your pencil and your 12” square, and pencil a mark, across the face of your scrap lumber, at a 45 degree angle near one of the edges of your board. (If you are using a combination square, you will first make a mark along the 2” long, angled portion of the square, and then continue your mark with the 12” blade portion of the tool, all the way across the face of the board.)

Now, position your board flat against the table, and flat against the fence, with your cutting mark near the area where the saw blade will cut. Position your saw blade at the correct 45 degree angle which mirrors your cutting mark, by loosening the lock-down knob on the saw, swiveling the saw head to the correct 45 degree mark, and locking down your lock-cown knob.

With the saw in the OFF position, and keeping your fingers away from the ON trigger, pull the saw head down, and line up the blade with the right edge of the cut mark on your board. Make sure that your board is firmly against the saw table, as well as the saw fence.

(If you are cutting a board that is less than 8” long, it is strongly recommended that you use your Safety Clamp or an Adjustable Wood Clamp to securely hold your board. You must be able to securely hold your board in place while keeping your fingers at least several inches away from the saw blade while cutting.)

Now, while continuing to hold your board firmly in the proper place, turn your saw on and make your cut, attempting to be as close to your mark as possible without letting the saw blade erase it. Do this as many times as is necessary for you to feel comfortable, and accurate, performing this type of cut.

Then, remark your board at the opposite 45 degree angle, adjust your saw accordingly, and repeat the process for this angle. Now, put the two cut pieces together, and taking your square, check your accuracy. Once you are comfortable with Miter Cuts, proceed to the next Step.

 

Step 2 – Calculating the Correct Angle of a Bevel Cut

Regardless of whether you own an old house or a brand new one, you will be hard pressed to find any two adjoining walls that are exactly at right angles to each other, or a perfect 90 degree. That is why it can be a little challenging when attempting to Bevel trim that fits perfectly for top or baseboard molding.

On top of that, compound miter saws confuse a lot users for one simple reason—they aren’t designed for finish carpentry, such as Beveling trim, they are designed for framing and stairs. That is why most miter saw gauges are set up off 90 degrees to the back of the fence. In fact, some miter saws even include roof pitch angles on the miter saw gauge, which only further confuses the finish carpenter.

When cutting a Bevel for trim, you need to work off 180 degrees, not 90 degrees, and the first thing that you will need to do is measure the angle of your corner. For this, you will need a protractor.

There are many different types of protractors on the market. There are standard protractors, digital protractors, and even protractors that will automatically calculate the exact angle that you need to use on your miter saw to cut your Bevel.

It is my belief, that it is better for the homeowner to understand the process, rather than have a tool complete the calculation for you. If you understand the how and why, it will carry over into other projects, and will benefit you greatly in all of your Home Renovation projects.

Therefore, I recommend that you use a standard protractor, so you will know at a glance the difference between an acute angle and an obtuse angle. That means when you visualize the angle, you will be starting off on the right foot. (An Acute Angle is an angle that is less than 90 degrees. An Obtuse Angle is one which is between 90 degrees and 180 degrees.)

Let me simplify the process for you and put an end to any confusion:

Calculating an Obtuse Angle (between 90 degrees and 180 degrees)

  • Measure the angle with your standard protractor
  • Subtract the reading on the protractor from 180 degrees and bisect the difference (divide in half)
  • That will give you the angle to set your miter saw at

Calculating an Acute Angle (less than 90 degrees)

  • Measure the angle with your standard protractor
  • Subtract the reading on the protractor from 180 degrees and bisect the difference (divide in half)
  • That will give you the angle to set your miter saw at

Problem? You say that your Miter Saw only goes to 45 degrees, but you need an Angle that is more than that?

Problem Solved:  Let’s say you have an angle of 80 degrees. You do the math, and the setting on your miter saw should be at 50 degrees, but your saw only goes to 45 degrees. Well, whenever you cut a Bevel angle, the angle on the opposite piece of wood, will be equal to:  90 degrees minus the Bevel angle cut. So, if you need a 50 degree angle, subtract 50 from 90, and you get 40. The angle on the opposite piece of wood will be a 40 degree angle.

So, if you set your miter saw Bevel angle to 40 degrees, and cut on the other side of your mark line, the remaining board piece will have your 50 degree angle. Simple, right? Whoa, not so fast . . .

You need to flip your board 180 degrees before making the cut, or the angle that you cut will be for an outside corner instead of an Inside one. Therefore, you need to make sure that you mark the correct face of the board. You will need to have your Short-Side face flat against your saw table, and your Long-Side face, facing up (the opposite of the set up for an Obtuse angle). Also, make sure that you are cutting on the correct side of your mark or your board will come up short. Always be aware of the section of the board that you need.

 

Step 3 – Marking & Making the Bevel Cut

I strongly suggest that you make a couple of practice Bevel Cuts using pieces of scrap lumber before actually cutting your trim molding.

Using your standard protractor, measure any corner in your house. Decide on whether your angle is an Obtuse Angle or an Acute Angle, and whether it is an Inside Corner or an Outside Corner. Continue reading this Step, and then follow the specific instructions for that angle. Now, calculate the angle to set your miter saw at.

With your saw Unplugged, loosen the lock-down (If you do not know where your rotation lock-down is, consult the owner’s manual for your saw.), rotate your saw head to the appropriate angle, and tighten the lock-down.

When making Bevel Cuts for Inside Corners,  refer to the face of your board that will be against the wall, as the ‘Long-Side’, and the face of your board that faces outward, or towards you, will be called the ‘Short-Side’. This refers to the measurements made on each of the faces from end to end. For Outside Corners, this will be the opposite.

Remember, your saw head probably only tilts in a counter-clockwise direction. So:

  • Inside Corners with Obtuse Angles and Outside Corners with Acute Angles:

Board position will be:  ‘Short-Side’ up, and the ‘Long-Side’ against the saw table.

  • Outside Corners with Obtuse Angles, and Inside Corners with Acute Angles

Long Side’ up, and the Short Side’ will be flat on the table.

Always make sure that you are cutting on the correct side of your mark, or your board will come up a little short.

 

Mark & Cut an Inside Corner with an Obtuse Angle or an Outside Corners with an Acute Angle

Place a small piece of painter’s tape on one face of your test board to indicate which face will be the ‘Short-Side’. Take your pencil and your protractor (set at the same angle determined for your miter saw), and pencil a mark, across the edge of your board at your cutting end. This mark should run from the edge of your ‘Long-Side’ toward your ‘Short-Side’ face, which will be further away from the edge. Now, flip the board over and repeat this on the other edge of your board, on the same end, making sure that your ‘Short Side’ face is the same.

Always be aware of which face of your board is the ‘Short-Side’ so that you are making your Bevel Cuts correctly. It is best to always use a small piece of painter’s tape to mark your ‘Short-Side’, and remove the tape when your cuts have been completed.)

Then, extend your marks slightly, from the edges of your board to the face of the board. Now, using your T-square, connect the marks. This will be your cut mark.

With the saw in the OFF position, and keeping your fingers away from the ON trigger, pull the saw head down, and line up the blade with the correct edge of the cut mark on your board (keeping in mind the portion of the board that you will be using). Your blade should line up perfectly with the angle of your cut line. If it does not, you will need to go back through the process and find your error.

Make sure that your board is firmly against the saw table, as well as the saw fence, with your fingers, at least several inches away from your saw blade, and your blade guard in place. You are again attempting to be as close to your mark as possible without letting the saw blade erase it.

Using your same guidelines as before, for when to use your safety clamp, and while continuing to hold your board firmly in the proper place, turn your saw on and make your cut. Then repeat this process for the other end of your board. You will need to flip your board end over end (spin it 180 degrees). When finished, you should have Bevels on both ends of your board, with the Short-Sides on the same face of your board. Now, cut your board in half, fit your Bevel Cuts together, and check your test boards for fit on your chosen corner.

Do this as many times as is necessary for you to feel comfortable, and accurate, performing this type of cut.

 

Mark & Cut an Outside Corner with an Obtuse Angle or an Inside Corner with an Acute Angle

Place a small piece of painter’s tape on one face of your test board to indicate which face will be the ‘Long-Side’. Take your pencil and your protractor (set at the same angle determined for your miter saw), and pencil a mark, across the edge of your board at your cutting end. This mark should run from the edge of your ‘Short-Side’ toward your ‘Long-Side’ face, which will be closer to the edge. Now, flip the board over and repeat this on the other edge of your board, on the same end, making sure that your ‘Long Side’ face is the same.

Always be aware of which face of your board is the ‘Long-Side’ so that you are making your Bevel Cuts correctly. It is best to always use a small piece of painter’s tape to mark your ‘Long-Side’, and remove the tape when your cuts have been completed.

Then, extend your marks slightly, from the edges of your board to the face of the board. Now, using your T-square, connect the marks. This will be your cut mark.

With the saw in the OFF position, and keeping your fingers away from the ON trigger, pull the saw head down, and line up the blade with the correct edge of the cut mark on your board (keeping in mind the portion of the board that you will be using). Your blade should line up perfectly with the angle of your cut line. If it does not, you will need to go back through the process and find your error.

Make sure that your board is firmly against the saw table, as well as the saw fence, with your fingers, at least several inches away from your saw blade, and your blade guard in place. You are again attempting to be as close to your mark as possible without letting the saw blade erase it.

Using your same guidelines as before, for when to use your safety clamp, and while continuing to hold your board firmly in the proper place, turn your saw ON and make your cut. Then repeat this process for the other end of your board. You will need to flip your Board end over end (spin it 180 degrees). When finished, you should have Bevels on both ends of your board, with the Long-Sides on the same face of your board. Now, cut your board in half, fit your Bevel Cuts together, and check your test boards for fit on your chosen corner.

Do this as many times as is necessary for you to feel comfortable, and accurate, performing this type of cut.

Repeat the process as many times as needed for both Obtuse Angles and Acute Angles, as well as Inside Corners and Outside Corners, until you feel very comfortable with all processes. When you are finally comfortable, go ahead and cut your trim molding.

 

Congratulations on a Job Well-Done!

 

Please take the time to leave a Comment, letting me know how your project went.

 

Thank you,

CJ Dodaro

Leave a Comment

Your email address will not be published. Required fields are marked *