Reasons Why Your Miter Saw Is Not Cutting Straight

It is not uncommon for a miter saw to cut crooked.  However, this may be very frustrating especially if you need to use a miter saw to work on a project.

Most woodworkers face situations where corners of the wood won’t square because the bevel cut didn’t come out as perfect as it should be. This sign can slow down any woodworker; hence, the need to find reasons why your miter saw is not cutting straight is important.to be able to continue with your project smoothly.

The primary reason why a miter saw might not cut straight is an inability to clamp the material down. The machine is designed to pull the material towards the blade during each cut, and if there’s a malfunction in this process, it might result in inaccurate cuts.

Reasons Why Your Miter Saw Is Not Cutting Straight

Damaged Miter Saw Blade

Damaged blades are one of the most common causes of a miter saw cutting crooked. It’s important to sharpen your blade regularly and replace it when you notice that it has become dull.

The blade must have a uniform thickness in order for it to cut straight. You may also notice that your “miter” or “bevel” gauge is crooked, the fence isn’t perpendicular to the blade, or that the blade guard isn’t properly adjusted.

The blade is a vital part of a miter saw. It flies around at such an incredible speed that a little shift can cause damage.

This means that improper installation or any damage can give you issues in your cutting.

Therefore, the blade is the first thing that you should check when you are looking to troubleshoot a miter saw.

Unstable Fence

Another issue that may result in inaccurate cuts is the unstable miter saw fence. It is because the fence must be perfectly perpendicular to the saw blade and leveled in order for it to cut straight.

Due to manufacturing flaws, sometimes even a level fence can look slanted or crooked.

Although often overlooked during routine maintenance, the fence is an essential part of the miter saw.

The fence serves the purpose of holding the material square while the blade does its job. Most times, it’s difficult to tell when the fence gets out of line because of its position.

But it’s important to know that a minor issue in this part can mess your cuts up. Therefore, the fence is the second place to look at when troubleshooting your saw’s inability to cut straight.

Miter Gauge Malfunction

Miter gauges are usually calibrated at the factory, but they can easily get misaligned if not taken care of properly. If you’re noticing that your cuts are still crooked even after all of these steps, your miter gauge could be misaligned or damaged.

Experimentation with adjustments on alignment can help you identify the issue and fix it quickly.

The saw blade is straight and perpendicular to the work surface or face of the saw table. The fence also must be set so that it is perpendicular to the blade. It is important for the fence to be absolutely perpendicular in order for accurate cuts to take place.

While checking, you need to ensure that the gauges are positioned rightly. Yes, there are several presets on the indicator that shows exactly where the saw needs to be set.

However, this can sometimes get shifted, forcing the miter saw not to cut straight. It’s, therefore, crucial for everything to square up at the proper angles.

Broken Bevel Gauge

A faulty bevel gauge can also lead to inaccurate cuts on a miter saw. The bevel gauge is what determines the miter angle the table should be cut at for our project. It’s a metal bar that is fixed to the table or fence and is angled in such a way that it will indicate the correct cutting angle of the blade.

Depending upon its accuracy, it must also be positioned precisely perpendicular to the blade every time you make a cut. A broken bevel gauge can often go undetected until problems start occurring with incorrect cuts being made on your work pieces of wood.

Bevel gauge malfunction is actually one of the most critical parts to check first.Just like the miter gauge, you should look and ensure that the angles are correctly set or are positioned rightly

Don’t just assume that the manufacturer got it perfectly. Even if they do, you don’t expect it to stay the same forever.

Fixing Miter Saw Problems

Once you are sure about the problem, fixing it becomes easier. If, after the troubleshooting steps, however, you still can’t find the issue with your miter saw, then it’s probably a minor issue that your technician can fix.

On the other hand, it could be because you are not handling the miter saw correctly. After all, every experienced woodworker understands that it takes so much skill to use the miter saw.

Lastly, you’ll need to know the degree of error that appears on your cuts. It is at this point that your miter saw needs urgent checks.

Although designed to be accurate, it’s important to note that miter saws are not accurate. Miter saws come with rugged designs.

It is these designs that make for great cuts, giving you great results for every cut. If you do not want any error and it seems your miter saw isn’t doing it rightly, you should consider changing tools.

Tips to improve cuts

Make cuts at full speed

Only make your cuts when the blade is at full speed. This is, in fact, the first answer to your problem. Don’t just start cutting immediately the saw gets turned on. Let the blade be at full speed before you make any contact with the wood. 

The few seconds that you’ll give your saw to get up to speed helps to ensure that the blade makes its way through the material.

Do not rush the blade

The next thing is to ensure that you are not rushing the blade. Once the blade picks up to speed, you’ll need to let the blade do the work firmly, but that doesn’t mean that you should rush it.

Gently but steadily, let the blade make its way through the material. By rushing the blade, you are setting it up to wear out.

Use a clamp

Lastly, there’s a need for you to use a clamp. Bevel cuts are known for slight issues. The primary cause behind this is the positioning of the saw.

Once you’ve put the saw into position for cutting, the blade would naturally want to pull the material towards it while making the cut. Without clamping the material down, you’ll find the material moving mid-cut, hence making the cut inaccurate.

How to make a miter saw cut accurately?

Step 1: Test Stock

Get two boards ready. You need one perfectly straight edge on each board. The best way to ensure that is by jointing the edge. 

The wider the boards, the better. Your test will be more accurate if you cut boards that are close to the maximum width your saw will cut.

Step 2: Make a Cut

With the jointed edges against the fence make a cut. It’s okay to cut both boards at the same time. 

But get in the habit of helping the saw make a good cut. It’s best if you set up the cut so that the blade has material on both sides, rather than just skinning the end grain. 

If you merely skin the end grain the blade can deflect away from it, adversely affecting the cut. If there’s material on both sides of the blade you won’t get deflection, and the cut will be straighter.

Step 3: Check the Cut

Place the jointed edges on a flat surface and position the cut ends against each other. Check for gaps. These boards show a gap at the top of the cut, so the saw can’t be cut at 90-degrees. 

Since both boards were cut the gap amplifies the error. The size of the gap is twice the amount your saw is off. 

You’re done when the cut edges touch uniformly across the width of the board.

Step 4: Check the Bevel

If you have a compound miter saw you also need to make sure the saw cuts a perfect 90-degrees perpendicular to the table. With jointed edges down on the table cut two boards.

Again use material that’s close the max your saw will cut. Check the cut ends the same way you did on the previous step, and adjust the bevel angle until it’s perfect.

With jointed edges against the fence and the saw set to 45-degrees, cut through two boards.

Check the angle

Hold the miter closed and position a square in the inside corner. If the edges of the square are in full contact with the material, you’re good to go. If you see gaps, you need to correct the angle of the cut.

Make a line-of-cut fence

Make it easier to accurately position your material on the saw by adding a line-of-cut fence. This consists of a sacrificial fence you fasten to the miter saw fence.

There are typically holes in the saw fence you can run screws through, into your sacrificial fence. 

The ruler between the sacrificial fence and the saw table provides a small gap under the fence that gives sawdust a place to go so it doesn’t build up in the corner.

After the fence is screwed on, cut through it.

Using the line-of-cut

You’ve now made it very easy to accurately position material on the saw.

Mark your material with a lay out line that’s near the edge, and position the line on the kerf you created in the fence. The edge of the kerf precisely indicates the line of cut of the saw blade.

Frequently Asked Questions

What is a miter saw good for?

A miter saw is designed to make an angled cut for moulding, trim work, rafters and other general carpentry applications. 

The saw also makes straight cross cuts and, when equipped with the right blade, the versatility of a miter saw is an important part of a tool arsenal for professional carpenters as well as DIYers.

Does a miter saw have to be bolted down?

Most tool manufacturers recommend that you bolt down or clamp down your miter saw, and for good reason. 

When kickback happens, the saw can shift while the blade is spinning, which can be extremely dangerous. 

Conclusion

It’s important to take care of your tools so that they work well for you. Whether it’s a saw blade, fence, or bevel gauge, if something isn’t working properly, then you need to fix it as soon as possible.

Without a functioning piece of equipment, there will be no way to get accurate results when cutting wood and other materials. It can also lead to some serious safety issues which should never happen in any situation where people are around power tools like these.

There are no perfect miters, so if your miter saw has a problem, contact the company that made it. They will fix it quickly and easily.

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