Why Does My Table Saw Not Cut Straight – 5 important reasons

You need to make a cut with your table saw that really matters for your project to succeed. After making that cut, you find that there is a minimal misalignment on your table saw that is causing your workpieces to not line up properly. So you are wondering, why does my table saw not cut straight, and how can I solve this problem quickly?

There can be several reasons why your table saw is not cutting straight lines. Either it’s a human error because you’re inexperienced and using poor form, or it’s mechanical issues like a misaligned or warped blade, or the fence isn’t parallel to the miter slots.

Table saws can deal with multiple issues, as you can see in this table saw troubleshooting list.
Fortunately, your table saw not cutting straight lines is not a big problem, and small adjustments can give a completely different result. You just need to know what to look for and what steps to take to get your table saw cutting straight lines. That is what you will be able to discover in this article.

Why Is Cutting Straight Lines with a Table Saw So Important

There are two main reasons why your table saw should make cuts as straight as possible.
A first reason is that you can always make right-angled cuts so that your parts fit together perfectly. An opening anywhere where two pieces of wood meet will seriously detract from the overall look of your project and make it look a lot inferior.

A second important reason for cutting straight lines is the safety aspect. Wood must be able to run along the saw blade with as little friction as possible. Friction can cause heat, which is one of the reasons why you can get burn marks on wood from a table saw. (Also read the related article, Why Is My Table Saw Burning Wood? (9 Reasons + Easy Fix))

In addition to burn marks, when the friction is so great, there can be a danger that kickback occurs and you sustain injuries. More on this later in this article.

Why Does My Table Saw Not Cut Straight? 5 Reasons

A table saw is one of the most important tools in the workshop and you want to cut it as straight as possible. This section will explain the various causes of your table saw not cutting straight lines. You’ll also find solutions to all of your table saw problems, allowing you to solve them quickly.

I’d like to emphasize that the type of table saw you have will determine the method of correction you use. Every make and model is distinct. As a result, for each issue, there is a general explanation of how to correct each mentioned error.

The Blade Is Misaligned

Keeping the blade in line is an important aspect of using a table saw. Keep your miter slot parallel to the blade and the fence at all times. To fix or check this, all you need is a framing square.

The Blade Is Not Perpendicular To The Table.

The blade that is not perpendicular to the table will not immediately prevent your table saw from cutting straight lines, but it is important to be able to position the blade perpendicular so that you have a good base to make other corrections.

When aligning your blade, raise it halfway above the table to ensure proper angle. Place the framing square perpendicular to the table saw’s surface. One side should be up against the blade and the other against the table. Make sure there is no space between the court and the blade as the square sits flat on the table.

By adjusting the tilting apparatus beneath the table, you can return the blade to 90 degrees. Check the angle markings and set the angle to 0 degrees. Then, tighten the blade so that it is perpendicular to the table. Make sure you use a carpenter square to get the right angle.

The Blade Is Not Aligned With The Miter Slot

When you start cutting wood, if the blade is not parallel with the miter slots, you will have problems. As a result, the squareness of your workpiece will be incorrect, affecting the construction of your project. You will notice this as it is hard to push wood through the table saw.

A combination square can be used to check the parallelism of your blade, but a dial indicator is recommended if you want to be very precise (like the one you can find below). To get started, you’ll also need a highlighter.

To see if the blade is parallel to the miter slots, do the following: Insert the dial indicator into the miter slot and measure the distance to the blade’s front edge. Rotate the dial indicator’s rotating ring until the zero mark reaches the needle. With the marker, mark the location where you measured.

Now slide the dial indicator further back at the height of the back of the blade. Turn the blade manually until the mark is opposite the dial indicator. If the needle of the dial indicator is back to zero, you don’t have to do anything.

If not, you have to look under the table saw blade for the screws that hold the saw blade in place and loosen them. Once these are loose, you have to move the saw blade and take another measurement. Keep repeating this until the blade is completely parallel, then you can retighten the screws.

Warped Table Saw Blade

With your table saw you will cut a wide variety of types of wood. Some woods are soft, others are hard. This is expressed in janka rating.
You also have coarse cuts and fine cuts to make. If you don’t have the right saw blade for the type of wood and job, you can end up with a bent saw blade. So it is good to know how this problem can form.

After cutting relatively hard material, your table saw blade may have a curved edge. Also, the blade can lose some of the so-called teeth, especially if you don’t use a good blade. This will result in the table saw not cutting straight.

When cutting it is important to ensure that the wood is pressed against the fence and lies flat on the table. As important as that is, if you’re careless and ram the wood too hard, you can eventually bend it from how you push the wood through the blade.

By pushing the wood in at the wrong angle, or too hard, friction will develop heat, which will eventually cause the blade to warp. If you’re getting warped blades but have no idea what’s causing it, this could probably be the reason for the table saw not cutting straight.

As soon as you discover that a blade is warped, you need to remove it. A warped blade will not only ruin your projects, but can cause a kickback and potentially harm you.
Related article: Understanding Table Saw Blades | Always Find The Perfect One

Loose Blade Holding Nut

The table saw blade is held in place on the arbor by a nut. This lock can be just right, too loose, or too tight. Overtightening a nut increases the likelihood that your saw blade will stop turning and cutting.

This is one of the most common causes of a saw stopping halfway through a cut. To be clear, an overtightened saw blade nut is not the primary cause of an uneven cut; rather, it is an under tightened nut.

While cutting, a loosened nut can cause a vibrating edge. A perfectly straight cut is impossible to achieve with a vibrating table saw blade.

If a fastening nut is not properly tightened, it will loosen after a long period of rotation. This is a common occurrence, and it is one of the reasons why regular maintenance is essential in your woodworking shop.

This problem is easily solved by doing the following: Begin by removing the plug from the socket.

Lift the insert plate off the table by wrapping it around the blade. It’s the part where the saw blade appears. Unless you have easy access from the bottom, this will make it much easier to get to the nut.
Make sure the blade is not rotating.

Some saws have a lock that prevents the blade from moving as you tighten or loosen it. If yours doesn’t, you’ll need to place a screwdriver or something else on the table beneath the blade’s teeth to keep it from spinning as you tighten the nut.

Once locked, use the key that came with your saw to get started. Tighten the nut above the blade with your wrench, making sure it is in the proper position. If it has shifted slightly, reposition it before tightening it.
Make sure not to overtighten the nut.

Misaligned Fence

The fence on a table saw is one of the most important accessories that will help you cutting straight lines. If you’ve already inspected the blade and all previous causes, and it’s still difficult to cut a flawless straight line with your saw, the problem may be with the fence.

A misaligned fence will not only cause an uneven cut but can also cause kickback. If the fence is not perfectly parallel to the blade, it puts pressure on the back of the blade, which grabs the wood and flings it around the workshop, injuring yourself or anyone else in your workshop! This is one of the reasons your table saw blade can start binding.

To avoid dangerous kickback from the saw, make sure to align the fence with the miter slot of your table saw or the front and back of the blade. It is always best to check two reference points.

Follow the steps below to resolve the misaligned fence issue.

Slide the fence into the slot and then lock one end of it.
Then carefully position the other end so that your fence remains 180 degrees from the blade tip.
Measure from the miter slot or blade at two locations front and back to make sure they are the same distance.

Unfortunately, rip fences get a little slack over time and may not tighten properly, allowing them to move even if you think you’ve secured them. If this starts to happen, you wil notice that is is hard to push wood through the table saw, so it’s time to see if you can find a new fence.

To know on what side of the blade you need to place the fence, I suggest you should read my article What Side of the Table Saw Should the Fence Be on – a Clear Answer

Handling The Wood Traffic The Wrong Way

You would be surprised at the great consequences it has when you handle the wood traffic the wrong way when sawing. When pushing wood through a table saw blade, there are a few things to keep in mind that will not only give you a nicer cut, but also protect you, as the wood is less likely to kick back and cause damage to you.

Keep the wood flat on the table. It’s easy not to realize you’re lifting the front of the wood and holding it off the table. Or you may be pushing the wood down and the back will come up when it touches the blade. This can make your cuts look like crap.

Do your best to keep the wood flat on the tabletop. Use a push stick to keep your hands safe and to guide the wood through the blade.
In addition, also keep the wood pushed flat against the side of the fence. It is easy to float the wood and pull it away from the fence. Always make sure to press the wood against the fence as you push it through the blade in order for cutting straight lines.

As simple as these two points seem, it takes practice to get used to how it should feel when you cut wood on a table saw. If you are new to the hobby, I recommend using feather boards.