The 5-Cut Method Made Easy! a Foolproof Process and Calculator for Square Table Saw Crosscut Sled Fences

The 5-Cut Method for squaring table saw crosscut sled fences is the most common method for making your fence very square to the table saw blade. In fact, it can get as close as one thousandth of an inch (0.001") of accuracy.

The problem is, it's not the easiest process to follow.

I spent a few hours learning everything I could about the 5-cut method and made this simple and foolproof calculator to make the process so much easier.

Supplies

Tools:

1. A table saw crosscut sled fence
2. A set of feeler gauges
3. A measuring caliper (optional, but highly recommended)
4. Clamps
5. Drill
6. Screws
7. 5-Cut calculator

Step 1: Assemble Your Table Saw Sled Base

The first thing we’ll need is a table saw sled. This process is pretty easy, and I have another Instructable on assembling a table saw sled. As far as size goes, make it whatever size you like. Mine is 20 inches deep and 24 inches wide so I can cross-cut 18"-deep cabinet parts.

I now use UHMW runners instead of wood because they're more stable throughout the seasons. I can drill through the plastic and attach them with screws as I would with wooden runners.

When the runners are installed, I cut a groove halfway through the base so I can use it as a guide for the next step.

Step 2: Attach the Front Fence

Attaching the front fence (the one farthest from you when it's on the table saw) can be done by eye with a trusted square. This fence doesn’t have to be that accurate because its main purpose is to hold the sled together.

First I drive a single screw into one end of the fence, then use a square to align it with the blade groove that I've cut halfway through the base. Clamp, drill, and drive another screw to secure it.

I went ahead and added a couple more screws for rigidity, but you don't have to. If you do add them, just be sure you don't drive a screw close to the blade — think about whether you'll use this with the blade at an angle, or if you'll use it with a dado set. If a blade contacts a screw during operation, it's going to be a bad day.

Step 3: Temporarily Attach the Rear Fence

The process begins identically to that of the front fence: sink one screw into the fence, then align with a trusted square. Clamp, drill, and drive another screw into the opposite end of the fence.

Pro-tip: Choose a side that will be your 'pivot screw' now. This screw will not be removed from the sled. Sometimes it helps to sink the pivot screw a set distance from the edge of the sled — for example, 0.75" or 1" away — so you can measure from that edge over to the other side when we make our correction in the future.

With the rear fence secured with two screws, complete the blade kerf all the way through the sled. The fences will keep the two halves of the base attached.

Step 4: Get Your First 5-cut Method Reading

To get the first five cut reading, begin with a rectangle of material like plywood or MDF around 12" x 6" (the exact size isn't perfect).

Cut #1

While holding one relatively straight side against the rear fence, make a cut so that just the very edge of the material is fully cut away. You don't want to leave any portion uncut, so if you need to make a second cut, do so now.

Cuts #2, 3, 4

Rotate the material so the freshly cut edge is against the rear fence, then make another cut just like the first so that the whole edge is taken away by the blade. Repeat this for cuts 3 and 4, rotating so that the freshly cut edge is against the rear fence each time.

At this point, all four sides should have a freshly cut edge.

Cut #5

For this final cut, scoot the material toward the blade so that about an inch will be sliced off the end. The exact width of this cut isn’t really important, but it is critical that you mark which side is which.

Before cutting, label the end farthest away from you as 'A', and the end closest to you as 'B'. Then make the cut. This little slice will be what we measure squareness from.

Get your slice's measurements

Use a measuring caliper to measure the width of each end, and the total length of the slice.

Step 5: Plug Measurements Into the Simple 5-cut Calculator Tool

Now you can plug the measurements you got earlier into the simple 5-cut method calculator that I created to help me get perfect results every time. It's phone-friendly and web-based using a tool called Coda, so you can use it while you're in the shop.

I built the calculator because even though I've performed the 5-cut method quite a few times, I still tend to mix up the direction I need to pivot the fence to correct the angle. Most other materials out there fail to tell you that the side that your pivot screw is on will change the direction of the pivot. My calculator now asks you to select a pivot side so you get the right answer every time.

Just plug in the four measurements, confirm you pivot side, and get a very clear answer in return.

Step 6: Adjust the Fence

The calculator will either tell you to pivot your fence forward toward the blade, or backward away from it. Mine needed to go forward, so that's what the photos will show.

For this step, you'll need your feeler gauges, a couple of clamps, and a block that is shaped to a dull point. This shape will help you get an accurate correction.

First, make a mark at the correction distance that you entered in step 4 in the calculator. Remember, this is the distance from the pivot screw, not the edge of the sled, to that point.

Pivoting the fence toward the blade

1. Get a combination of feeler gauges equal to the correction amount that the calculator gave you.
2. Place the feeler gauges against the fence at the correction point (this is the distance from the pivot screw you identified in step 5)
3. Place the pointed block firmly against the feeler gauges and clamp the block down.
4. Remove the screw closest to the correction (your non-pivot screw)
5. Remove the feeler gauges.
6. Gently push the fence toward the pointed end of the block.
7. Clamp the fence down.
8. Drill and drive a screw into a new hole in the fence to secure it.

Pivoting the fence away from the blade.

1. Put together a combination of feeler gauges equal to the correction amount that the calculator gave you.
2. Place the pointed block firmly against the fence and clamp the block down.
3. Remove the non-pivot screw securing the fence, which will allow it to pivot.
4. Pull the fence backward, then insert the feeler gauges between the block and the fence.
5. Gently push the fence toward the pointed block to capture the feeler gauges between.
6. Clamp the fence down.
7. Drill and drive a screw into a new hole in the fence to secure it.

Step 7: Repeat the 5-Cut Method

Repeat steps 4 and 5 again. If the calculator returns a correction amount under one thousandth of an inch, your crosscut sled is as perpendicular as can be to your table saw blade.

Go out there and make some sawdust!