This stair tread jig is used to ensure that the treads on your stairs are level and square. It will help you build a beautiful finished staircase without having to worry about whether or not it’s going to be straight and level.
The stair tread jig is the simplest and most efficient way to cut top, bottom, and inner bullnoses. You also can use it with our Extra-Long Straight Edge to cut an entire stairway. By holding your workpiece at a fixed distance from the saw blade while you rip or crosscut, it ensures accurate repeat cuts every time. The only thing you need to do is set up your measurements on the dials and cut away.
This stair tread jig allows you to make perfectly level, tapered and gap-free stair stringers in a fraction of the time and with far less waste.
There are quite a few ways to cut stair treads, and most of them are complicated. There’s one method that many carpenters use, however, that makes tread cutting go quickly and accurately. The jig simply locks onto the front edge of a piece of material, allowing you to rout all the treads at once. This can save hours when working on stairs with multiple treads. You can make this handy tool in just a few hours, and it will prove its worth over and over again on your next stairway project.
Make The A-Frame Stair Tread Jig
In this section, we’ll show you how to build a stair tread jig. A stair tread jig is a device that allows you to cut stair treads with perfect 90 degree angles and uniform lengths.
The first thing you’ll need is a 2×4 (8 ft) and a 4×4 (6 ft). Cut the 2×4 so that it forms an “A” shape, approximately 5 inches wide at the base of each leg and 11 inches tall on each side of the “A”.
Next, cut your 4×4 into two pieces: one piece that measures 3 feet long, another piece that measures 6 feet long. Attach these two pieces together so that they form an H-shape: The bottom piece should be perpendicular with respect to the top piece; it should also be placed underneath it so that both ends rest on top of your workbench or table saw bench extension. You can use wood screws or nails for this step if necessary; however if using screws make sure not too over tighten them because they may split out during milling time (especially if working with hardwood).
Make A Test Cut
First, cut a piece of scrap wood to use as a test cut. Make sure to test fit the router bit in your jig and adjust its height so that it cuts the wood cleanly. You want the bit to sit at an angle with the top of your scrap piece, so make sure you can see some of its edge when looking down at it from above.
Clamp The Jig To The Workpiece
Once you’ve marked the treads, clamp the jig to your workpiece. Make sure the jig is firmly clamped in place and that it’s positioned at a distance from one edge of your workpiece equal to the thickness of each individual tread (this will vary depending on what type of wood you use).
Next, use a router with a bearing pilot bit set at an appropriate depth for cutting each individual stair tread (matching its thickness), being careful not to cut too deep into your material. Set the height according to how thick each individual stair tread needs to be when installed—if you accidentally go too deep into your material with this step, use sandpaper or another tool to flatten out any mistakes before moving on.
Use A Router Bit With A Bearing Pilot To Cut The Treads
To cut the treads, you need a router bit with a bearing pilot. A bearing pilot allows you to make straight cuts easily with your hand held router. You can use a router table if you have one, but it’s not necessary because you can simply put the wood on your workbench and hold it down while cutting.
If you don’t already have an appropriately sized base plate for your router, consider purchasing one that will fit both your router bit and the piece of material you’re using as a jig. The larger these components are, the better control over precision you’ll have when building stairs.
Cut The First Riser
Cut the first riser
Fit the router bit to the jig
Use a router bit with a bearing pilot. Place the jig on your workpiece and cut away.
Get A Good Fit On All The Risers
To ensure that your treads are all the same length, thickness and width, you’ll need to make sure your jig can hold both a riser and a tread. This can be accomplished by using two separate clamps on each side of the jig.
If you’re using thicker plywood, such as 3/4″, it might be necessary to use longer screws to reach through both pieces of wood. This is because there’s more material between them than if you were working with thinner plywood, like 1/2″.
Also note that when working with different thicknesses of plywood, you might have trouble positioning them so they line up perfectly in relation to each other when clamping down one piece over another. In this case it’s best not too focus too much on getting it perfect since any small misalignment will disappear once you apply finish or stain around all four sides of each piece
It only takes a few hours to make this jig, but the time savings is considerable.
This jig is quick to make, easy to use and accurate. The time savings is considerable.
You’ll be able to build stairs that are perfectly straight in about an hour or two.
Final words
The beauty of this jig is its simplicity. It relies on gravity and a solid base to keep it in place. This is a good thing because it eliminates the need for complicated alignments that are prone to error. You’ll be able to make hundreds, if not thousands, of cuts with incredible precision using this jig.
