Shop-Made Router Edge Guide for Cutting Accurate Grooves & Dadoes
A handheld router is one of my favorite tools for cutting grooves and dadoes. With a straight bit and a good edge guide, it's easy to make clean, accurate cuts for cabinet parts, shelves, and other woodworking projects.
But there's one limitation with most standard router edge guides: They don't reach very far from the edge of the workpiece.
That's fine when you're routing a groove near the edge of a board. But when the joint needs to be several inches farther in, a conventional edge guide may not have enough reach.
To solve that problem, I built this simple extended router edge guide.
It provides the reach needed for routing grooves and dadoes farther from the edge, while keeping the router steady and aligned throughout the cut.
How the Extended Router Edge Guide Works
The design is straightforward.
A long plywood arm supports the router, while a sturdy fence registers against the edge of the workpiece.
As you move the router along the board, the fence guides the cut in a straight line.
Unlike a typical router edge guide, the extended arm provides significantly more reach. This makes it possible to rout grooves and dadoes farther from the edge without setting up a separate straightedge.
The arm is adjustable, so you can position the router bit where you need it.
Once the guide is set and locked in place, the fence keeps the router moving parallel to the workpiece edge.
Build the Router Guide from Plywood
You don't need complicated joinery or expensive hardware to make this router accessory.
The main components are a long plywood arm, a sturdy fence, and a few simple alignment parts.
Make the Extended Router Arm
The long arm is made from 3/8" plywood.
Its width matches the router's base, providing a broad, stable mounting surface.
The router attaches to one end of the arm.
To locate the mounting holes, remove the router's factory baseplate and use it as a template.
Transfer the screw locations to the plywood arm, then drill and countersink the holes as needed.
Use the correct mounting screws for your router, making sure they don't extend too far into the base.
You'll also need an opening that provides adequate clearance for the router bit.
Build the Sturdy Guide Fence
The fence is an important part of the jig because it keeps the router traveling in a straight line.
It needs to be rigid enough to resist flexing as you guide the router along the workpiece.
The arm fits between two runners on the fence.
These runners help maintain alignment as you adjust the arm's position.
Because the arm is relatively long, keeping everything square is especially important.
Add an Alignment Block for Accurate Cuts
One challenge with an extended router guide is keeping the long arm square to the fence.
Even a small amount of movement at the fence can cause the router to shift out of alignment at the far end of the arm.
To address this, I added a rectangular guide block that fits into a slot in the arm.
The guide block works with the two fence runners to help keep the arm square as it slides.
A carriage bolt passes through the guide block and arm assembly.
A washer and threaded knob secure the arm to the fence.
Loosening the knob allows you to adjust the distance between the router bit and the fence. Tightening it locks the setting in place.
This arrangement provides the adjustment of a conventional router edge guide, but with much greater reach.
Using the Router Guide to Cut Grooves and Dadoes
Once the jig is assembled, using it is straightforward.
Start by marking the location of the groove or dado on the workpiece.
Position the router and guide so the bit aligns with the layout marks.
Then adjust the arm until the fence registers firmly against the workpiece edge.
Tighten the knob to lock the setting.
With the workpiece securely clamped, guide the router along the board while keeping the fence in contact with the edge.
For deeper grooves or dadoes, make multiple shallow passes rather than trying to remove all the material at once.
A sharp straight or spiral router bit will help produce clean results.
Tips for Accurate Routing
Before making the final cut, it's worth checking a few things.
Check the fence alignment. Make sure the guide is square and the arm is locked securely before routing.
Support the router. Because the arm extends beyond the router base, keep the jig properly supported and avoid applying excessive sideways pressure.
Make a test cut. A test groove in scrap wood lets you confirm the distance from the edge and check the fit of the mating piece.
Use shallow passes. Removing material gradually reduces the load on the router and helps maintain control.
Check the workpiece edge. Since the guide follows the edge of the board, that edge should be straight. Any irregularities can be transferred to the routed cut.
A Simple Upgrade for More Versatile Routing
A standard router edge guide is useful, but its limited reach can be frustrating when you're working on larger panels or cutting joints farther from an edge.
This shop-made version solves that problem with a long plywood arm, a sturdy fence, and a simple alignment system.
It's inexpensive to build, easy to adjust, and provides the control needed for cutting accurate grooves and dadoes.
Best of all, it's the kind of jig that can stay with your router and get used again and again.
Learn More About Cutting Grooves and Dadoes
A reliable router guide is only part of the equation. Knowing how to set up and cut grooves and dadoes makes a big difference in the quality of your joinery.
Explore our guide to Cutting Grooves and Dadoes for practical techniques, tool setups, and tips for making clean, accurate joints with a table saw or router.
LEARN HOW TO CUT GROOVES & DADOES → Get Better Results with Your Table Saw or Router
