Introduction
The Incra LS17 Super System is the ultimate, top of the range fence system for your router table, drill press or band saw. Incra have a well-deserved reputation for producing versatile and highly accurate tools and the LS17 Super System brings it all together in one package.
Incorporating their patented LS (Lead Screw) technology, this is not just a fence but a complete joinery system that makes complicated joints like through and blind dovetails quick and easy to cut on your router table. It’s been described as “one of the major milestones in modern woodworking accessories”
System Components
When you first look at the Incra LS17 Super System what immediately strikes you is there’s a lot going on. It’s clearly not just another router table fence. To get a better feel for it we need to break it down into the component parts. They are all available individually but in the Super System they’re all packaged together. You get the following components:
- INCRA LS17 Positioner
- Pro-II Joinery Fence
- INCRA Wonder Fence
- INCRA Shop Stop
- Right Angle Fixture
Specification
We’re going to break it down into two main parts – the components that comprise the fence unit and the positioner.
Pro-II Joinery Fence
The Pro-II Joinery Fence is the base fence unit, the basic building block of the system that all the other components are added to. In itself it’s a fairly standard item – a machined 28″ extruded aluminum one-piece fence section with a T-slot and a heavy duty 13″ stop extender bar that telescopes from either end of the fence to stop cuts on longer boards. It attaches to the LS17 positioner via a T-slot on the rear of the fence and could be used on its own, but really its primary role is as the base for mounting the Wonder Fence.
INCRA Wonder Fence
The Incra Wonder Fence is essentially a very sophisticated two-piece split fence which attaches to the front of the Pro II Joinery Fence by means of the T-slot running along the front of the fence. The infeed and outfeed fences are both 14″ long, precision machined from heavy-gauge aluminum. They are machined flat on their faces and the opening is adjustable to handle different sized router bits. With the fence halves slid completely together, there’s a 1″ square opening which accommodates smaller cutters while still giving you a continuous upper surface. The gap adjusts to 4-1/2″ to accommodate large-diameter bits, including the largest raised panel bits available.
One of the advantages of a split fence is the ability to adjust for offset between the infeed and outfeed sides for jointer applications. Traditionally you insert shims behind the outfeed fence, but Incra have come up with a much better method with the Wonder Fence. A pair of opposed, CNC-machined wedges behind each fence half provides a true, continuous micro adjust for the relationship between the fence halves, and laser engraved offset scales are marked every 2/1000″ for an accurate reference. It’s a huge improvement over stacking spacers behind the outfeed fence to achieve an offset.
Dust Extraction & Hi-Rise™ Raised Panel Cap
The first thing that hits you when you look at the LS17 Super System is the unusual location of the dust extraction port and the strange-looking high-rise support that looks like something you rest your coffee on.
The usual set up for dust extraction on a router table fence is to have a dust port on the back of the fence immediately behind the opening. This isn’t possible on the LS17 Super System because that’s where the fence attaches to the LS Positioner. Putting it on the end of the fence is really the only place it can go and in practice it works very well thanks to the enclosed fence body.
The high rise support is what Incra call the Hi-Rise™ Raised Panel Cap. It mounts on the basic fence unit, the Pro-II Joinery Fence via curved risers bolted to a T-slot running along the top edge. It’s removable and most of the time you won’t have it installed (unless you want to rest your coffee on it). A slotted bracket extender plate attaches to the risers and the high level fence bolts to that and can be adjusted backwards and forwards until it’s perfectly aligned to the front faces of the Wonder fence. In use it provides support 8″ above the table and simplifies vertical profiling on tall workpieces.
INCRA Shop Stop and Right Angle Fixture
The final two components of the LS17 Super System are the Incra Shop Stop and the Right Angle Fixture.
The Shop Stop is adjustable up and down, it can be reversed, and it has a screw-based micro adjust. It’s also expandable – the top section can be slid into a second channel on the base section to make the interior wide enough to span an INCRA fence and a wooden sub fence of up to 3/4 inch. INCRA’s patented positioning mechanics make it deadly accurate and completely repeatable.
For a fixture that is the most un-sophisticated looking component in the whole LS17 system, the Right Angle Fixture is what allows you to use this fence system for advanced joinery. Used in conjunction with the Wonder Fence, it keeps boards square to the fence and square to the table when routing box joints or dovetails into a board’s end grain.
It’s got a 10″ wide face plate with a number of T-slots that allows you to mount sacrificial zero-clearance backing boards and other custom fixtures. It sits on top of the front rail of the Wonder Fence and there are two adjustment screws which you adjust until the fixture rides the fence smoothly with no play. There’s a third screw that locks the fixture firmly in place for when you’re fixing the workpiece to it.
The whole fixture is solid enough that you can easily clamp multiple boards to it to cut all your joints in one go. Using the right angle fixture, the LS17 super system is capable of producing a variety of dovetail joints including half-blind dovetails, through dovetails, and box joints. Due to the repeatable precision the jig offers, it also allows variations of these joints such as double dovetails. You won’t get that kind of capability on any dovetail jig short of the Leigh D4R.
