Joinery Class Tongue-and-Groove Making Perfect Tongue-and-Groove Joinery on the Router Table

By Andy Rae

Edge-to-Edge End-to-Edge Solid wood paneling, Groove Web frames, cabinet backs, frame-and-panel fl ooring assemblies

S ti l e

Rail

Plywood Tongue

Wood edging Edging Common applicati ons: Shelving, cabinet sides • Edging • Web frames • Cabinet backs • Wall paneling • Flooring

With its relatively short groove, the tongue-and-groove When it comes to cutting the bits that allow spacing the tongue that �its into a shallow joint, the router table makes cutters to suit your stock’s quick and precise work of the thickness. All these bits cut the joint is woodworking’s diminutive job, thanks to router bits that usingpro�ile a instraight a single bit, pass—a rabbeting much cousin to the mortise-and-tenon. cut complementary tongues more desirable approach than Thankfully, it’s much easier to and grooves. Think of it as make, in large part due to modern cut ’n go: Rout each edge, and bit, or slot cutter to shape the routers and router bits. The you’ve made a perfect joint. Withjoint, awhere tongue-and-groove inconsistent stock bit shorter tongue is a good choice for There’s a range of bit designs orthickness bits in your can screwrouter you table, up. registering parts, such as when on the market, from single, �itting wood panels or boards for recon�igurable bits that you cabinet backs and �looring (in take apart and rearrange to cut a few accessories, and some which case the joint is typically both sides of the joint, to 2-bit, simple techniques, you’ll get assembled60 woodcraftmagazine.com without glue.) Oct/Nov 2016matched sets and “convertible” reliable cuts every time. Mill stock with straight Basic T&G Design and parallel edges.

For strength and aesthetics, the Groove dimensions: 1 3 1 1 ⁄4- ⁄8" wide × ⁄4- ⁄2" deep Tongue dimensions: 1 3 1 1 tongue should slip snugly into ⁄4- ⁄8" thick × ⁄4- ⁄2" wide Fitti ng the Joint Shoulders meet theits groove tongue (whether about one-third the joint at joint line. is to be glued or not). Making Make tongue at least one-third the thickness of stock for strength. the thickness of the stock Leave small gap between tongue and ensures that all parts of the groove for a ti ght fi t at shoulders. pro�ile are as stout as possible.

Router Table Speed A Dressy Opti on control dial Some router bit Setup manufacturers off er matching bit sets that incorporate When routing tongue-and-groove a bevel in the profi le. The resulti ng V-grooves in the assembled panel joints, consistency is key for add an aestheti c element thea good right �it tools, and part accessories, alignment. Dial it down. Use a variable-speed while hiding any slight For predictable results, use router, and keep your speed around misalignment of the parts. 15,000 RPM to lower vibrati on and and setup. First, it’s important reduce stress on the router and bit. to use a powerful router with variable-speed control to ensure V-groove paneling smooth, safe cuts when using these big, heavy bits. Make sure your router table is equipped with a straight, �lat, split-fence with an adjustable center opening. Alternatively, you can saw out an opening for the bit in a thick auxiliary fence, and clamp that to your existing fence. A featherboard clamped to the fence ensures consistent grooves and tongues, and pushsticks and pushblocks keep your hands safe. Tongue-and- groove bits create a lot of chips, so dust collection is crucial.

Decorati ve V

1 The right stuff . For ti ght, crisp joints, equip your table with a 1 ⁄2 hp (or more) variable-speed router, a split fence, a featherboard, a heft y pushblock, a plywood pushsti ck, and through-the-fence dust collecti on.

Photos: Andy Rae; Illustrati ons: Christopher Mills Oct/Nov 2016 woodcraftmagazine.com 61 Joinery Class

Making the joint with a 2-bit set

Rout the groove fi rst...

Using a mating 2-piece set of router bits is one of the most accurate and ef�icient ways to make the joint. Mill the groove �irst. Start by aligning the groove bit’s ball bearing tangent to the front face of the fences, and then center the cutter across the thickness of test stock milled to the desired dimensions. Use a featherboard and a pushstick to make the cut, routing the groove in a single pass. Rout the tongue next, using the routed groove to help set the tongue to the correct height and again aligning the bit’s bearing tangent to the fence. Make a test cut to check that the joint �its and the board surfaces align, and then rout as before, feeding smoothly with consistent pressure.

Tongue 2-cutt er cutti ng bit grooving bit

Nut Bearings

Keep the groove smooth. A fence-mounted Spacers featherboard ensures Washer a groove that’s parallel to the board faces. Mati ng bits for effi ciency and accuracy. This 2-piece set from Using a pushsti ck keeps hands clear of the 1 1 Freud accommodates stock thicknesses from ⁄2" to 1 ⁄4". One cutt ers while off ering more control for a of the bits cuts the tongue, and the other the groove. You can smoother cut. For consistency, make all cuts fi ne-tune the cut on both bits by adding or subtracti ng spacers. with the “show” face against the table.

Routi ng Ends Cutting tongues on the ends

of work is handy for rail connections, such as when making web frames for drawers and other case components. Narrow rails can be tippy against the fence, so you’ll want to back up the cut with a pushblock for safe, square cuts. Bonus: The block prevents Back it with a block. Use a squared pushblock to keep the workpiece steady against tearout at the same time. the bit’s bearing and the fences while you rout, and to prevent tearout at the back.

62 woodcraftmagazine.com Oct/Nov 2016 ...then tackle the tongue

Plywood spacer

Eyeball the height. Set the tongue bit’s Rout the tongue in one pass. Keep the pressure steady by height by lining up its cutting edges bumping out the featherboard with screws and plywood with the groove, and then make a test spacers to clear the taller cutter. Use a pushstick as before cut in scrap to verify your setting. for a smooth tongue with a consistent thickness and width.

T&G for Less A Good Lookin’ Fit For around $50, you can buy A well-made tongue-and-groove joint presents a gapless seam a single WoodRiver bit that along the shoulders, or face, with a tongue that fits snugly will cut tongues and grooves into the groove. To ensure tight shoulders, look for a hairline 3 in ⁄4"-thick material. Use both gap between the end of the tongue and the bottom of the cutters to make the tongue; groove. Some manufacturers build this into their bit design. If then use a single cutter for the your tongue bottoms out, make a pass with the tongue’s edge groove. See Buyer’s Guide, on the jointer or with a couple swipes from a hand plane. p. 64 for ordering information. Groovy joint. You can make wide panels, such as for cabinet backs, by joining a series of tongue-and- groove boards together. A good joint shows tight shoulders with a small gap visible inside the joint.

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