Get More Bang From Your Biscuit Joiner
Improve joints and find new uses
1. Use a biscuit joiner to cut slots for Z-shape tabletop fasteners. You can do this before or after assembly in most cases. Limit the cutting depth to no more than two-thirds of the apron’s thickness.
2. Biscuiting joints in narrow stock risks blowing the blade out the stock’s edges, exposing the slot and biscuit. To avoid this, choose one of these methods of using half-biscuits where they won’t be seen or can be covered with trim.
Reinforce miter [Photo A] and butt [Photo B] joints across the back with half-width biscuits (trimmed flush after the glue dries). You’ll need to cut a slot narrow enough (most likely the 0 or 10 setting) to span across the joint without reaching the edges.
Or, create a joint with a half-length biscuit reinforcement. To do this on a frame, clamp opposing sides to the bench end to end, and cut a slot centered on the seam [Photo C]. Rotate the pieces and repeat for the other ends. Next, clamp the top and bottom rails side by side, and cut slots in the ends across the seam [Photo D]. Repeat for the other ends. Then, glue the frame together with a biscuit in each slot [Photo E]. Trim flush when dry.
3. When planing panels glued up with biscuits, cut a reference slot on an end or edge that will be cut away later, at the same depth as the joinery slots [Photo F]. This shows the biscuits’ location in the board’s thickness, keeping the biscuits centered as you avoid planing too deep on one face. Or if you used two rows of biscuits, it prevents exposing them.
4. Create finger holds on cutting boards [Photo G], or finger pulls on the bottom edges of drawers and doors, by making stacked cuts of equal depth. Sand inside the cutout to remove blade marks.
5. When joining MDF or particleboard—products notorious for not joining well with screws—use biscuits for stronger glue joints.
Help the tool perform better
6. Attach a shop vacuum to your tool’s dust port [Photo H] for better dust collection than possible with just the included bag. Many biscuit joiner dust ports plug easily when using the dust bag.
7. Highlight broad alignment marks with a high-visibility marker. Or, add a fine black line to existing wide lines or notches that might not be easy to align in use [Photo I].
8. Sharpen the blade in your joiner, or upgrade to a new blade when plunging becomes difficult. Keep in mind that sharpening can potentially narrow the slot, making for a tighter fit. So don’t count on more than a couple of sharpenings per blade.
9. With many biscuit joiners, the narrow fence will not effectively support the tool, particularly when cutting angled slots. For more stability, attach a piece of thin plywood, MDF, or hardboard to the fence with double-faced tape [Photo J].
Think outside the (biscuit) box
In addition to standard wood biscuits, Lamello offers plastic and metal versions (above) for special purposes that work with slots cut by any biscuit joiner. We think these have a place in a home workshop.
10. For hard-to-clamp assemblies, K20 plastic biscuits have barbed faces that lock the biscuit into a joint. Used in conjunction with glued wood biscuits, unglued K20 biscuits “clamp” two workpieces together while the glue on the wood biscuits dries.
11. Plastic E20 half-biscuits work as self-clamping fasteners in slots cut across a joint, such as those shown in Tip 2. The splayed pattern of barbs draw components together without glue as they are tapped into place.
12. Simplex metal knockdown connectors work well in applications that require quick or frequent disassembly, such as adjustable shelves or access covers. Adhere one in each slot with polyurethane glue or two-part epoxy, making sure the opposing fastener is reversed. When you assemble the project, the fasteners hook together for a strong joint that’s easily taken apart.
13. For knockdown joinery in more semi-permanent installations, use Clamex S cam-lock half-biscuits [Photo K]. These require a bit more setup than Simplex fasteners, and fit in double-thick slots that house mating fasteners [Photos M–O]. Create the slots by making two cuts with a standard blade, or buy an optional blade that cuts a 1⁄4 " slot [Photo L].
Clamex S carbide reversing blades cutter, no. 132108; 18 pairs Clamex S connectors with screws, no. 145231; 781-585-4364, csaw.com.