DIY Network

A second method of dealing with a knot is to fill the area with a patch. This is an effective method for repairing a large knot-hole. For this demonstration, we patch an unsightly knot-hole (figure H) with a more presentable knot using the inlay process.

• First, locate piece of stock similar in grain and color that has a knot about the same size as the hole you'll be fixing.

• At the band-saw, cut a slice from the stock 1/8-inch thick (figure I).

• Use a sheet of paper to outline the shape of the knot-hole (figure J).

• Slip a piece of carbon paper underneath the knot-hole and draw the boundaries of the knot-hole on the inlay stock.

• Using a ruler, expand the layout marks around the shape and join the points (figure K).

• Use a scroll-saw to carefully cut out the shape.

• Double-stick-tape the knot inlay onto the knot-hole, and scribe around the edges to define the boundaries using a scoring knife (figure L). Score the lines several times to gently sever the fibers around the knot-hole.

• Using a plunge-router, cut a recess just shy of 1/8-inch in the area defined by the scribed boundaries.

• Apply yellow glue to the recess (figure M) and inlay.

• Once the inlay is in position (figure N), set it with a few gentle taps of a hammer.

• Use wax paper, a caul and clamps to clamp the inlay securely as the glue dries.

• After the glue has hardened, use a hand-scraper to flush up the inlay with the surrounding surface of the wood.

• As above, use naphtha to reveal how well the inlay blends with the surrounding wood (figure O).

• Flip the board over, and fill the back side of the hole with epoxy (figure P) to add strength.

Rather than using a knot, you could also opt to add a decorative touch by patching the area of a knot-hole using custom inlay -- a contrasting wood, a pattern or a geometric shape.
Simple Crack Repair

Here are tips and techniques for using a piece of stock that is cracked or split at the ends. If you can preserve the natural edge of the stock, you may want to incorporate the cracked surface into a piece for visual interest. Splits and cracks can often be repaired simply using yellow glue.

• Place blue tape on the bottom of the crack to act as a dam to hold the glue.

• Use a narrow-tipped syringe to apply the glue and get it into the fibers of the crack (figure Q).

• Use pipe-clamps to pull the split together (figure R) and allow it to cure.

Another creative way to deal with cracks is a butterfly repair. This method is similar to the decorative inlay technique that was used on the knots. A butterfly inlay looks like two dovetails laid back-to-back (figure S). We cut ours from a piece of rosewood to offer a visual contrast against the wood being repaired. The butterfly does not close the gap, but will prevent one from getting larger.

• Use double-stick tape to adhere the butterfly to the stock so that it bridges the gap.

• Scribe around the edges of the shape using a sharp blade, then outline the scribe marks with a pencil.

• Use a plunge router to cut a recess inside the scribe marks (figure T).

• Use a dovetail chisel with beveled sides to make the corners of the recess square.

• Apply yellow glue to the dovetail and set it in position in the mortise. Tap it down secure with a few gentle taps of a hammer.

• Once the glue is dry, flush the butterfly with the surface of the wood using a block plane followed by a hand-scraper (figure U).

What was once an undesirable crack is now a part of the contemporary design.

	Figure V
	Figure W
	Figure X

Decay, Fungus and Insect Damage

Damage from decay and fungus leaves behind interesting patterns and discolorations. When the pattern is edged with black lines that look like ink-lines (figure V), it's known a spalting. This natural imperfection can benefit the look of some pieces, but decay and fungus can leave areas of the wood soft and punky. To save the patterned wood, soak the area using cyanoacrylate glue in the thinnest viscosity available. Flood the areas of the wood with the CA glue. The glue will stiffen the wood fibers and, after a few hours, the treated areas will harden like a rock.

Insect pests cause damage to wood, but don't be too hasty to discard wood that's been infested. Sometimes the effect may be to texture or "carve" the wood in a manner that may be desirable for some pieces.

• If you work with kiln-dried wood, insect pests shouldn't be a problem. The kiln-drying process heats the wood sufficiently to kill pests.

• Air-dried lumber is susceptible to infestation. Ridding lumber of insects may require professional fumigation. If you have a piece of wood with just a few worm-holes (figure W), a repair is simple.

• Select a piece of wood that matches the wood you're repairing. Cut a small dowels from the stock and use a pencil-sharpener to sharpen the tips of the dowels.

• Use yellow glue to seal the holes with the pointed wooden plugs (figure X). Glue the plug tip into the hole, and remove the excess wood using a flush-trim saw. Smooth the surface with sandpaper. With a close match in wood color, the holes practically disappear.