Filling Holes: Wood, Dough, Putty or Plugs?

It’s a common sight, but not a pretty one.

Regardless of the age of your house, it is punctured with holes: nail holes in the woodwork, holes for non-existent cords in your hardwood floors, old screw holes around your door hardware.

And there is no shortage of materials available to us to fill these unsightly holes: wood putty, wood dough, wood filler and, of course, real wood.

But how do we know which to use?

Wood Putty – This is a pre-tinted, non-hardening product intended to be used on holes less than 1/8” in diameter in surfaces which are finished, such as the top of a table or the varnished baseboard around your dining room. Since it is non-hardening, it does not have to be sanded – which would damage the surrounding finish. But since it does not harden, it is not suited for holes larger than 1/8”.

Wood Filler and Wood Dough – Two names for the same type of product: a non-tinted, pliable, synthetic material that hardens in the wood. Appropriate for holes less than 3/8” diameter in bare wood. Typically this product is packed into the hole using the blade of a screwdriver, mounded slightly to allow for shrinkage, then sanded smooth, stained and finished. Warning: not all of these products accept stain equally. Test on scrap material first.

Wood Dowels – Typically made from oak or maple in three-foot lengths in diameters from 1/8” to 2” or more, wood dowels would seem to be the perfect material for patching larger holes – BUT they pose a problem. Wood dowels are like a bunch of soda straws: open at either end. As a result, they absorb twice as much stain and finish as the side grain surface around them, which means they will be much darker than the surrounding wood. If that is what you want, fine. But if you want your repair to blend in, not stand out, read on.

Wood Plugs – Cut from the side grain of a board, wood plugs have a visible wood grain rather than end pores like a dowel. You can buy them on-line or from well-stocked hardware stores, but I prefer to make my own. You can purchase a set of three plug cutting bits (1/4”, 3/8”, ½”) for around twenty dollars. Mount them in your drill press and you can then select a donor board with the grain that matches the grain around your hole and cut a plug that will literally make the hole disappear. And unlike a dowel, it will absorb the same amount of stain or finish as the wood around it.

Tip of the Week: Before inserting a dowel or plug, use a cotton swab to coat the inside of the hole with glue. By putting the glue inside the hole rather than on the outside of the plug, you avoid ending up with a smear of glue on top of your wood.