Duplicate Moldings - DIY

Jim Lewis

Molding Pattern made out of steel

I sometimes have to duplicate moldings. If I have the right router bit, it’s a snap, but often I don’t. So, I start out with the best that I have and sometimes saw some bevels to further rough out the shape.

Next, grind a scraper cutter to match. This is easier than it sounds. I use a piece of steel strapping, the kind that lumber used to be bundled with all the time. A lot of people have switched to plastic, but if you can find some of the old steel strapping somewhere grab it. The wider and thicker the better!

I clamp an angle grinder in a vise and put on safety goggles and earphones. Sparks fly and the sound is horrible, but better with earphones.

Draw the shape of the molding as best you can and cut it out of paper or thin card stock. Use a sharpie to transfer it to the strapping. Use a steel wheel in the angle grinder to cut out the shape. Keep your cut as perpendicular to the surface of the strap as possible.

You can use this as is or put it in a simple wooden holder to make grabbing it easier. Hold it slightly off perpendicular and scrape, scrape, scrape the wood until it matches the profile. This is a good way to do a short run of molding, Say 20 feet or less.

This sort of spring steel can also be used as a plain old scraper for flattening wood. Grind the edge perpendicular, as flat as possible, and hold it as you would hold a regular scraper.

If you can’t find strapping, and I know it is getting harder and harder to find, try an old bandsaw blade. Grind the teeth off first, and if you can grind the profile on that side, it is likely to have a better temper. If you can find a machine shop or ironworker, ask them for some of their used bandsaw blades. These are often thicker, harder, and wider than what you would find elsewhere. They make excellent scrapers.

To refresh the edge, trace it lightly over the cut off wheel and re-sharpen it. No need to burnish or file, quick and dirty works just fine.

If you have any questions or want to chat about this, find me on Facebook in The Woodworking Group!