As a preservation carpenter or cabinet maker a common task that comes up is replicating a molding you find out in the world. Unfortunately most historic sites, museums and stores will not let you pop off a piece of molding to directly trace its profile — no matter how politely you ask. That’s where the molding comb, a.k.a profile gauge, comes in handy. This seemingly simple tool works by pressing it up against the molding you want to capture, and pressing the little feelers against the pieces so they take on the shape of what it’s pressed against. This works much the same way as a common desktop toy from the 1980s with a ton of metal pins held in a grid that can capture whatever you press into it. Once you have the profile you can take the gauge and trace it onto paper thus transferring the profile. This tool also works well for wood turners.
When it came time for me to try and find my own molding combs, I was surprised by how few are even on the market, let alone quality versions. As a kid I remember playing with some versions of this tool made from a series of metal pins, they were often very stiff to use and once a pin got bent, rusty or lost the tool usually became very hard to use. When looking for one of these tools you’ll want to seek out a model that has pins or blades that move smoothly but are kept under sufficient tension to retain the shape you are tracing. You also want to have the finest/thinnest blades you can find as the higher resolution will result in smoother curves. Some of the cheap import models yield results that look like an old 8-bit video game with jagged edges.
The best ones I could find on the market today I bought from GarrettWade.com, and you will pay a premium to get a quality tool you may not use everyday, but I believe the much higher quality results are worth the extra expense in this case. Pictured above are all 3 sizes they offer, and coming from Europe they are in metric sizes roughly on the order of 6″, 12″ and 18″. What I like about them is the fairly fine granularity of the blades, the nice amount of tension on the blades which hold a profile well, and the way one side is triangular and one side is round making it easier to get into odd places. For exterior work the plastic surfaces will not rust which comes in handy when working out in the weather.