This isn’t your art class compass

At my house, your house, most houses—the walls, floors, corners are never really true. To fit door trim tightly to a wall I had to scribe against wavy, bumpy, curved plaster walls.

Scribing is a skill worth mastering if you want tight fitting molding and trim. Most carpenter use a compass to scribe, and not having once since grade school I visited my local home center. Both stores offered the General compass for about $7. Figuring this would be the right tool to transfer the bumps of my wall to a piece of stock held 90 degrees from it, I bought it. This compass didn’t work well because the leg that held the pin also held the adjustment screw that determines the distance between the pin and the pencil. For my situation, I had to drag the pin along the wall, and it was nearly impossible foe me to do what with the screw sitting about an inch proud of the leg. I also found that it’s possible to inadvertently squeeze the pencil and pin together while you’re dragging it, which compromising accuracy.

So I needed a new compass, but neither the arts and crafts store nor the big box retailers had promising ones. But Lee Valley has several, depending on what you want to spend. I like the $35, 6-inch compass made from solid stainless steel (far right in photo). The design is simple, but works really well. The pin side sits flat against the wall because the all the adjustments happen on the leg holding the pencil. There is no chance of the legs moving closer together because a thumbscrew locks them into place at the distance you set.  The pencil is also held at an angle so the pence and the pin can just about touch, delivering a tight fit.

Please post your scribing tips.