How To Get Parallel Lines on Curved Pieces
Learn an easy method for drawing parallel curved lines
Creating a parallel straight line is easy – just move the straight edge over the desired width of the piece. On a curve of uniform radius you just adjust the compass or trammel points and create a perfectly parallel line. Neither method will work on a piece that has a changing radius curves or an S-shaped piece.
Mickey Callahan uses a shop-made tool to create a parallel-sided template for his gooseneck molding template, but you can use the tool and the technique for any kind of shape. He employs a disc, whose radius is the same distance as the desired width of the template or workpiece. A nail in the center of the disc runs along the existing curved edge while a pen on the outside of the disc creates a line exactly parallel to the existing curve. It’s that simple.
Bandsaw your disc. Calculate how wide you want the workpiece to be, set a compass to that distance and draw a circle on some 1/8-in. thick MDF. Bandsaw just outside the line.
Run the brad along the existing finished edge of the template and at the same time hold a pen against the point of the disc furthest from the brad. This will create a perfectly parallel line.
Photos: Mark Schofield