Canadian Woodworking

Plumb Bob

Author: Paul Ross
Published: June July 2007
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Although there are many different styles of plumb bobs, they all, in essence, do the same thing: they enable you to establish a vertical line. Plumb bobs are one of the earliest tools know to man.

The Egyptians made use of them building the pyramids, and the essential design of the bob has remained unchanged since about 1500 BC.

You can use a solid block of wood from a single species (any hardwood will do nicely) or you can glue up a lamination of several species, as I did. I used a piece of acrylic for the toe. The acrylic is glued on with a tenon for added strength. This way there is more surface being glued than just butt gluing the toe onto the wood body. Most bobs follow basically the same shape, although you can alter that slightly.

Size tenon on acrylic toe

Project parts ready to assemble

Turn bead on toe

Turn tenon on top

Finish toe with skew chisel

Finish top with skew chisel

Drill hole for brass eyelet

Finished product



TIP: Beads can be cut with almost any tool, but the skew is the best at cutting beads cleanly. If you cut the bead properly, no sanding will be required.

  • Size a tenon on the acrylic toe using a skew chisel and a pair of calipers. You also need to turn a tenon on the top knob and then drill holes for the tenons on the body.
  • Glue the three parts of the bob together.
  • Shape the bob. Remember to always turn from large diameter to small – this avoids a nasty catch.
  • You can add different decorative features such as a cove or bead. I chose to turn a small bead on the acrylic
  • Turn a tenon using a 3/8″ parting tool so that the piece can be held with a chuck. Keep the tailstock in place for additional support.
  • To shape the smaller parts I used a 3-3/8″ spindle gouge, which can also be used to roll a bead.
  • Remove the tailstock to finish the toe end of the bob with the toe of the skew. This cut requires absolutely no finishing.
  • Flip the bob in the chuck and finish the top end of the bob with the skew.
  • Drill the hole for the brass eyelet.

Besides making a functional measuring instrument, this project is a great practice exercise in tool work.


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