How to Use a Rope Thimble Clamp Set

by Will Charpentier

When you need to put a temporary loop in the end of a length of wire rope, in order to attach a hook or shackle, then install a thimble using a thimble and clamp kit. The thimble is a strip of metal bent so that it resembles a pear in profile. The thimble protects the wire rope from chafing against the hook or the shackle. The clamps secure the end of the wire rope to the rope's main body, holding the thimble in place.

1. Remove the loosely-attached nuts by hand from the U-bolt of one of the clamps. Slide the roddle -- the saddle-like attachments to the U-bolt that makes up the rest of the clamp -- off the U-bolt, to have it ready to install quickly.

2. Wrap the end of the wire rope around the thimble. Make sure that the the end of the wire rope extends far enough past the end of the thimble to install two clamps.

3. Pick up one of the clamp U-bolts and slip it down over the end of the wire rope you just wrapped over the thimble. Make sure the clamp is as close to the tip of the thimble as possible.

4. Slide one of the roddles onto the U-bolt. Thread the nuts onto the ends of the U-bolt. Tighten them securely with an adjustable wrench. Attach additional clamps as necessary -- one for every 1/4 inch of the rope's diameter.

Items you will need

  • Adjustable wrench
  • Leather gloves
  • Long sleeves
  • Long pants
  • Safety glasses


  • Always install at least two clamps.
  • Apply one clamp per 1/4 inch of diameter, with a minimum of two clamps, on wire rope. For example, (1/2) / 1/4 = 2 clamps; (1) / 1/4 = 4 clamps.
  • The correct spacing for clamps is calculated by multiplying the diameter of the rope by 6; the result is the number of inches between clamps. For example, 1/2 x 6 = 3, or 3 inches between clamps.
  • The number stamped on the roddle is the size of rope the clamp is intended for.


  • Wear leather gloves, long sleeves and pants, and safety glasses when working with wire rope.

About the Author

Will Charpentier is a writer who specializes in boating and maritime subjects. A retired ship captain, Charpentier holds a doctorate in applied ocean science and engineering. He is also a certified marine technician and the author of a popular text on writing local history.