Fids

What Are Fids and Why Every Boater Needs One

A fid is a pointed, tapered tool used to open the strands or braids of a rope so that another line can be threaded through — the essential first step in creating a proper rope splice. Whether you're attaching an anchor rode to a shackle, building a soft shackle, or terminating a dock line with a clean eye splice, a fid makes the job possible and precise. Without the right fid, working with today's high-performance braided and double-braid ropes would be frustrating at best and damaging to the line at worst.

The Role of Fids in Anchoring and Docking

In the context of anchoring and docking, spliced connections are far superior to knots in many situations. A well-executed splice retains nearly 100% of a line's rated breaking strength, whereas even the best knots can reduce strength by 30–50%. Fids give boaters and riggers the control needed to work fibers apart cleanly without cutting or fraying, ensuring a professional-grade splice every time. From lightweight hollow fids for small-diameter lines to heavy Swedish fids designed for thick anchor rodes, having the right size and style of fid for your line type is critical.

Types of Fids

• Hollow Tubular Fids: Used with a specific wire or core, these allow you to grip and pull the inner strand of a rope through the outer braid — ideal for double-braid splicing techniques.
• Swedish Fids: Solid, tapered tools perfect for opening up three-strand or single-braid ropes to work in the tuck of an eye splice.
• Marlinspike Fids: Traditional tapered metal or wood tools for heavy-duty work on large-diameter lines and anchor rodes.
• Pusher/Puller Sets: Multi-piece kits that include both a hollow fid and a pusher wire, commonly used for braided rope splicing.

Choosing the Right Fid

The most important factor when selecting a fid is matching its size to the diameter of your rope. Most manufacturers publish fid-length-to-rope-diameter charts — using a fid that's too small can damage fibers, while one that's too large can over-open the braid and weaken the finished splice. Consider the type of rope as well: three-strand twisted nylons require a different approach than modern hollow-braid or double-braid UHMWPE lines used in high-load anchoring applications.

Top Brands in Fids

Samson is one of the most respected names in rope and rigging, and their fid offerings reflect decades of expertise in line construction. Because Samson manufactures a wide range of high-performance ropes, their fids are engineered to work seamlessly with specific Samson line diameters and constructions — making them a natural choice for anyone already running Samson anchor lines or dock lines.

Ronstan brings its hallmark marine-hardware precision to the fid category, offering tools built for sailors and riggers who demand reliability. Ronstan fids are a trusted choice for performance sailors who need clean, repeatable splices on running rigging and anchoring systems alike.