The rule of thumb is to use the largest diameter line you can when hanging a boat fender. Too small a line can cut through a vinyl fender eye like a knife, and larger diameter lines create a stronger connection. Having a better connection between the line and the fender will help keep your fenders working when you need them, in challenging docking situations, and using too small a line diameter voids Polyform's warranty.
Our preference is to use a looped connection with eyed fenders, keeping in mind hole through middle fenders like the HTM will work differently, (HTM Section). A looped connection with a fender eye allows a boater to use a lighter line, which most find easier to handle, while also making a stronger thicker connection to the fender eye. We recommend a splice, like our spliced lines here, or a bowline to make the loop in the fender line. When tying a fender to the boat or dock there are many methods and most work well, but it is common to use two half hitches or a clove hitch. If tying to a cleat a belay looped connection through the cleat or a cleat hitch are common.
Doubled or Looped Fender Connection
Line Recommendation Chart
| POLYFORM MODEL | EYE DIAMETER | RECOMMENDED LINE DIAMETER (Doubled Line/Looped Connection) |
|---|---|---|
| A-0 | 0.6 " | 1/4 " |
| A-1 | 1" | 1/2" |
| A-2, A-3, A-4 | 1.125" | 1/2" |
| A-5 | 1.25" | 5/8" |
| A-6 | 1.5" | 5/8" |
| A-7 | 2" | 5/8" |
| F-1, F-02 | 0.7" | 3/8" |
| F-2, F-3, F-4, F-5 | 0.9" | 3/8" |
| F-6, F-7, F-8, F-10 | 1" | 1/2" |
| F-11 | 1.1" | 1/2" |
| F-13 | 1.2" | 1/2" |
| G-1 | 0.375" | 1/4" |
| G-2 | 0.5" | 1/4" |
| G-3 | 0.625" | 3/8" |
| G-4, G-5 | 0.75" | 3/8" |
| G-6 | 0.875" | 3/8" |
| HTM-1, HTM-2, HTM-3, HTM-4 | 0.625" | 1/2" (Straight Piece of Line) |
| LD-1, LD-2, LD-3, LD-4 | 1" | 1/2" |
| NF-3 | 0.625" | 3/8" |
| NF-4, NF-5 | 0.75" | 3/8" |
| S-1 | 0.5" | 1/4" |
Fender Lines on Hole Through Middle (HTM) Boat Fenders
Our HTM fenders work best with a 1/2 in. diameter line. You'll need a little more line than an eyed fender because you'll pass the line through the entire fender and you'll need a stopper knot on the end. In general we find the following line lengths work for most boats, but keep in mind your needs may be different.
| Model Number | HTM-1 | HTM-2 | HTM-3 | HTM-4 |
|---|---|---|---|---|
| Approximate Line Length | 8' | 9' | 11' | 13' |