Jacklines are now available from Westpac. ISAF and US Sailing specify webbing that has a 4500 pound breaking strength. We are using webbing with a 9800 pound breaking strength and the complete jackline has a breaking strength in excess of 5000 pounds.
The above image was taken with over 5000 pounds of pull on the test sample and there was no damage to the stitching or webbing. After considerable research and testing we have found that using a bar-tack stitching pattern with a reinforcing piece inside the joint provided the best strength for this application. We did test the “double W” stitching pattern commonly used on slings (and some off the shelf jacklines) and found it failed below 5000 pounds.
All jacklines are made to order. The standard model has a sewn eye in each end, a large one for the forward attachment point and a smaller one on the aft end so that you can have a lashing to adjust the tension of the jackline. If measuring your vessel is not practical we can also provide jacklines with the forward sewn eye and no eye on the aft end. One can use cleats in the stern of the vessel to attach the webbing which will provide an acceptable connection (although not quite as handy).
They are constructed from 1″ polyester webbing treated with NanoSphere® technology which provides for longer life due to its dirt repelling properties. While we sell this webbing by the foot it does require a heavy duty industrial sewing machine to properly stitch.
If you need further information or wish to place an order, call Rollie at (253) 627-6000. There is also more information at http://westpacmarine.com
On Rope by Bruce Smith and Allen Padgett
Load Testing by Evans Starzinger
We tested all of our samples between a large tree and a loaded dump truck (fortunately we have both). In line was a 10,000 pound hydraulic ram and a load cell. The hydraulic ram did not provide enough length of pull to get all of the slack out of the system and then pull for the actual test. Using the dump truck allowed us to pre load the setup and then use the ram to bring it up to our desired tension. The 10,000 pound digital load cell provided us with a quick and accurate way to measure the strain from a safe distance. This is why you see pine needles in the photos.