Grog Sling Details
Purpose: This design was conceived in early April 2014 to create a sling using hollow braided rope without using stitches. A Locked Brummel Splice is used in a non-standard way – tension tends to enlarge the loop.
Technique: For photography, a short sling is shown here. In practice the loop must be much longer: the buried tails must be at least 30 times the rope's diameter. In smaller slings the two ends may overlap as shown in Frame 21. The ends should always be trimmed obliquely to minimize fiber kinking in the outer layer.
Strength: Testing by Evans Starzinger showed that, with long enough buried tails, breakage occurred at the Brummel at over 90% of the rope strength - close to that found when short tapers are employed on buried ends. Used as a sling, a strength over 180% of the rope strength should be expected, close to that expected using stitched ends. However, Starzinger also found that this type of Brummel without the buried ends just pulled apart and that a small sized sling with short buried ends was also very weak.
Advantages: Using Dyneema, this is a quick way to make a very strong Sling. It avoids the need for stitching the buried ends and the sling strength approaches double the line strength. It is readily checked: the Brummel is visible so that it is easy to ascertain that neither of the buried ends has begun to pull out.
Disadvantages: Because the ends are not stitched, repeated use and manipulation is likely to loosen the Brummel splice – which will make the sling weaker. The design also produces a slight bulge at the location of the Brummel Splice.
Long Term Alternative: For a Sling which would be better trusted to remain secure over long periods with repeated use we would recommend either the Brion Toss re-braided Brummel technique or the use of simple long buried ends with stitching.