Here are general recommendations for single braid UHMWPE line such as the Amsteel we are using, by McCarthy and Starzinger from US Sailing.
The source is a pdf [/URL]from January 2010. They present it to reflect collective wisdom and experience from multiple communities of users over a number of years.
I've hi-lited a few points that were new to me, if not to you.
As in all line, splices are preferred to knots where possible. As with all line, a splice in Spectra® will be stronger than a knot. Generally a splice will be 90-100% of the line strength while a knot will be only 55-60% of the line
strength (excluding the slippage issue discussed below).
There are two splices in common usage with single braid Spectra®: the locked Brummel
(
http://www.neropes.com/SPL_12Strand_...ceBrummel.aspx) and the Bury
(
http://www.samsonrope.com/site_files/12S_C2_EyeSpl.pdf ) . The Bury is perhaps the simplest of all slices in all types of line. After making it once with instructions, most people can make it again without instructions. This splice
must absolutely be lock stitched or it may slip under low load. With lock stitching it is absolutely secure. The locked Brummel is more complex and many people will require instructions each time they make it. In return for this complexity, the locked Brummel is more secure (without lock stitching) against low load slipping.
However, if the buried tail is too short on a locked Brummel, the whole load can come off the ‘knot like’ locking portion and it will break at much lower than expected load. Recent testing indicates the buried tail must be 72 times the diameter of the line, which is longer than previously recommended and typically used in practice. Both splices are acceptable, but the Bury splice is simpler and more resistant to improper construction, so is generally used.
One key to proper construction for both splices is a long smooth taper on the buried tail. If the tail is not tapered it will create a stress riser at its end and the splice will fail at that point. A second key to proper construction is that
Spectra® is more slippery that almost any other fiber and splices can slip at quite low loads if there is an oscillating or jerky loading. To prevent this all splices should be lock stitched and the throat whipped.
The document goes on to describe (even untreated) dyneema as among the most abrasion-resistant fibers -- that's to you, Grizz --saying that the best protection, if needed is more dyneema, and that signs of abrasive wear are obvious: fuzziness.
There is also this suggestion I think we have not seen before here:
Knots should have the tail lock stitched to the standing part as this will eliminate the risk of slippage. To untie these knots you can pull the tip of the tail away from the standing part and slice the lock stitches with a razor blade.
Dunno that many campers will whip out a needle in a pinch to inject a few threads, but there it is.
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