Just had a bad experience-whilst these days one is advised to use multiplat risers and mooring warps the fact that three strand twisted rope can unravel is not greatly emphasised-just that there is a possibility it can.

I set up my new star mooring in the summer and was pleased how the three anchors had bedded in. As reccommended I used a top swivel and a twisted seasteel(polypropelyne) riser-as I had aquired a large quantity of this rope.

Checked it last week after some quite harsh weather and some two feet of the riser has unravelled just below the top splice so be warned!

I assume that the swivel had basically locked under load combined with shifting wind directions-or something like that.

Replacing it with a multiplat riser plus upper and lower swivel next week.

I have noticed, over the years, that several boat-yards on the East Coast, use a bowline and then splice the tail back into the riser, seems to work for them. might be worth a try.

It is noticeable how on different rivers there are completely different methods of laying moorings and different materials used for risers. On some rivers only chain is used wheras on others polypropolene is used. Curiously the rivers with the fastest tidal streams don't seem to use chain.

Polyp. is considerably stronger than chain-for eg. 10mm chain often used as a riser starts to stretch at about 2 tons breaks at about 6 tons.One inch polyp.has a breaking strain of over 10 tons.

According to my cure all book on Anchoring and Mooring a boat such as my 33ft. motor sailor with relatively high windage will pull a snatch load of about two tons in hurricane force winds(plus 100mph) with associated high wave conditions.

Great thing about the plastic is that it doesnt corrode and loose strength so as long as whats on the bottom is sound.

Most oil rigs now use plastic-be it carbon fibre based ropes to moor and all fish farms use either multiplat or twisted polyp.as moorings.