Amsteel/Dynex to double braid splice?
 

As Amsteel and Dynex are so strong maybe it makes some sense to treat it like wire in the way we used to do wire/rope halyards?

Anyone have an Amsteel to double braid splice?

There is an older post in spar talk http://briontoss.com/spartalk/showthread.php?t=1936 that discusses this question although I find it hard lacking pictures to follow what is being said.

I also found this set of pictures that shows the splice you want. I have no idea how strong it is and I have not tried it or tested it.
http://community.webshots.com/album/576708986RjiYIB

Personally, I just faced this question and what I just bought is 90 feet of 3/16 Amsteel and 50 feet of 3/8 Tenex. My plan is to have the Amsteel run the entire length of my halyard and have the Tenex be the cover for the lower section. Tenex is a 12 strand single braid polyester with a coating to make it snag resistant. I intend to bury 6 of the 12 Tenex strands (tapered) at the joint and just whip the joint enough to keep the other 6 strands that are not buried from unraveling. I have tried this and it makes a smooth transition. I did not want any question as to the strength, which is why I am using a full length of Amsteel. The total cost is about the same as using 40 feet of Amsteel and 50 feet of 7/16 XLS and that probably cannot be spliced anyway. I wanted a lower section with a 7/16 diameter so it is easy on the hands and that is about what you get with the Amsteel inside the Tenex.

Allen

Taper
 

Hello,
The Amsteel/Tenex splice is a nice one; it would be good to be able to have an all-Dacron tail, just to make things cheaper, but this can be difficult. The splice at the link is clever, but I'd be amazed if it generates acceptable strength; too much load on too small a portion of the core, and too little friction on too-small a section of the cover. Posting a splice like this, without conducting a destruction test, is like coming up with a clever new recipe for brake pads, but not actually trying it out before recommending it.
Fair leads,
Brion Toss

I was told by Samson that you cannot splice 12 strand Amsteel to a poly core because the stretch is different between the two materials. I didn't really believe that but I didn't want to take a chance so went with the full length Amsteel core for this and some other reasons. I made the halyard up today but replacing the wire winch with a standard winch will take a few more days (wood plugs, primer, paint, paint...). I will test it after that. The Tenex is a bit stiff and slick but I assume it will soften with usage. The only hard part was threading the Amsteel through the Tenex and it was only hard because there was so much of it. I wrote up what I did here: http://l-36.com/halyard.php. I will add more detail and pictures to the page next week. If you have any suggestions as to improvements, I am all ears.

By the way, the tail with the Amsteel core plus the Tenex cover (finished diameter of 7/16) cost about the same as 7/16 XLS double braid. I don't think you can save much by using an all poly tail unless you go with a smaller diameter.

Allen