Hermitt Let me get this straight
Are iyou saying your problem is how to connect a double braid rode to a triple strand nylon rode?
You can't do a short splice in this case. Look at the picture of an eye splice. If you want to connect two straight lengths of triple strand you can basically splice them together just like an eye splice but without the loop. First splice one into the other starting some length away from the end, then unlay the strands of the second line and splice those into the first. You end up with a straight, very strong line but with a big bulge in the middle where the line is about twice as fat as the rest. After each splice put the splice on the ground and roll it with your foot to smooth it out and make it round.
So getting back to triple strand to braided. I say go with an eye splice on each, then pass the straight end of the braided through the eye of the triple strand, pass the straight braided end through the eye in the braided rode and pull it all the way through to cinch it up on the braided line. No shackles, no chain, just rope and pretty strong. It will come apart fairly easily but you might need your rigging knife to pry it apart. When I made my Jordan Series Drogue I bought lengths of 5/8 braided line I got as remnants at Defender and I connected them this way. Since there was already one joint in the design like this the extra joints don't weaken the rode any more than the first one. Each joint further away from the boat has less stress on it. I made a bunch of eye splices in braided line with my magic splicing tool so I got a lot of practice. The magic splicing tool was invented when I paid 11.95 for the best tool ever, but it was a brazed assembly and broke after a couple uses. The coat hangar has no joint to break and is good ductile strong material. The little hooks on the end are to hook into the sheeth to pass it through the core. You hook it in place then use whipping twine to hold it or just some painters tape will work with care. Learn how to make braided eye splices it is a great thing to learn for your boating toolkit. Paying someone to do this for you is a waste of money, just follow the directions step by step and you will have a eye splice as good as any.