The Crazy Alberto knot is used for tying a leader to spectra.
Fluro to Spectra, or Mono to Spectra, but not Spectra to Spectra.
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As Jim said you can tie a 4 turn Surgeons Loop in each of the Spectra lines, and make a Cats Paw Connection with the loops.
3 or 4 passes to create the cats paw is very strong.
I know a few commercial guys make the connection that way.
Simple to tie and very strong.
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Lately if I want to make a Spectra to Spectra connection I make a Splice.
I use a 12 ft. piece of 100 lb. Hollowcore Spectra and using a latch needle I pull a doubled section of 65 lb. Spectra up into it.
6 ft. on each side, then tie an over hand knot on the ends to create the finger trap.
-The strongest piece of line on the reel.
