Okay - I've (up to this point) posted that I believe a castwell knot is a good fly line >> leader connection. And for my floating lines, I've had absolutely no problems with it...and I've landed some large fish that ripped out a lot of line.
But - I just tried out this same connection on a sinking tip line, and it slipped with VERY light pressure when I was hung-up on a rock today. There's no way I would have landed even a single fish using it with the sink tip.
So, it appears that the "softer" density of floating lines work okay with it, but not the more "dense" sink tip line. (I don't know if "dense" is the correct way to describe the sink tip, but hopefully you catch my drift.
So, I'm back to.....nail knots. I hate nail knots, but I tie them okay with the quick tie tool. So I've managed to "strip" the fly line coating on one nail knot before, so I just doubled the fly line and nail knotted it that way. More secure..? Who knows. It is still more "streamlined" than the castwell, so no new concerns about hanging up in the guides.
So - I was wrong! It won't be the last time for sure
. I think all fly line >> leader connections are somewhat of a compromise, but I'll give nail knots another go.
Castwell knot? Maybe no so much. I'm not real "high" on a knot that only holds on one type of fly line, so I don't believe I'll use or recommend it any longer.