I'm about to build a 13'6 skagit.
The guide chart from the producer is listed with snakes. I plan to use the new Fuji torzite instead. Allthough the torzite guides have a minimal ring size, it will still be a bit more narrow than snake guides..
Should I consider increase the ring size slightly, compared with the default setup?
When casting a skagit rod, only running line should run through rings when casting. This shoud probably work well despite a slightly narrower inner diameter of the rings?

- Occasional amateur rod wrapper -

Size will be fine - except your choice of ceramics over wire guides is ill conceived.
Skagit as well as Spey rods are soft enough without creating more "softness". The rod's performance will be severely limited. i.e. recovery rate.
Herb

You should be fine.

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I build many spey rods and never use snake guides.

I'm aware of the discussion on snakes versus ceramics. This is taken into account, and I have settled for a solution. We'll leave it there.

My concern is; should I upscale the ring size (by OD) to get te same ID, or is this not important taken into consideration that running line has smaller dia than ordinary line.
Thoughts about this would be appreciated.

- Occasional amateur rod wrapper -

The only way to know for sure would be to tape up a set and try it both ways. But I suspect you'll be okay with the same sizes you listed.

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