Fiberglass protection against line chafe

[John_Trusty]

What should I use to protect fiberglass against chafe by lines around a sharp corner? This is common on modern catamarans where all lines are lead to a common box near the helm. All used cats I've seen have this serated fiberglass at the top of the line area (see photo of mine where dark areas are completely through the gelcoat). Stainless chafe guards for flat decks are sold, but nothing that bends around a 7mm (5/16 inch) thick structure that is curved.

Best options I considered was a custom thin stainless or starboard strip, through bolted around the leading edge. Better material?

[Bellinghamster]

Yep, stainless. Anything plastic (Starboard, etc.) will likely wear or melt.
If you're capping with thin stainless (thinner than 16 gauge, ~1/16", 0.060") , be sure to fill and fair the existing groves worn in the gelcoat/fiberglass before covering, else the stainless might deform into them. 16, 18 or 20 gauge (0.060" to 0.0375") all feel suitable. 20 gauge can probably be formed by hand, but can be tricky to drill without catching/deforming (hint: use a stepped drill bit). Consider attaching with adhesive (M VHB tape, 3M4200 or 5200 adhesive caulk or similar) rather than screws/bolts. Cleaner look, no screw heads to chafe and no possibility of leaks/wet core.

[wyb2]

Smooth stainless is the best material for a chafe guard/edge protection. It’s easy on the line and will never wear through. Starboard (hdpe) will wear through, probably faster than the original fiberglass edge.

By the way, I don’t see the photo you referenced.