New here with rubber gunnel question

[Walaby]

Hi all - I'm new to this site after loitering on the edge for a while. I really enjoy the leaning experience that I find reading everyone's posts! Learning new skills and problem solving is for me (& many of you I'm sure) a big part of why I love boats. I have a steel 10 ton 1980 S&S 34 design with a Volvo MD11C & 110S sail drive on the NSW south coast in Oz and will be slipping her next month. She has been a bit neglected of late and the timber rubbing strip / gunnel has rotted and is literally falling off and as it looks like more work than I'm prepared to do to replace it with timber along with the many other slipping jobs I've bought 4 x 5metre length's of thick black heavy duty extruded "L" shaped rubber with cushioning on the the longer side used mostly for docks / wharfs I suspect. I'm wondering what product would be best to attach it to the pre prepared ie. cleaned & sanded steel gunnel (deck / top sides.) I bought a cartridge of black Sikaflex - 291 and planned on using this but would be interested in hearing others views and opinions?

[barnakiel]

Rubber is difficult to glue. I would not use Sika unless they do make a purpose formulated one.

Rubber is often fixed with fasteners when it forms a rubbing streak / gunwale.

b.

[Walaby]

Thanks for that - this particular Sika product (not sure if Sika Marine 291 is international Sika line?) does not specifically mention rubber but does include wood, metal, GRP, ceramic & painted surfaces. I would like to avoid fasteners if I can as it is just another place where water can intrude with a metal hull.

[Hudson Force]

My large black rubber rub rail was factory affixed with epoxy. I replaced it in 1985 and attached it with 3M5200, but it seem to drift when stressed. I now have returned (since 2012) to securing it with "G-flex" epoxy and I'm very pleased with it.

[Walaby]

Thanks for that Hudson Force your rub rail looks to be a similar thick rubber compound to what I am going to use. G Flex looks to be a west system epoxy glue which also doesn't specifically mention rubber as a recommended use but good to learn that it has worked for you over that length of time. I sent a question to Sika technical advice Australia and they responded with:
"I would not recommend Sikaflex 291 for a rubber application as it will bleed through from the reaction of oil in rubber with the polyurethane.The only thing I could suggest for you to try in this application would be our Sika Contact 4600 which is a contact adhesive used for rubber door trims. I am not sure if it will work on the type of rubber you have I would suggest a prelim test before application." This product is a single pack contact adhesive and I have to see if it's rated for marine external use. I think I like the idea of an epoxy glue better at this stage.

[herculesboat]

Originally Posted by barnakiel

Rubber is difficult to glue. I would not use Sika unless they do make a purpose formulated one.

Rubber is often fixed with fasteners when it forms a rubbing streak / gunwale.

b.

Maybe Mat 450 + Resin + Catalis can Fix it