On warnings about silicone and later

problems glueing, epoxying, to repair, somehow I haven’t stumbled into this problem. It would be easy for me to conduct one or more experiments for my own education. Can others give me a short list of silicone-containing products? I would probably test both a fabric repair, using a urethane as the repair glue, and a hull surface repair on a composite hull, using West G-flex as the repair resin.

Don’t use silicon based products for
your implants.

Which implants?

Bad String!
Bad, bad String!

But seriously, it is my understanding that if silicone caulk is used for sealing or bonding purposes that even if the surface is well scraped and sanded that nothing except more silicone caulk will stick.

Mind you, I have not run any tests - this may be an old wifes tale.


More like a suburban legend. But it
might be true.

Madonna wasn’t afraid of silly cones.

Silicone spray lubricants, plastic dressinggs, etc. can cause finishing problems. Try Googling “silicone fish eyes” for more details.

So, if I spread some silicone grease
around a scuffed patch of composite, then clean and sand the area as best I can, and finally apply a single layer glass patch with West 105/205, I’m going to see something later? My composite boats are thin, so I can even flex the patch in and out to see if it starts to pull loose in places.

I certianly hope…
…it isn’t a problem. I am thinking the old Armorall I use on the hatches and deck has silicone, and I KNOW the silicone grease I am using in the rudder cable housings is silicone…I would think the popular 303 product line might have silicone as well…as well as other newer plastic/rubber/vinyl preservatives, and maybe many boat waxes? I believe a lot of the waxes have PTFE teflon type additives…seems like that might be just as bad?

I’m hoping a good going over with denatured alcohol and a light fine wet sanding might prep it well enough. Or even acetone, although someone once told me it will damage or break down the composite plastic.

303 has no silicone
303 is not supposed to contain silicone; not sure about the ArmorAll.