cleaning 30 year old gunk of fiberglass

[CaseyJones]

There are some teak rails along the top of my Tanzer 22's hull.. We decided they needed to be removed, sanded and refinished.. I removed them, and have about 5 days until the next forecase rainfall before I need to either put the wood back on, or tape up the holes so water doesn't get in the V-berth..

Anyways, after taking them off of course there is a lot of VILE black gunk undernearth the wood.. the fiberglass gelcoat surface under the gunk seems to be in good shape, so I assume this is just 30 year old adhesive or silicone sealant..

but how to I clean it off??


I scraped off what I could with a putty knife.. Tried a rag and some thinner.. no go.. tried a rag and some fiberglass cleaner.. no go.. scrubbed at it for a good 15 minutes (albeit with a rag)

any suggestions? I was thinking solvent and a scouring pad.. but I don't want to scratch the gelcoat, which conseidering the age of the boat is in pretty pristine condition..

what's the best way to get this crud off my deck?

[SVCarolena]

Try heat and a scraper first. If that doesn't work, try acetone. If that doesn't work, then you may want to try very fine grit wet/dry sandpaper. In my experience, the acetone will remove the vast majority of tacky adhesives (just wear gloves, avoid fumes and stay away from any sparks or open flames). However, it doesn't remove some caulking (like cured polysulfide or silicone). I had to reseal some deck hardware and wound up using the wet/dry sand paper to remove the residue. Assuming the area will be recovered when you replace the parts, so too should any sanding of the gel coat.

[CaseyJones]

acetone didn't do squat (but i had already gotten most of the loose stuff off w/ a plastic putty knife)

sand paper took it all off in a cinch .. i had it all cleaned and the holes taped up inside of 30 minutes

[SVCarolena]

Glad to hear it!

[midnightsailor]

Here is a solvent that might do the trick. It is great for many things. for instance. it will clean up uncured polyester resin from hands ,tools etc. and will not burn small cuts on the hands like acetone always does.. removes creasote from hulls, fenders etc. cleans up epoxy resin as well. It will clean lifelines, fenders, cowl vents and winch holders like new, removes engine exhaust stains, cleans hands when working with silicone and polysulfide, great for all kinds of grease and oil such as engine cleaning, parts etc. removes waterline scum(just don't use it on painted waterlines ie:boot top) removes pencil and crayon from anything, revitalizes old formica, removes smudges from stainless steel and chrome. and countless other things. One caveat DO NOT USE ON: ABS PLASTICS SUCH AS PORTHOLE RIMS AND SUCH, OR ON LEXAN(burt ok on plexiglass) and keep away from varnish or paint, except as a prefinish wipedown which it is also excellent for. What is it? BRUSH CLEANER !. Not to be confused with paint thinnersmineral spirits or turpentine. Brush cleaner is soluble in fresh or salt water, so if onthe can it instructs you to rinse your brushes afterward in fresh water , you know you got the right stuff...and, oh yea, it is also great for revitalizing old, stiff, dried out paint brushes. It is combustible so use plenty of ventalation and keep away from sorces of ignition.
Rick, SV ARTEMIS