Gelcoat Cleaning

[svenskflicka]

Hey everyone, I have some dried greasy gunk on my hull, any tips on cleaning it off?

What's the general procedure for getting the gelcoat looking nice?

What tools should I use?

Thanks!

[a64pilot]

Be a little more specific.
For removing gelcoat stains from tannic water and algae etc. I like Mary Kate on and off, which is some kind of very strong acid, do not get it on your skin.
Once cleaned, many will lightly wet sand and polish and wax, and it can look gorgeous, but it’s a lot of work and has to be kept up with.
There are also sealants to seal the gel coat and they are easy and look great, but my experience with them is that after a year or so they don’t look so good, and it’s tough to get that stuff off.

[Stu Jackson]

https://forums.sailboatowners.com/in...ff-wax.117266/

[svenskflicka]

Originally Posted by a64pilot

Be a little more specific.
For removing gelcoat stains from tannic water and algae etc. I like Mary Kate on and off, which is some kind of very strong acid, do not get it on your skin.
Once cleaned, many will lightly wet sand and polish and wax, and it can look gorgeous, but it’s a lot of work and has to be kept up with.
There are also sealants to seal the gel coat and they are easy and look great, but my experience with them is that after a year or so they don’t look so good, and it’s tough to get that stuff off.

Thanks for the reply it's not a stain, but physical gunk ON the hull.

[a64pilot]

What the gunk consists of will determine what is used to clean it off.
I just had a bottom job done and had dried algae slime just above the boot stripe, acid wash took it off pretty easily for instance, but marks on the hull from an old fender acid wash won’t do a thing to that.

[svenskflicka]

Originally Posted by a64pilot

What the gunk consists of will determine what is used to clean it off.
I just had a bottom job done and had dried algae slime just above the boot stripe, acid wash took it off pretty easily for instance, but marks on the hull from an old fender acid wash won’t do a thing to that.

I'm not sure what it is, it looks like dried grease, but thick. I dont have a photo.

[a64pilot]

If its grease like, I’d start by trying mineral spirits (paint thinner) and work my way towards acetone.
I’m thinking solvents as opposed to soaps, but trying a good detergent won’t hurt.

Acetone will likely dissolve any vinyl lettering or stripes if you have any, but has no effect on fiberglass, protect yourself from breathing its vapors though.
The mineral spirits except from being flammable is pretty tame stuff.