Black Marks on Gelcoat wont come off

[jcwads]

Hi All

Looking for any tips here. I have some small areas of black marks on my gelcoat, just below where my camper covers are. I assume it must be dye from the covers?? I bought them new in Nov last year so maybe that? Or alternatively the black fender ropes rubbing on it.

Either way, its left black marks on the gelcoat that I cant remove with normal boatwash or elbow grease. Has anyone got any tips of something that may do away with stubborn marks that isnt too corrosive?

Cheers!

Jonathan

 

[Bav34]

These are worth a try ... sold under different names in most stores:

http://www.wilko.com/jml-products/jml-doktor-power-magic-eraser/invt/0278007

 

[Marine Reflections]

Feel positive you'll get some good tips; such as Acetone or Melamine sponges, but always a good idea to identify what the actual marks are before attacking, if indeed they are marks 'above the surface'.

For example, if it is indeed the dye from the cover, then possibly the dye is filling tiny pores.

Could be spider poop?
Metal marks from where the cover poppers have hit?

I've been dealing with 'black spots' for a friend recently who tried to remove without success, it was only by showing him close up macro pictures of the surface that he could see it was in fact tiny air holes within the gelcoat.

Any pictures possible?

 

[RichardS]

Give it a go with Peek or a similar metal polish and an old toothbrush. If that doesn't shift it it's not shiftable!

Richard

 

[pandroid]

Meguiars. Polish (45) will get pretty much all of this stuff off. If not, heavy duty oxidation remover (49) should do the rest.

 

[jcwads]

Thanks all. I'll give it a go with some polish and see if that does the trick

 

[MoodySabre]

Another vote for Magic Eraser.

 

[Yngmar]

Any mild abrasive will do. I use Barkeepers friend, just because it also removes rust stains at the same time due to having oxalic acid in it, so can be used for either. Afterwards you need to polish the area, as your mild abrasive treatment has roughened the gelcoat - if you don't, it'll attract dirt rapidly.

 

[QBhoy]

+1 on the meguires Polish and wax.
I get these marks all the time off the hood. I think any polish would take it off.

 

[Graham_Wright]

I used very fine stainless wire wool and oxalic acid.

 

[benchmark]

Your finger under a rag tip dipped in Acetone will remove the black marks before you can say Jackrobinson, wax the area afterwards to coat the now open gelcoat pores because the acetone will remove all previous wax.

 

[Caer Urfa]

'T' cut removes most marks from gel coat

 

[coveman]

'T' cut removes most marks from gel coat

Yes it will but only use the fibreglass version - not that used on cars (metal)

 

[jcwads]

Thanks all, some great advice, and i'll be sure to give it a go.

 

[johnalison]

I would attack the problem in the order: detergent, solvent, and then abrasive.

As a solvent, I would use a proprietory cleaner such as International gelcoat cleaner. For a solvent, I would go through the ones mentioned, maybe including simple ones like white spirit. For an abrasive, I would use Starbright Colour restorer polish first, and in any case, follow with wax.

 

[johnwest]

Farecla G3 ?

j