Bavaria Owners Forum

Member Forums => Bavaria Yacht Help! => Topic started by: falko on July 22 2024, 08:14

Title: black dots in gelcoat
Post by: falko on July 22 2024, 08:14
Hi, I have 2006 Bavaria 37. On deck I have noticed regions of tiny black dots in the gelcoat. They are only seen  from  up close. I've tried with 3M Medium (cut+polish) to no avail. Do you have any suggestions how to fix this?

Regards.
Title: Re: black dots in gelcoat
Post by: IslandAlchemy on July 22 2024, 08:26
This is a result of pressure washing the decks. Little holes get blown in the gelcoat, and water and dirt gets into them and go mouldy.

Get some mould & mildew spray. Spray it on and walk away. A day or two later it will be gone.
Title: Re: black dots in gelcoat
Post by: Ailatan on July 23 2024, 06:21
I used bleach with excellent results
Title: Re: black dots in gelcoat
Post by: falko on July 23 2024, 13:20
Thank you both. I'm on it.

Regards.
Title: Re: black dots in gelcoat
Post by: marioxp on July 23 2024, 18:30
it's the first time I've heard that pressure wash causes gelcoat damage!  Was it a particularly strong pressure wash?  I wash the deck with pressure wash a couple of times a year, always before polishing, I haven't noticed anything unusual.
Title: Re: black dots in gelcoat
Post by: tiger79 on July 23 2024, 19:02
Quote from: marioxp on July 23 2024, 18:30
it's the first time I've heard that pressure wash causes gelcoat damage!  Was it a particularly strong pressure wash?  I wash the deck with pressure wash a couple of times a year, always before polishing, I haven't noticed anything unusual.

I think it's more likely to be a case of micro bubbles in the gelcoat, which are then broken by pressure washing and form voids in which dirt and mould can loiter.  I had the same problem on some areas of the superstructure on a Hallberg-Rassy I owned.
Title: Re: black dots in gelcoat
Post by: Yngmar on July 23 2024, 20:12
Quote from: tiger79 on July 23 2024, 19:02
I think it's more likely to be a case of micro bubbles in the gelcoat, which are then broken by pressure washing and form voids in which dirt and mould can loiter.  I had the same problem on some areas of the superstructure on a Hallberg-Rassy I owned.

Yup, that's it, plus UV degradation of gelcoat over time contributes too. A Lagoon 38 S2 had it everywhere on deck except where it was shaded by the hardtop + tent.

You definitely want to have a care when pressure washing - a sufficiently strong pressure washer will take the gelcoat right off. Waterjet cutting is used to cut granite slabs :)
Title: Re: black dots in gelcoat
Post by: nightowle on July 23 2024, 22:48
I, too, have the same problem that has plagued our boat.  So, I'll have to try the mould removal method and see if that garners success.