Blotches on deck - can you identify - SailNet Community
 3Likes
Reply
 
LinkBack Thread Tools
post #1 of 16 Old 12-30-2013 Thread Starter
Member
 
Join Date: Aug 2011
Location: Southeast Florida
Posts: 71
Thanks: 0
Thanked 0 Times in 0 Posts
Rep Power: 4
 
Blotches on deck - can you identify

I recently acquired an 1989 Catalina. Since buying it, I had the deck and hull waxed, and have washed it down several times. Earlier this week after a rain shower the blotches and stains appeared. Some were pinkish others were gray/black. I hosed them down but they persisted. Next day they were gone. Can anyone help me with this mystery?
Attached Thumbnails
cabin top.jpg   pink blotch.jpg   port aft.jpg  

Last edited by armandolio; 12-30-2013 at 10:59 PM.
armandolio is offline  
Quote Quick Reply Share with Facebook
Sponsored Links
Advertisement
 
post #2 of 16 Old 12-30-2013
Senior Member
 
RichH's Avatar
 
Join Date: Jul 2000
Location: Pennsylvania
Posts: 3,444
Thanks: 24
Thanked 149 Times in 138 Posts
Rep Power: 16
 
Re: Blotches on deck - can you identify

I have the same thing on my boat. Im currently in SE Florida awaiting the Xmas trade winds to die down a bit before proceeding further south.

My speculation/guess is that this is airborne bacteria, probably coming from Africa, and is using the wax on boats as its nutrient source, as unwaxed boats dont seem to have the problem. Also interesting was that this 'blush' when off central and northern Florida (NE trade winds) was 'reddish', in SE Florida (easterlies and southeasterlies) its more greyish. If it was dust from the Sahara it would be more 'yellowish', so my guess its probably bacteria as its quickly removed (bleached) by a wash with diluted oxalic acid solution. The recent sunrises and sunsets here have also been 'brilliantly yellow' which is unusual.
RichH is offline  
Quote Quick Reply Share with Facebook
post #3 of 16 Old 12-30-2013 Thread Starter
Member
 
Join Date: Aug 2011
Location: Southeast Florida
Posts: 71
Thanks: 0
Thanked 0 Times in 0 Posts
Rep Power: 4
 
Re: Blotches on deck - can you identify

RichH,
Interesting theory. That never occurred to me.
armandolio is offline  
Quote Quick Reply Share with Facebook
post #4 of 16 Old 12-31-2013
Senior Member
 
gamayun's Avatar
 
Join Date: Aug 2009
Location: San Francisco
Posts: 554
Thanks: 17
Thanked 27 Times in 27 Posts
Rep Power: 6
 
Re: Blotches on deck - can you identify

Are the blotches in areas where people with bare legs have sat? Might be the chemicals from sunscreen.


To view links or images in signatures your post count must be 10 or greater. You currently have 0 posts.

s/v Kynntana
Freedom 38
gamayun is offline  
Quote Quick Reply Share with Facebook
post #5 of 16 Old 12-31-2013
Senior Member
 
Join Date: Aug 2013
Location: Sweden
Posts: 284
Thanks: 7
Thanked 18 Times in 18 Posts
Rep Power: 2
 
Re: Blotches on deck - can you identify

You had the boat waxed? Deck and wax doesn't go well together:
1) difficult to clean as the anti-slip on the deck works against cleaning. Not to speak about removing old oxide and even the surface with rubbing etc, this is just not possible if one wants the anti-slip to remain.
=> deck surface will not be really cleaned.
2) wax makes the surface more slippery (there are special anti-slip waxes, but in my experience they are not good in any respect).
3) decks are usually horisontal. Moisture and dirt doesn't just drip away, but stays longer, some of it forever it seems.

The blotches you see can be any kind of dirt that was not really removed before waxing, combined with water / moisture. Can also mainly be just increased moisture in the wax. Disappears when the surface has dried. Comes back when new water is applied.

If you can't live with it (I would) then you have to completely remove the wax. Then you have to decide if you want new wax or not.

An alterntive solution is to paint the deck. Up-side is that there is no wax, no such issues - and you get a fresh deck in the color you prefer. Downside is that the deck need to be repainted now and then.

/J
Jaramaz is offline  
Quote Quick Reply Share with Facebook
post #6 of 16 Old 12-31-2013 Thread Starter
Member
 
Join Date: Aug 2011
Location: Southeast Florida
Posts: 71
Thanks: 0
Thanked 0 Times in 0 Posts
Rep Power: 4
 
Re: Blotches on deck - can you identify

I misspoke. The waxing was of the hull and cabin top, the horizontal parts.

Jaramaz - while your explanation of it being dirt exposed by moisture makes sense, the mystery remains. It was not exposed during washing of the boat, only after it rained. Then they disappeared.
armandolio is offline  
Quote Quick Reply Share with Facebook
post #7 of 16 Old 12-31-2013
snake charmer, cat herder
 
zeehag's Avatar
 
Join Date: Nov 2008
Location: refitting a formosa in exotic tropical locations....
Posts: 1,796
Thanks: 8
Thanked 28 Times in 28 Posts
Rep Power: 7
 
Re: Blotches on deck - can you identify

looks like you polished thru the gelcoat to almost fiberglass...stop polishing. prep f or paint or gelcoating, which is prohibitively priced. is why folks paint their old fg boats.


To view links or images in signatures your post count must be 10 or greater. You currently have 0 posts.

formosa 41, cruising tropics


To view links or images in signatures your post count must be 10 or greater. You currently have 0 posts.


To view links or images in signatures your post count must be 10 or greater. You currently have 0 posts.
zeehag is offline  
Quote Quick Reply Share with Facebook
post #8 of 16 Old 12-31-2013
Senior Member
 
Join Date: Jul 2008
Location: 34.25n 119.27w
Posts: 488
Thanks: 1
Thanked 5 Times in 4 Posts
Rep Power: 7
 
Re: Blotches on deck - can you identify

Are you by any chance downwind of a boatyard? Sanding dust from copper bottom paint turns decks funny colors after exposure to moisture from rain or dew.

BTW, the best (and cheapest) product for removing stains from gelcoat that I have ever tried is Lysol toilet bowl cleaner in the squeeze bottle. Be very careful around aluminum though.
davidpm likes this.
SJ34 is offline  
Quote Quick Reply Share with Facebook
post #9 of 16 Old 12-31-2013 Thread Starter
Member
 
Join Date: Aug 2011
Location: Southeast Florida
Posts: 71
Thanks: 0
Thanked 0 Times in 0 Posts
Rep Power: 4
 
Re: Blotches on deck - can you identify

No boatyard anywhere near. I am Dinner Key Marina in Miami.
armandolio is offline  
Quote Quick Reply Share with Facebook
post #10 of 16 Old 12-31-2013
Old enough to know better
 
Join Date: Dec 2006
Location: Beacon, NY
Posts: 3,074
Thanks: 19
Thanked 128 Times in 124 Posts
Rep Power: 9
 
Re: Blotches on deck - can you identify

Quote:
Originally Posted by zeehag View Post
looks like you polished thru the gelcoat to almost fiberglass...stop polishing. prep f or paint or gelcoating, which is prohibitively priced. is why folks paint their old fg boats.
I think we may have a winner here. Especially if you "had it waxed" as they normally use very high speed equipment and if they had a new kid they may have burned or took off to much gel coat. Welcome to the world of it is better to break it yourself rather than to pay someone else to break it for you, I mean do it your self, your not supposed to break things are you?
zeehag and Dave_E like this.
miatapaul is offline  
Quote Quick Reply Share with Facebook
Reply

Quick Reply
Message:
Options

By choosing to post the reply above you agree to the rules you agreed to when joining Sailnet.
Click Here to view those rules.

Register Now



In order to be able to post messages on the SailNet Community forums, you must first register.
Please enter your desired user name, your email address and other required details in the form below.
Please note: After entering 3 characters a list of Usernames already in use will appear and the list will disappear once a valid Username is entered.


User Name:
Password
Please enter a password for your user account. Note that passwords are case-sensitive.

Password:


Confirm Password:
Email Address
Please enter a valid email address for yourself.

Email Address:
OR

Log-in









Human Verification

In order to verify that you are a human and not a spam bot, please enter the answer into the following box below based on the instructions contained in the graphic.




Currently Active Users Viewing This Thread: 1 (0 members and 1 guests)
 
Thread Tools
Show Printable Version Show Printable Version
Email this Page Email this Page



Similar Threads
Thread Thread Starter Forum Replies Last Post
Help Identify Deck Plate / Inspection Port aloneinthewoods Gear & Maintenance 3 03-25-2013 05:06 PM
Seeking opinions for deck and hull-deck joint repair gregor1234 Gear & Maintenance 8 04-25-2012 11:10 PM
Split deck cap and leaking hull/deck joint alaskaboy Gear & Maintenance 2 01-04-2008 09:25 PM
through deck coaxial cable-what wonderful suprises await me, my deck and my drill? bwu Catalina 1 11-20-2006 01:06 PM
wet deck - repairs to foam cored deck jheaton Gear & Maintenance 1 04-22-2002 07:17 PM

Posting Rules  
You may post new threads
You may post replies
You may not post attachments
You may not edit your posts

BB code is On
Smilies are On
[IMG] code is On
HTML code is On
Trackbacks are On
Pingbacks are On
Refbacks are On

 
For the best viewing experience please update your browser to Google Chrome