Lemon juice

Oct 2, 2008
3,807
Pearson/ 530 Strafford, NH
Hi all,

Our rafting mate was spraying his boat with lemon juice and the ICW Stain was running off. He mixed his half/half. We went shopping for ourselves and mixed it 50/50 in a garden sprayer. The brown stain came off without scrubbing, no gloves or respiratory protection needed.

The beauty was we got the juice at the Dollar Tree for a $1 a bottle.

All U Get
 

Kermit

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Jul 31, 2010
5,657
AquaCat 12.5 17342 Wateree Lake, SC
Are you serious, Clark?
I'm on my way to the dollar tree to get a roll of wrapping paper. I might just have to get some lemon juice. Thanks for the tip. And Merry Christmas!
 
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Mar 20, 2012
3,983
Cal 34-III, MacGregor 25 Salem, Oregon
:confused:

The acid in lemons is a carboxilic acid... as is oxalic acid etc. All carboxilic acids work well on tannins. But acid is not all the same... muriatic (HCl) will attack metals... so dont use it on metals. Sulfuric will attack organic material so keep it off cloth and skin...
muriatic and sulfuric will dissolve the tannin stains also, very quickly, which is due mostly to the strength of them vs the lemon juice or vinegar....
nylon can be damaged by exposure to moderate strength acids, so be aware of what may be made of nylon on the boat, and try to keep it protected.

I use acids quite often for different things... muriatic, sulfuric and mostly hydrofluoric, and in the strengths I use them, they will all damage your clothing and skin.... different acids do work differently on not organic objects.
getting any industrial strength acid on your hands and not washed off before the pain starts, the acid will soften your fingernails to the point that the fingernail gets a yellowish hue and begins to turn into a gel, and your fingerprints will be eaten from your fingers..... and then weeks of pain and healing with chance of permanent nerve loss..... but so far my fingerprints have always grown back....
 
Feb 26, 2004
22,759
Catalina 34 224 Maple Bay, BC, Canada
but so far my fingerprints have always grown back....
There goes your personal security blanket! :)

Tannin stains, we like to call them our "boat mustache" are caused by "stuff" in the water. I've been using FSR for years, and lemon juice and also ketchup are also reported to work for a more cost effective solution. :)

My experience is that whatever you use to remove the stain, wax it immediately or else it will grow back. Why? 'Cuz whatever you use will open up the microscopic "pores" in the gelcoat and the stains will start all over again.

We FSR'd our bow before we left on our six week trip from SF to Vancouver Island last summer, and waxed right after. The bow is still clean after 850 nm.

When I'd do that, even in SF Bay without waxing, within a month I'd get the stain back.

Remove and treat is better than just removal.
 
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Kermit

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Jul 31, 2010
5,657
AquaCat 12.5 17342 Wateree Lake, SC
With all of the technical-sounding replies, here's the bottom line question: Is lemon juice safe and effective? (I guess it's effective since All U Get reported that it works for him.) So maybe I should just ask if it's safe and a good idea?
 
Jan 1, 2006
7,039
Slickcraft 26 Sailfish
:confused:

The acid in lemons is a carboxilic acid... as is oxalic acid etc. All carboxilic acids work well on tannins. But acid is not all the same... muriatic (HCl) will attack metals... so dont use it on metals. Sulfuric will attack organic material so keep it off cloth and skin...
If I remember granger is a Professor of Chemistry. So I defer to him. Anyway, I spent most of my time in Chemistry class with my cheek firmly planted on the desk with drool running out of my mouth. I do NOT want to revisit pKa discussions....
 
Sep 30, 2013
3,538
1988 Catalina 22 North Florida
I spent most of my time in Chemistry class with my cheek firmly planted on the desk with drool running out of my mouth.

LMAO ... :laugh: You're not alone my friend, it was the only thing I ever failed, other than winning the affections of the girl who sat in front of me. She let me cheat off of her, but it wasn't enough. In more ways than one.

Lemon juice! That's an awesome tip, @All U Get, I will definitely try it. I currently use the bargain-brand toilet bowl cleaner "The Works", but when the boat is in the water, I would feel a lot better using something natural.
 
Jul 7, 2004
8,402
Hunter 30T Cheney, KS
Does the lemon juice stain the bottom paint as it runs down? That's the reason I use toilet bowl cleaner gel on the waterline stain. It stays put until I wipe it off. Very cheap in the store brands.
 
Jun 2, 2007
403
Beneteau First 375 Slidell, LA
@centerline what are you using HF for? That is some NASTY stuff.
I'm curious, too. HF is used in a process unit at the refinery where I used to work, to produce high-octane gasoline. Easily the worst industrial chemical I have ever come across, with VERY elaborate precautions for handling.
 

Gene

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Sep 17, 2009
9
Precision 23 Moraine
I'm in fresh water but, I've found that Turtle Wax Bug and Tar Remover works wonderfully. I just spray it on wait a minute and wipe it off. There's very little runoff and it seems to be easier to clean with subsequent applications. It's inexpensive (WalMart) and comes in a spray bottle. I like the lemon juice idea, as well. How would it work on bird/spider stains on the topside? The Turtle Wax would make the deck slippery, I'm sure.
 
Oct 22, 2014
20,989
CAL 35 Cruiser #21 moored EVERETT WA
FSR - Fiberglass Stain Remover - is a 4.5 % solution of Oxalic Acid. Comes in a gel formula.
 
Oct 2, 2008
3,807
Pearson/ 530 Strafford, NH
The juice didn't stain our white bottom paint. We're in the water so very friendly to the fish and I can use the leftovers in my rum drinks.

All U Get
 
Jan 19, 2010
12,362
Hobie 16 & Rhodes 22 Skeeter Charleston
Lemon juice! That's an awesome tip, @All U Get l would feel a lot better using something natural.
Kermit asked if it safe... for sure! And vinegar would be a good choice too. Also natural and low health risk.

I would advise against hydro floric acid (HF). HF can attack window glass ( it is how they make frosted glass) and it can attack polyester and amide bonds (resin) and it can do a real number on you lung tissue if you inhale the fumes. HCl is okay if dilute and in a Ventalated space and keep it off of metals