Oxalic acid, soap and Vinegar or compound-polish and wax

[Jamesuk]

Hi,

Here in Saint Lucia, Locals will say they use vinegar on the hull but I have a sneaky suspicion they use Oxalic acid and wont tell the owners because as I have read in other forums the word acid scares people off. Tho, the general consensus is that oxalic acid is great on the fibreglass just not on the hands.

Using Oxalic acid actually concerns me a little on blue hulls but I recall every season at sunsail they would use oxalic acid on the White top sides to clean them.

Having worked on private yachts we would usually compound a hull if it was bad or simply polish then wax the hull to keep it looking great. So the question I have is which is better.

Washing a boat down with soap with Vinegar then using compound/polish/wax or going for the quick option washing the hulls with Oxalic acid.

I ask this question as I have someone with a 8 month old yacht having just crossed the Atlantic and I would not want the locals putting an acid on a brand new yacht but I thought I would ask the collective group of YBW for advice

Cheers

PS (Side point: I have in the past used Alkaline and Oxalic acid on the teak deak on large megayachts, Some people have said that Feadship say "if you do use it in the first 5 years they will vod all warranty's on drainage and fittings that are at deck level".)

 

[William_H]

Hull cleaning

Of course much depends on what the stain on the hull is but I have found the brown stain my hull gets near the water line is removed easily with oxalic acid but then again it is also removed with lemon juice so I am sure vinegar would do the same thing.
I imagine or assume that washing with fresh water will eliminate any remaining acid so you could then wax or polish as you wish. good luck olewill

 

[ostell]

But then vinegar and lemon juice are also acids, acetic and citric. Just tell them that oxalic acid is rhubarb juice.

 

[SlimRick]

But then vinegar and lemon juice are also acids, acetic and citric. Just tell them that oxalic acid is rhubarb juice.

It is? Great - just off to make a smoothie.

 

[ostell]

From Wikipedia: "Rhubarb leaves contain about 0.5% oxalic acid"

Not recommended for consumption, though I have splashed myself accidentally and it does taste like rhubarb!

 

[Jamesuk]

Thanks for the advice,

The question i had was for the salt deposits that build up more noticeably on a blue hull.

 

[Stu Jackson]

Thanks for the advice,

The question i had was for the salt deposits that build up more noticeably on a blue hull.

Doesn't soap and water do the trick?

O acid I've found is only needed for what I call the brown "mustache" on the bow. Then I clean with soap & water and wax over with a carnuba wax.

 

[Bosun Higgs]

Hi,

Here in Saint Lucia, Locals will say they use vinegar on the hull but I have a sneaky suspicion they use Oxalic acid and wont tell the owners because as I have read in other forums the word acid scares people off. Tho, the general consensus is that oxalic acid is great on the fibreglass just not on the hands.

Using Oxalic acid actually concerns me a little on blue hulls but I recall every season at sunsail they would use oxalic acid on the White top sides to clean them.

Having worked on private yachts we would usually compound a hull if it was bad or simply polish then wax the hull to keep it looking great. So the question I have is which is better.

Washing a boat down with soap with Vinegar then using compound/polish/wax or going for the quick option washing the hulls with Oxalic acid.

I ask this question as I have someone with a 8 month old yacht having just crossed the Atlantic and I would not want the locals putting an acid on a brand new yacht but I thought I would ask the collective group of YBW for advice

Cheers

PS (Side point: I have in the past used Alkaline and Oxalic acid on the teak deak on large megayachts, Some people have said that Feadship say "if you do use it in the first 5 years they will vod all warranty's on drainage and fittings that are at deck level".)

1/ Vinegar is an acid - acetic acid
2/ oxalic is an oxidising agent and effectively bleaches the surface. It doesnt remove oxidised gel coat - you compound to remove the top surface of the gel coat and get a shine
3/ there is no point in using an alkai and an acid together - one will neutralise or at least greatly weaken the other depending on proportions in the mix
4/ alkaline is an adjective not a noun.
5/ vinegar is useful for cleaning glass and other shiny surfaces - like other mild acids, it cuts through grease. Try lemon juice or even that Ozzie cleaner based on fruit. But vinegar wont bleach off the brown waterline stain.

 

[ccscott49]

1/ Vinegar is an acid - acetic acid
2/ oxalic is an oxidising agent and effectively bleaches the surface. It doesnt remove oxidised gel coat - you compound to remove the top surface of the gel coat and get a shine
3/ there is no point in using an alkai and an acid together - one will neutralise or at least greatly weaken the other depending on proportions in the mix
4/ alkaline is an adjective not a noun.
5/ vinegar is useful for cleaning glass and other shiny surfaces - like other mild acids, it cuts through grease. Try lemon juice or even that Ozzie cleaner based on fruit. But vinegar wont bleach off the brown waterline stain.

You use the alkali cleaner first, then the oxalic "brightener" second, not together.

 

[VicS]

2/ oxalic is an oxidising agent and effectively bleaches the surface.

Oh no it isn't! .... A reducing agent if anything


It is an acid... it is a stronger acid than acetic acid so will remove carbonate scale bound deposits more quickly ... it can also be made up as a more concentrated solution than the acetic acid in vinegar.

Citric acid is a slightly stronger acid than acetic acid. So perhaps more effective than vinegar, esp if made more concentrated, but not as effective as oxalic acid

For what they are worth pKa values are oxalic acid 1.27, citric acid 3.13, acetic acid 4.76