Prop treatment Med - Update

[John100156]

Three pics from the Agua Fuerte bottle
I didn't study chemistry at school so I can't comment.

OK In your second image it shows this is 20% chlorohydric acid, which is simply another name for hydrochloric acid, so that's what Agua Fuerte is 20% inhibited hydrochloric acid....! Where's Vics when you need him....

 

[Hurricane]

Did you read all the Spanish then John?

BTW - do you really want to see a pic of JW before the pressure wash?

 

[Medskipper]

Mike, you are very welcome to polish my props and rudders and finish them with A Glaze if you don't want to wait until next year to see if it works. Boat is being lifted in two weeks.

 

[Hurricane]

Mike, you are very welcome to polish my props and rudders and finish them with A Glaze if you don't want to wait until next year to see if it works. Boat is being lifted in two weeks.

Ha Ha Ha
But we will probably be in Mallorca - enjoying the sun while you sweat on the boat - done ours for this year.

Just because I already have the image in Photobucket, here's a pic of the shine that young Chris got using the A Glaze this year.

 

[GrahamHR]

OK In your second image it shows this is 20% chlorohydric acid, which is simply another name for hydrochloric acid, so that's what Agua Fuerte is 20% inhibited hydrochloric acid....! Where's Vics when you need him....

"Inhibited" hydrochloric acid; what is that, inhibited from what undesired reaction ? I thought hydrochloric acid was just hydrogen chloride dissolved in water.

Regardless, 34% + hydrochloric acid is easily available in the UK, on Ebay for instance.

 

[John100156]

The word "inhibited HCl" is usually used to indicate hydrochloric acid with an acid corrosion inhibitor.

Hydrochloric acid is usually used as diluted in water, particularly 3 to 10% which varies by the fouling characteristics and material in the system.

Acid corrosion inhibitor means organic compound which adsorbs metal surface to protect metal from acid atmosphere. It is commercially available and typically composed of several mixture of organic amines, imines, and/or thioureas, and so on.

There are a lot of products from chemical companies in the market and several types depend on the applications such as hydrochloric acid, sulfuric acid, organic acids, and so on.

The inhibited acid is at times heated usually up to 60 °C to facilitate the dissolving reaction between scale and the acids.

You should be careful to apply these acids of course, because hydrochloric acid, even inhibited, could attack some materials, like highly mechanically arranged devices and could lead to serious damage like cracking or partially detrimental corrosion. Especially for austenitic stainless steel, when it is finely modified.

When we used it in heat exchangers in cooling systems in the 80's we purchased it at 32% Inhibited adding it into the sumps of cooling towers all over the UK, Amsterdam and Belgium. Worked a treat.

So we need to be careful what we apply it to, un-inhibited it can adversely affect certain metals, but we then drop the boat back into sea water so I doubt it would adversely affect our props and shafts as Mike is using it.

Mike - yes I would truly like to see the pre-scrub condition, just to compare it with Trilux which as you know, is OK pottering around the lagoon and whilst sitting on berth but soon washes off, so I reckon regular (good value) lift and scrubs is the order of the day in SCM.

 

[John100156]

Just Googled this:
To make an inhibited HCl solution according to ASTM, add 500 ml HCl to 500 ml water, and dissolve in 5 g of antimony trioxide, and 5 g of stannous chloride. Ta-da!

Goodness knows what that mix will do - Where are all our chemists when you need them????

Like Mike - I have been using Agua Fuerte for many years, in Feb 2011, I had my F43 lifted in Sotogrande I think it was, I could not get her lifted in Duquesa and without asking, they brought 6 x 1L bottles and used several without adding anything to the cost, I had used it on my T34 before so was quite happy for them to do so, great stuff.

 

[Andrew M]

20%, ahhh, so that's why your Spanish Prop Water is so much more effective than our English Prop Water........It's more than twice the strength. The generally available builders merchant masonry cleaners I tried were about 8% hydrochloric.

Will look to source something stronger next winter, so will look up Woburn Chem , I'm up in that area every week for work anyway. Good to know I can go up to 20% though, without any apparent ill effects.

Thanks for the bottle pic and info.

 

[Andrew M]

Just spoken to Woburn Chems, excellent lead, thanks. Yep, looks like they can supply 20% Hydrocholric, starting off in 25ltrs but may be able to do less, they will let me know. But I'm sure me and a few mates would be able to split that between us anyway.
Great, thanks.

 

[Hurricane]

Mike - yes I would truly like to see the pre-scrub condition, just to compare it with Trilux which as you know, is OK pottering around the lagoon and whilst sitting on berth but soon washes off, so I reckon regular (good value) lift and scrubs is the order of the day in SCM.

Here you go John

I think it shows that if you don't paint the metalwork, you definitely need to lift and scrub a couple of times during the year if you are going to keep a boat in SC.
That said, it is very cheap to lift and scrub - IIRC about 160 euros for JW but most of us get a free lift and scrub each year anyway.

So from the top pic to this one in about 40 mins (inc the trim tabs and the rest of the boat not shown in this pic)

And one more pic for completeness sake.
Taken after 3 days in the boatyard - waiting for relaunch

 

[Portofino]

Just to illustrate other Med areas here,s SoF -you get a like of worm that gives a rough concrete texture .its this we can scape off ,diving /snorkelling -we don,t need to lift to shift weed .

After 12/12 -it looks like a white cement layer or Worse de zincified props
You can also see how tge wash "cleans" the rudders and the hub ( not the blade tips ) -see the brass areas
Q anybody know why props clean up like this ? -hub shines up 1st ?

Mid season -you can see a rough surface -which scrapes off

HCL acid cleans it up

 

[John100156]

.....Here you go John

I think it shows that if you don't paint the metalwork, you definitely need to lift and scrub a couple of times during the year if you are going to keep a boat in SC.....

Thanks Mike - last lift on CR just before Xmas as below and pretty much backs-up what you are saying, waste of time using anything, you may just as well lift, acid scrub and polish the props and metalwork. Why waste money on expensive AF if it doesn't work, at least your way it seems to make it easier to remove the growth - think I may try it out next lift:-

 

[grumpy_o_g]

...Q anybody know why props clean up like this ? -hub shines up 1st ?

I suspect it's because the tips suffer the most from cavitation and ventilation, even if only occasionally - causing small pitting in the surface making them a better surface to key to as well as rougher surface to shine up. I've seen similar sort of thing on aircraft props

 

[wellf100]

at the risk of boring people banging on about AquaCote, has anyone tried or considered their Propcote product? https://www.aqua-cote.com/pages/prop-preparation-maintenance. I've no idea if it's does stick as well as suggested and haven't seen any reviews but maybe worth considering?

 

[Whitelighter]

at the risk of boring people banging on about AquaCote, has anyone tried or considered their Propcote product? https://www.aqua-cote.com/pages/prop-preparation-maintenance. I've no idea if it's does stick as well as suggested and haven't seen any reviews but maybe worth considering?

Ive got a kit, and I might apply it next year. I ran out of time this year as the application instructions are onerously precise

 

[wellf100]

i see what you mean!

the only evidence of performance i've seen is this tweet from Harry Metcalf https://twitter.com/harrym_evo/status/583179967003025408 which sings it's praise. A bit suprised it's not been tried (and reported on) by more people though given the hassle that prop fouling seems to cause going by this thread!.

 

[PowerYachtBlog]

I think that much growth can also be because St.Carles by the video Hurricane posted looks very inside a canal (so boats hardly get any current).
Even in the same marina I am in if I am located more inside I get more growth then my usual pontoon.

 

[Hurricane]

I think that much growth can also be because St.Carles by the video Hurricane posted looks very inside a canal (so boats hardly get any current).
Even in the same marina I am in if I am located more inside I get more growth then my usual pontoon.

You are correct but it isn't because of any inside canal.
We are located on the edge of the Ebro Delta - massive flat fertile land that sticks out into the Med.
Over the years, the farmers on that land have created water irrigation channels so that they can flood their fields to create paddy fields and grow rice - especially good in the local Paellas.
IMO, it is the fertile water flowing off the delta that also fertilises the water in the two lagoons that are formed by the delta.
SCM is located just behind one of those lagoons.
Once you accept that the water in the marina is very fertile and susceptible to marine growth, there are many benefits. Lots of interesting wildlife live on the delta (flamingos and many different species of birds) but also great shellfish (particularly mussels and oysters) are grown on wooden frames out in the lagoon. Great supply for the local restaurants.

Here are a couple of pics in case you find this kind of thing interesting.

This one shows the paddy fields on the delta - the marina is in the bottom right corner of the pic.

And this one shows the lagoon - the mussel beds (frames) can be seen in the other side the marina sea wall.

 

[Outforaduck]

Used Agua Fuerta in the toilets on my old catamaran following advice from the ex owner. Used to 'dump' a litre into each head and leave to do its work clearing the somewhat soiled pipe work. Seemed to work.

In terms of hull and props I met a nice French man (Bernard) who swore by his 'waveblade' to clean everything below waterline on his Lagoon 39. I might try one if I can get to warmer water in the future.

 

[PEJ]

This thread approaches in to the edge of my expertise which is swimming pool chemicals. I use 28% hydrochloride acid to adjust the pH of water. This is strong stuff! Drop it neat on your paving slabs and watch them fizz!

We also use a very niche product to clean the metal electrolyte cells of salt chlorinators which claims to much more gentle on the metal. But dip a calcium encrusted cell in this stuff and fizz! The calcium is gone in seconds. It contains phosphoric acid. If anyone wants to give it a try let me know and I'll get you some. Here is the manufacturer's blurb.

http://www.lo-chlor.co.uk/pool-chemicals-2/clean-cell-plus/

It is much easier to handle than 28% hyrdrochloric, I use it to clean my shower glass.