Propspeed

[Chris H]

IMO none of the coatings stick to the props.
Great if you don't use the boat but there is just too much energy being dissipated down there.
My solution is spend your time polishing the props etc.
Then lift the boat and do a quick acid wash.
I can get ours acid washed in the time that the rest of the boat gets pressure washed.

Before

View attachment 137702

And about 45 minutes later after a pressure wash and acid wash.

View attachment 137703

In Spain, we buy the acid from the local supermarkets

I wasn’t aware you could acid clean yourself, what’s the stuff called and what do you do with the run off ?

 

[EugeneR]

We had Propspeed professionally applied by a reputable yard on the Hamble. It did not work and, in a few weeks only, it looked as if nothing was applied i.e. did not do what it promised on the brochure at the time. I'd avoid.

 

[Portofino]

I wasn’t aware you could acid clean yourself, what’s the stuff called and what do you do with the run off ?

It’s just ( x% ) hydrochloric acid ,The yards sell it in L or 5 L containers .
Jet wash the yard does that .You just paint it on with a brush + agitate it gently and it removes the remaining calcium based growth on the metal work in about 10 mins .
Yards have a special drainage system to collect the poison AF that litters the yard floor , a kinda sump .The acid “ run off “ just goes into the mix in there .
Thats partially why the lift out / lift in fee feels a bit toppy …..there’s the environmental clean up kit to fund as well as the crane / lift and other other heads .


see the little pot + brush .The streaks of acid on the metal work .^ Need a final rinse with water hose .



^ Mate working on them ( I’d bust a shoulder that year on my snow board ) They get a free boys trip to Monaco BTW .


But without any protection ^^^ this is what inevitably happens , the accretions start to come back and you end up diving / cleaning all over .

 

[BartW]

I use Velox + for several years, and very pleased with the result
have been advised that preparation and correct application is crucial to a good result.

 

[Hurricane]

I wasn’t aware you could acid clean yourself, what’s the stuff called and what do you do with the run off ?

This is the stuff that we use:-



In Spain, it is usually called Agua Fuerte (literally translated as "Strong Water").
We buy it in the local supermarkets.
It dissolves anything calcium based so barnacles stand no chance.

Over the years, we have developed a technique which doesn't really use a lot so it gets diluted before it hits the concrete of the boatyard.
When the boat is lifted, the boatyard guys first give the props, shafts, rudders and trim tabs a quick blast to get the worst off.



After the pressure wash, there is still a layer of barnacles on the surface so "in we go".



It is amazing just how much is still left after the pressure wash - that photo doesn't show it but there is a good millimetre of barnacles left on.
Over the years, we have learned that just squirting it with Agua Fuerte (acid) doesn't do much.
You have to keep the contact of the acid to the metalwork moving.
To that end, all we use is a standard 3" paint brush.
We decant the acid into old yogurt pots and dip the paint brushes into the pots.
Then, using a "swirling" motion, gently rub the metalwork with the paint brushes.
Then dip and swirl again.
It is really impressive how well it works.
It looks like you have a little angle grinder because as you swirl, the barnacles just dissolve.
The process doesn't work unless you keep the acid moving.
On the shafts, I use some toilet brushes that reach right up to the upper cutless bearings.
I buy rubber gauntlets from the local fisherman's co-op and I always use eye protection goggles - the acid is nasty stuff.
By the time the pressure washer operator has finished pressure washing the rest of the hull, we have usually finished doing the props, shafts, rudders, P brackets and trim tabs.
And they end up like this:-





Of course, not all boatyards allow you to work on your boats but at Sant Carles, we have a really helpful boatyard and as long as we respect their jobs, they give us the time to do what we want.

The lift in the photos was during one of our free "lift and scrubs" that we get in Sant Carles so the boat was out of the water for about an hour or so and then relaunched.
It is a great feeling driving the boat back to her berth after a wash like that - she goes EXACTLY where I want her to go - and all nice and clean ready to go cruising.
We tend to have a lift and wash before going anywhere - saves on fuel of course as well as having a nice clean boat to swim around.

I have tried lots of different prop treatments (including Velox) - in my experience, it just comes off when you use the boat.
IMHO, nothing works as well as nicely polished metalwork which you clean before use.

 

[Portofino]

^^^^ Hurricanes area looks super aggressive.
In the CdA or Liguria you don’t need any mid season lifts for the AF on the hull .
Liguaria is better for the stern gear too in my experience.

Was wondering if all that 2 x free lift and even “ gentle “ blow off with a jet wash mid season undoes the AF put on ( I presume April / May ) ? Well I can’t see it doing it any good .
Then you end up really dependant on the mid term lifts .

The hull stays smooth ( read fuel + speed efficient) all season after being done in May / June ish ) I arrange it the week before the first summer trip .

Suppose with fuel price hikes of late any % improvements on consumption focuses the mind .

The real issue , the silent killer of marine diesels in bigger boats is overloading.
In the absence of load gauges / indicators on your dash , fouled props even a lightish accretion ramps up the “ load “ disproportionately .
I have said gauges ( MMDS) so watch it carefully.In fact set my cruise on it namely 80;% .
Not the rpm , because” I did it last time “ , and just accept what speed the 80;% load ……with that state of fouling produces .

I know with Arnesons ( Chris’s Pershing ) they are even more sensitive to overloading due to less than surgical spec prop hygiene.

So really in my view prop hygiene on bigger boats , planing boats needs looking @ from a engine conservative pov first and you just happen to get as a secondary byproduct better mpg , which @€ 2.20 + L is not inconsiderable.

 

[Bigplumbs]

I’ve bought a plastic wire brush @ £3.99

you could afford a couple at that price

 

[DAW]

I agree with Porto's comments so far as the CdA is concerned ... There is no need for a mid season lift to clean the hull as most antifoul treatments will last a full season (and often more) without any significant growth. Fouling of the props is the main problem, with a heavy impact on performance and fuel economy. The season starts here in earnest in June, so my boat is usually lifted at the end of May. By the end of July, two months later, I've typically lost about 10% from top speed and fuel efficiency so I arrange for either a short lift for acid cleaning (some shipyards will do this with the boat in the slings over a lunch break) or for a diver to scrub the props and this restores performance completely.

Over the years, I've asked a couple of different shipyards about treatments for props, etc. While they are all happy to do whatever the customer wants, the general opinion of the more reputable ones seems to be it's not a wise use of the money. They recommend a mid-season clean (whether by lift or diver) as the best approach ... the cost is similar and it delivers more predictable results.

 

[TonyR123]

Hurricane - my boat has never had anywhere near the growth on yours!

Mine is lifted once a year. I get propspeed applied and for me it does reduce growth. Costs me about €1400. Is it worth it? Who knows. But the boat is faster for longer in the season with it.

 

[jointventureII]

@Chris H we tried Propspeed on the 108 (triple arneson) a few years ago, it lasted less than a month and that was applied by Amico who did our old Sunseeker 92 the previous 4 years (and did it perfectly).

As has been mentioned it just can't deal with the force applied.

We have ASD16s and yes it's a pain to clean them but I recommend a dive air bottle on the swim platform and an extended breather tube, so you can stay underwater without needed to resurface all the time. Snorkels work but for us, the central prop is lower than the P/S and just too low in the water to properly reach from the surface.

Alternatively the divers here offer an underwater polishing service, €900 for our 3.

 

[Portofino]

Think I paid @€499. Over 10 yrs ago .Lasts 20 mins enough to do two props , costs about €4 to refill it at the dive centre .
There may be other dive solutions.
You are only less than 2 m deep just saves all the snorkelling.*

Also handy it’s intended use for prop pot fouling and bow thruster tunnel unblocking etc .

* officially seek professional instruction there thats my arse covered in todays litigation world

 

[jcwads]

View attachment 137776
Think I paid @€499. Over 10 yrs ago .Lasts 20 mins enough to do two props , costs about €4 to refill it at the dive centre .
There may be other dive solutions.
You are only less than 2 m deep just saves all the snorkelling.*

Also handy it’s intended use for prop pot fouling and bow thruster tunnel unblocking etc .

* officially seek professional instruction there thats my arse covered in todays litigation world

I’ve got a similar setup, recently purchased. Brand is Smaco. Came in use in June when I was checking the props, and diagnosed a bushed prop. Also useful for rope incidents etc.. lasts 20 mins. Only for shallow stuff.

 

[julians]

These seem decent for a small scuba dive set

Mini Dive - Diving tank refillable - Mini diving oxygen tank

 

[Chris H]

I’ve no problem cleaning the drives & props with a snorkel, it’s just the frequency.

 

[Hurricane]

I’ve no problem cleaning the drives & props with a snorkel, it’s just the frequency.

I bet you cant do it as well as if it were in the slings.

 

[Chris H]

I bet you cant do it as well as if it were in the slings.

Only because I can’t use acid, the props on my arneson‘s are only just below the water.

 

[Chris H]

 

[MapisM]

Beware, Chris:
that level of props growth is enough to reduce the speed by 10% or more in a shafts boat.
But with Arnesons, it's borderline to running engines at (if not above!) full load, even below WOT.
And that's the very last thing you want to happen to them!

 

[Portofino]

Hows the trim ram seal maintenance going ? The steering two ram seals ?

 

[Chris H]

Beware, Chris:
that level of props growth is enough to reduce the speed by 10% or more in a shafts boat.
But with Arnesons, it's borderline to running engines at (if not above!) full load, even below WOT.
And that's the very last thing you want to happen to them!

Yep, that’s why I have to clean them every two weeks in the summer, it won’t get on the plane when they have that much growth on them.