Pressure Wash Underwater ?

[alec]

Would it work ?

The thought came to me this weekend while scrubbing from the pontoon.

Anyone tried it ?

 

[nimbusgb]

Yes it will. Not as effective, you need to be closer in to get good cleaning.

If you were to try it as a swimmer I suspect you would move away from the boat unless you were anchored somehow!

 

[AIDY]

yes i tried it last year but its not that effective ....make sure the end is under the water as the water squirts back at you /forums/images/graemlins/laugh.gif

 

[ShipsWoofy]

Mine kept blowing the cct breakers.

 

[decdeb]

yeah it works. Flippers are a good idea to stop you from moving backwards.....

 

[William_H]

I helped a friend antifoul his Mobo last week. The paint had lasted one year and extremely well compared to similar paint on sail boats. Obviously his occasional 30 knot trips help a lot to clean off the weed.

I don't imagine a pressure washer could do much more than 30 knots under water.

I find the best thing for my sail boat is to get into the water and scrub with a rag or scotch bright or even a scraper. But then we get savage weed growth here. olewill

 

[steve_l]

You're not supposed to put the whole machine under water /forums/images/graemlins/smile.gif /forums/images/graemlins/smile.gif /forums/images/graemlins/smile.gif

 

[Mark-1]

I'm thinking of trying this this weekend. Any further thoughts since this discussion in 2008?

 

[PCUK]

I've often thought of a fixed unit on the sea bottom that the boat motors through, It would have to have immense pressure but could revolutionise bottom scrubbing.

 

[sarabande]

I recall a commercial video (probably not on Youtube) about a compressed air and water system being effective. The release of pressure in the air bubbles (similar to cavitation) just blasted the weeds and barnicles off, with t he water jet carrying the debris away.

It might be worth trying to lift up momentarily the intake pipe of the pressure washer above the supply tank surface to entrain and compress air.

Or otherwise induce air into the supply line.

 

[PCUK]

How about fixing the air line from one of those £99 compressors to the pressure washer jet to give the combined air and water?

 

[JerryHawkins]

Just be careful if introducing a lot of bubbles under your boat... https://www.newscientist.com/article/dn1350-bubbling-seas-can-sink-ships/

 

[sarabande]

Good find, Jerry.


Just thinking about the cavitation suggestion... perhaps something to do with it, but also likely that the water jet can 'pulse' at a greater pressure into an air bubble. A sort of shock treatment.

 

[John the kiwi]

Just be careful if introducing a lot of bubbles under your boat... https://www.newscientist.com/article/dn1350-bubbling-seas-can-sink-ships/

Stop press: Scientists discover something already well known! Well known among surfers anyway. You can't float in the highly aerated water of a breaking wave. I have a vivid memory of being rolled along the sea floor in aerated water and totally powerless to do anything about it.

 

[dgadee]

We need robots tied to the boat with an umbilical cord which will work away at the fouling in our absence. Patent pending.

 

[JumbleDuck]

I'm thinking of trying this this weekend. Any further thoughts since this discussion in 2008?

When my last boat was in Kirkcudbriight marina I used to remove the fringe of greenery which grew round her waterline (the only thing that did, thanks to constantly changing salinity) with my pressure washer. It worked fine, but with an effective range of an inch or so - the nozzle had to be practically against the target.

 

[Kelpie]

We need robots tied to the boat with an umbilical cord which will work away at the fouling in our absence. Patent pending.

The technology already exists, although they aren't self driving (yet). I operate one of these as my day job.
270 bar pressure fed through an umbilical to a neutrally buoyant tracked robot that you drive around blasting off fouling. Designed for fish farm nets but I guess it might work on a boat too... have always fancied trying it...

http://www.mpi-norway.com/products/ronc

 

[Heckler]

Stop press: Scientists discover something already well known! Well known among surfers anyway. You can't float in the highly aerated water of a breaking wave. I have a vivid memory of being rolled along the sea floor in aerated water and totally powerless to do anything about it.

Years ago off Gabon, a blowout in an offshore well, the nosy supply boat nearly sank!

 

[LittleSister]

Nearly 50 years ago I worked briefly in a Cornish China clay mine. My job was to sit in a little cabin and, using a set of control levers, direct a jet of water that blasted rocks and soil out of the wall of the deep, open cast mine. If I remember correctly, the jet was 7" in diameter, and the water exited it at 120mph. (I was warned it could cut a man in half.)

A few of those underwater in V formation = drive-thru bottom scrub! (Don't forget to withdraw your log impeller! )

 

[Yngmar]

Drive-in boatwash exists: http://driveinboatwash.com/en/for-boat-owners/