Sand Blasting Attachment for Power Washer?

[slug zitski]

Hardtop , drainage channels to sand filters

I don’t know your region

on the US east coast is a mud gravel mess

obnoxious to work in these yards

 

[Grande Mastere Dreade]

Hardtop , drainage channels to sand filters

I don’t know your region

on the US east coast is a mud gravel mess

obnoxious to work in these yards

View attachment 552452

wth is that appendage hanging off the lower bow?

 

[longy]

Retracting bow thruster. Pretty common on good boats. Cost a lot more, but allow for much bigger prop (more thrust) & no drag when sailing. Less growth on thruster prop when retracted (no sunlight)

 

[Arcot]

Funny, I was thinking about this too, I think I may have posted it awhile back.
I think sand would be very aggressive, I guess it depends on what you're trying to achieve.
To simply remove the prior year's paint, I was wondering if you could use that attachment with baking soda, but I was thinking the soda may be dissolved by the water and not effectively provide any scrubbing power.
I'd also be very careful with a high power pressure washer (like a 5000psi one).... that alone can strip things you don't want to strip.

Slug is right, but it also depends on where you are and what the yard policies are. My current yard has a lot of rules, but then I see contractors dry sanding 50' powerboats with no dust collection at all. Technically to control it properly, you should have a tarp on the ground and all waste water needs to be collected and disposed of properly. Not easy.

No sand

Dust from loose spilled sand

is

toxic

to your lungs

and to anybody downwind

 

[Grrr...]

There is one kind of blasting that doesn't make a mess: crushed dry ice. But probably very expensive for a boat hull.

The sand or walnut shells from the blasting isn't really the issue - it's all the small particulate bottom paint that flows onto the ground. They put skirts around the boat to keep the dust contained (usually).

 

[DDW]

At least where I'm from, all of the detritus from the blasting would be considered hazardous waste, would need to be collected and disposed of in an approved way. With crushed dry ice, all you have left is the paint dust itself, a very small volume to dispose of. Much more if sand or walnut shells are used.

 

[nota]

recently got a older honda 11hp washer at claimed 3000psi
what is the best nozzle for old bottom paint
any different nozzle for barnacles bases or other hard foul bits

btw the gpm rates seem high for my home older water supply pipes
will these washers suck extra water or is the hose/pressure/meter flow the limit of performance/volume

local ground water is very hard lots of calcium/limestone
don't think these last long pumping that

 

[MaxSteel]

I have done a fair bit of shot blasting steel as in dry media. That is messy and getting quite difficult now and where I am, there are people complaining about noise and environmental issues when in actual fact they just want to shut the boat yard down and are looking for an excuse.
My solution for small stuff is a karcher pressure washer with an attachment and blast media - so wet blasting as per original post. For steel, it is not great, but good for fixing the small areas where an angle grinder can not reach. I also use a drill bit and drill to get rust out of very small areas or deep pitting. For anti foul paint etc. I would imagine a cheap wet blasting unit would work well as it is a lot less harsh. For removing normal paints and varnishes, I have found a small rig using standard pressure washers does not really do much. The great thing for jobs it can handle though is that you just need a pressure washer, attachment, media and water and as people just think you are pressure washing, they leave you alone.

Here is a video:

 

[slug zitski]

Don’t know your

I have done a fair bit of shot blasting steel as in dry media. That is messy and getting quite difficult now and where I am, there are people complaining about noise and environmental issues when in actual fact they just want to shut the boat yard down and are looking for an excuse.
My solution for small stuff is a karcher pressure washer with an attachment and blast media - so wet blasting as per original post. For steel, it is not great, but good for fixing the small areas where an angle grinder can not reach. I also use a drill bit and drill to get rust out of very small areas or deep pitting. For anti foul paint etc. I would imagine a cheap wet blasting unit would work well as it is a lot less harsh. For removing normal paints and varnishes, I have found a small rig using standard pressure washers does not really do much. The great thing for jobs it can handle though is that you just need a pressure washer, attachment, media and water and as people just think you are pressure washing, they leave you alone.

Here is a video:

don’t know your project …on a metal boat we cut a hole , perhaps two holes in the bottom ..from the outside …then blast the tank while standing outside , with the tank top on . Then it’s painted …the top comes off, plate welded up and painted

very little work is done with the tank opened

 

[MaxSteel]

Don’t know your

don’t know your project …on a metal boat we cut a hole , perhaps two holes in the bottom ..from the outside …then blast the tank while standing outside , with the tank top on . Then it’s painted …the top comes off, plate welded up and painted

very little work is done with the tank opened

Yes, I did shot blasting inside my outriggers by cutting an access hole, but I had to get inside to do them as they are 9 metres long and 1 metre diameter. It was not as bad as it sounds as I had a big 12” fan with a long exhaust tube. It can shift 65m3 of air a minute and kept the visibility at a reasonable level. the fan is about $200 and I use it a lot now when I am painting epoxy (brush or roller) and such. It is so effective even in such confined spaces that I do need to wear a breathing mask (Obviously when shot blasting, I use a force fed mask from a fully filtered exterior air supply).