Karcher Sandblasting- Keel ?

[tom52]

I see that Karcher do a sandblaster attachment and sand for their pressure washers.
Has anyone tried it to get their keel back to bare metal prior to applying epoxy ?
Grateful for any views or actual experience.

 

[Vara]

I've used Karcher sand attachment for blasting paint and crud off a cast iron fly wheel it was very effective,but the sand was very expensive.If you can source a cheaper blasting medium it could be a runner.

 

[Talbot]

You get a much more effective sand blaster with a 3 hp air compressor and sand blast tool.

see http://www.compressormart.com/

 

[jerryat]

Yes, I tend to agree with Talbot. Friends of mine tried a similar set-up (though not with a Karcher) and although it did eventually get the old anti-fouling off, they quite sensibly gave the idea of getting back to clean metal with this method.

The gear just isn't powerful enough, and though I suppose you'd get there in the end, the sand usage, as others have said, would make a big hole in a beach!

As an idea, what we've done in our little boatyard a couple of times, is to organise three or more boats who each want something done (prep for epoxying, removal of a/f, cleaning back to bare on the keel or the like) then get a professional in to do the jobs in one hit. /forums/images/graemlins/smile.gif

It's much more economical that way and you get a pro job done with the massive compressors they use. MUCH quicker too! /forums/images/graemlins/smile.gif

 

[Tisme]

Our local tool hire people will hire out the compressor and blasting equipment so you can do it yourself.

It's cheaper to buy the grit elsewhere though.

 

[oldsaltoz]

G'day David,

Not a good idea to blast cast iron wet as it rusts in seconds, adding water will mean waiting till it's dry before applying any protective coating, by then it will be very rusty.

I dry blast cast iron keels with the wind at my back and apply a primer of zinc as soon as the blasting nozzle moves 2 inches.

Avagoodweekend......