Anyone can share experiences with a wet blasting kit for a Kärcher K2?

[Franziska]

Hi,

I want to renovate our center board case. It's about 0.8m deep, 2m long and about 0.08m wide.
The board is pivoting and the case is of marine plywood.
So the area it not huge, but quite hard to access.

Once the old paint is removed I can get enough into it to apply a layer of epoxy and fiberglass.

Here is the tricky part, we can not get the paint off with traditional tools. Space is really limited. So no sanders or scrapes & heat guns
So the first idea was a modified sand blasting hand gun. As we do not have the proper compressor and equipment we found these wet blasting kits for Kärcher and other high pressure washers available on the net.

We have a K2 Kärcher unit and I would like to know if someone has successfully used one of these wet blasting kits available on the web with one of those small K2 units.
I am a bit hesitant as it's a small unit.
Still, if it's working it would be a great way to get rid of the old paint. Few days drying thereafter and the job would be done...

I'd appreciate to hear if the K2 (or similar sized pressure washers) worked for anyone of you on a small project such as this.

Thanks, Fran

[Franziska]

Anyone have experience with this on a smallish pressure washer?

[Tillsbury]

I have experience using them on more powerful models, and they are underwhelming. You must use the correct sand. I doubt the K2 would be powerful enough to remove more than butter from toast.

[Franziska]

Thanks Tillsbury, hmmm. Might need to find a stronger washer than..

Anyone else here used this kind of setup?

[Niall leslie]

Dear Franziska,
I was briefly in the wet blasting business, dealing with osmosis. We used a Karsher wet blaster which was powered by a 12 HP Honda and operated at about 3,000 - 3,500 PSI very successfully using sand but I'm not sure how well it would work in the small space that you'd be dealing with. For hulls it worked very will with no dust but lots of mess otherwise.
Cheers,
Niall.

[roland stockham]

I second Niall in that wet blasting is effective th the right kit. I once hired a good siized gas powered rig to clean old paint and rust from a cast irn keel and it was perfect. My suggestion would be to talk to a specialist hire shop and rent the right machine rather than adapt a small one. Probably as cheap as buying the kit for the one you have. The problem with small units is that even though they develope reasonable pressure the volume is two low for grit blasting.

[Avionics_Joe]

Have you thought about using paint remover?

[Franziska]

Thanks for the info everyone.

Reg. paint remover, it does not remove two component stuff like epoxy. I need bare wood as a result, because I want to laminate over it with epoxy.

So I guess I need to hire a bigger washer....

[Avionics_Joe]

Originally Posted by Franziska

Thanks for the info everyone.

Reg. paint remover, it does not remove two component stuff like epoxy. I need bare wood as a result, because I want to laminate over it with epoxy.

So I guess I need to hire a bigger washer....

Jasco® Premium Paint & Epoxy Remover is an extremely strong stripper that effectively removes paint, varnish, lacquer, shellac, epoxy, urethane, latex or any synthetic coating. It can be used on wood, metal, concrete and masonry. The semi-paste formula works in 15 minutes or less and clings to vertical surfaces.
Premium Paint & Epoxy Remover - Jasco
Jasco › product › premium-paint-epoxy-remover

[Franziska]

Wow. That is the first paint remover I ever heared of, that claims to remove epoxy.
Hope the claim holds true for properly cured epoxy and not just for under cured or uncured epoxy.
I'll write them an email. Sounds to good to be true, but definitely worth checking.

Thanks.

[Avionics_Joe]

Your welcome, I hope it works for you and you can get it in Germany.
I have used this on 2 part epoxy paint on aircraft with very good results, in Florida, it is available in most hardware stores.

Joe

[Franziska]

That's really good news.

I have already sent them an email for info as to where I can get it over here.

[RexSnr]

I have used the kits you describe on a small boat trailer to remove rust. I used a Karcher 520M - 120bar and 450l/h. I used garnet as I had some left over from a big job. It worked reasonably well for a short time but got progressively more temperamental. In short, I worked out the ceramic??? nozzle had worn rapidly and was decreasing the venturi effect which made it extremely hard to pull sand up and into the water flow. It worked for about two hours all up but I would describe the last hour as painfully frustrating.

Being an engineer, I tried to see if I could make new nozzles but the head is cast around the nozzle so there is little chance of repairing it. in short, a very typical piece of Chinese rubbish. The rest of the unit is as new and quite well made, so it wastefull to have to chuck it out. My beef with Chinese products - rapidly consuming the worlds resources but for only an hour or so's work.

However, it was useful enough for the first hour so I actually ordered another two units as they are cheap and keep them in the workshop for small jobs. Last thing, don't believe the videos on the ad. They are clearly using a HUGE unit in comparison. Summary - small jobs only and don't expect long life.

[Franziska]

@RexSnr

Thank you for your very thorough reply too.

If I can not get the special epoxy paint stripper described above I might buy one of the units and use them for the center part of the box which is hardest to access.

Maybe I ought to find a unit which has a metal head with replacable metal nozzle of some sort.

[thinwater]

Originally Posted by Franziska

Thanks for the info everyone.

Reg. paint remover, it does not remove two component stuff like epoxy. I need bare wood as a result, because I want to laminate over it with epoxy.

So I guess I need to hire a bigger washer....

Epoxy is harder than wood. If you remove the epoxy by blasting there won't be any wood left! Seriously, power washing is a leading cause of death of wood decks, and they are just removing mildew. Cranked up to cut epoxy you will get holes right through.