Wet Blasting, Aquablasting, Vapour blasting ....

[Charlie]

Hi Guys,

Anyone have any experiences with wet blasting? Got a couple of 432's to do and it looks a lot less messier than conventional grit blasting! Plus don't need air fed helmets etc... Any thoughts appreciated before I spend.

Cheers, C.

[Scammell4199]

Don't use wet blasting on ferrous materials, the rust will set in before you've even finished, so you'll be wasting you time and money.

Stick to a big old pressure pot, lots of air and a load of JBlast grit.

 

Good luck, Richard

[ruxy]

Priming / topcoat paints have been developed to lock + holdout better on flash rust rather than to such as SIS SA2.5 (white metal) , there are at times advantages using wet-blast. Obviously you need to follow a full system start to finish inc. times between operations.

[paulbrook]

There is not really less mess - I have experience of both approaches and whilst there may be some slight differences in application, it is the abrasive that does the work and at the end of the day there will be a ton or two of it to clear up. Now there may be less dust with the wet system but we have found that using decent grit keeps the dust down anyway.

 

The air fed mask is no great hardship, you will have to wear PPE anyway.

 

One trick which we now do regularly (because it saves so much time and money) is to "kill" the existing paint first with a decent blowlamp/propane fan. No need to set fire to the whole lot, you just go over everything and scorch the paint. It has the effect of making the paint much more brittle and it peels off with the blaster so much quicker (and cleaner).

 

As for treatment if you wet blast I did a Mack chassis 6 years ago with wet blasting - and it started to go yellowy with rust almost instantaneously. I used a garden spray full of stuff called Fertan which blackened everything. I then pressure washed it all off again (counter intuitive I know but there you go) and sprayed the lot with primer. That chassis is still in primer and is as rust free today as it was then - have a look here http://s484.photobucket.com/user/RustyTrucks/library/Mack%20May%202009

[utt61]

I bought a wet blasting unit to use during the restoration of a large steam crane.

 

In my experience wet blasting is superior in just about every respect. It is more controllable, there is less airborne mess, and it actually seems to clean better. There is no problem with surface rust, and the best overall results we've had have been to wet blast, acid wash the surface when dry (dilute phosphoric acid, sold for this purpose), then scotchbrite, then prime, undercoat and paint. This has produced levels of adhesion many times better than traditional restoration methods with little extra hassle.

 

For optimal paint adhesion a "flash rust" surface is a good thing.

 

I would however never operate the wet blaster without an air-fed helmet.

[andym]

Whatever method you choose, for a couple of vehicles it would probably be easier/cheaper to pay someone who does it for a living?

 

Andy