Vapor Vs Media Blasting

[Royalratch]

I spoke to a guy today about getting my engine done and he says he doesn't recommend vapor blasting. His work and credentials are exemplary.

Now I like a maverick but his logic was sound. Vapor blasting may not leave bits in your engine but the finish is so smooth that paint cannot properly adhere to it and so it doesn't create as durable a finish as media blasting.

He recommended media blasting to get a good key for the paint and to be very thorough when blowing left over stuff out.

Load of mollocks?

[uk kev]

depends what the media is?

[Mark Tiller]

are u saying that for an engine remaining bare alloy the vapour would be best? and if it will need painting soda/bead would be better?
i assume with vapour there are no bits to get stuck inside the engine

[RAYZ1]

doesnt vapour blasting use a media carried in water at hi pressure?, keep clear of bead blasting, soda gives a nice finish without the deep sheen of the vapour blast.

[Royalratch]

I think what he meant was if you're painting your engine then a super smooth surface is no good.

[RAYZ1]

I think what he meant was if you're painting your engine then a super smooth surface is no good.

I understand that, Dave Marsden uses Steve smethurst to finish all his cases before painting, Steves finish is is very smooth - smoother than VB, I think whats important is that the paint used is self etching to the alloy

[Al]

My Steve Smethurst vapour blasted top end took paint well and continues to stick well. PJ1 satin if youre asking.

The only regret i have from the first time i did it some years ago was not having the parts professionally de-greased before they are blasted. In hindsight it would have prevented several issues. Similarly, had i taken out the press fit plugs etc life would have been considerably easier. Clean out the threads and blank off with old bolts is a labour saver too.

One thing that really pissed me off though was that the head was put in the 'tumbler' not loose as the name suggests but a machine that rotates parts bolted to a frame within a cabinet with a static nozzel. They didnt blank off the wells that the buckets run in or the valve guides and these machined 'close tolerance' surfaces came back with a gritty and coarse surface finish.

AL

[Royalratch]

The valve gear issue is a good point!