bead blast or not

[stroker]

i am restoring a 47 knucklehead and want to know the best way to prep my motor and tranny cases bead blast vapor hone or hand clean with simple green or something thanks in advance i'm trying for stock high point type of finish and don't want to mess them up

[T. Cotten]

Please explain "stock high point type of finish". Stroker...

And "vapor hone", too.

I'm not too old to learn new ways!

....Cotten

[stroker]

vapor hone is wet bead blasting leaves a shinny finish high point is what are amca judes looking for or accepting

[larry]

I try to avoid sand or glass bead on engine parts as the media gets trapped in the metal to be released later. Baking soda blasting dissolves in water. In many cases, scrubbing by hand proves sufficient.

[stroker]

thanks larry i dont need sand or glass coming loose later on

[T. Cotten]

thanks larry i dont need sand or glass coming loose later on

Sand sticks because its sharp, Stroker!

That, and things like 'black beauty' and even ALOX embed, but sometimes something aggressive is still a necessary first step. Then more steps to prep that properly,.. and finally encapsulating internal surfaces. Sometimes dressing external welds and boogers, you may want to focus some steel shot, before beading it all at high enough pressure that it 'bounces', and finally ADALOX soft brushing.

So maybe judges think this 'vapor blast' is closest to "as it left the factory"?

....Cotten

[stroker]

thanks cotten

[T. Cotten]

thanks cotten

Ain't you gonna ask about 'encapsulating', Stroker?

Its more important than even pleasing the judges.

....Cotten
PS: Vapor blasting certainly sounds like it would cut down on the dust. I burnt up another collector last week.

[stroker]

yes what is encapsulating

[T. Cotten]

yes what is encapsulating

Basically, Stroker,..

Its just painting the internal surfaces not only to lock down any residual abrasives, but to seal any porosities, and let the oil settle to the sump better.

The traditional coating was 'Gasoila', but there has got to be an improved formula today. Baked 'Glyptal' became the standard for decades, but it also suffered from any leakage past a petcock that might enter the motor while sitting. OHV's are most prone to this issue.
Unfortunately, although there may be many fine coatings, constantly changing modern fuels do not treat them all the same.

Back to the externals, are there any repairs or blemishes to dress before a final finish? Judges like to point their fingers at things like that, if they can't find anything else.

.....Cotten

[Rodger Brandstatter]

The last couple of projects that I did that involved complete engine disassembly I blasted the aluminum engine cases with 80 grit glass beads at about 60 p.s.i. and as a final clean-up put them in an heated ultrasonic cleaner. A guy I know has one large enough for cases. It gives you a little extra piece of mind that nothing should be coming out of the pores in the aluminum.

[stroker]

the cases are very strait no repairs. inside was coated with some red looking sealer with half worn off or missing i am going to remove the remainder and try no sealer unless there is some bullet proof good stuff any opinions going with no coatings? also is it safe to boil the cases to remove any residual blasting media thanks in advance for opinions and advice

[exeric]

I stopped bead blasting motor, and transmission cases in favor of hand washing, and scrubbing. I use a variety of cleaners, brushes, Scotch-brite, and chemicals to make the aluminum castings clean but I strive not to change the texture of the castings. I like the look of cleaned aluminum, and think it's much closer in appearance to an original casting.

[larry]

sodam74.JPG An example of soda blasting. Looks like conventional blasting, but no grit. Washing in water dissolves residue.

[T. Cotten]

Looks like it has a decent mil-profile to hold paint, Larry!

Beads don't, but I haven't a place for a fifth blast cabinet, and can't pass on the cost to the customer. I would still be brushing the internals anyway.

And you really want a sealer, Stroker, for the three reasons I gave.
The factorys thought so too, and that's why they used the 'red stuff' that no longer resists fuels. Either we search for a modern fuel-proof sealer, or bake-on Glyptal and make certain the petcock is absolute.

For the external appearance, we must first decide whose eye we must please.
An individual can take great pride, and a whole lot of time and effort, to produce a decent finish, but a pro shop would have to charge hundred$, so that's why we blast, prep, and seal, when necessary.

....Cotten