Vapor Blasting

[85RZwade]

I found this information helpful:

https://pittsburghsprayequip.com/blogs/pittsburgh-spray-equipment-company/how-to-soda-blast-in-a-regular-sandblaster-a-complete-guide

[quocle603]

I've built my own vapor blaster and designed nozzles for the guns used. My top end looks great after doing a new rounds of blasting.

[irk_miller]

I typically vapor hone aluminum parts with a mixed blend of glass bead 170 - 325 mesh.  For parts I intend to clear coat, I add 140 mesh aluminum oxide to the mix.  Glass bead vapor honing isn't good for painted parts, as it polishes the surfaces and lacks the bite needed to bind durable paint coatings to the aluminum. That's not to say it won't work, but that you run a much higher risk of your paint peeling or chipping months or years later.  Dry or wet blasting doesn't make much of a difference as far as paint is concerned, since the water is really just a vehicle for the blasting medium and serves to knock down dust and clean as it blasts.  You absolutely can vapor hone machined surfaces, but do not do it with anything but glass bead as your blasting medium.  Aluminum oxide and silicon carbide will remove material and have an effect on tolerances.  On high tolerance parts, or parts where movement and oil is necessary, I highly recommend hitting all parts with compressed air in every hole, cavity, thread, etc.  Follow it up with a rinse, then blow it with compressed air again.  If there is glass bead left in a threaded hole, there is a huge risk of that glass bead become a thread lock like you've never experienced before.  If you get glass bead in a bearing or rotating part, you might as well consider them together for life.  The bead gets into places you never though possible.  When I vapor hone heads, I always follow up with a valve grind/polish.  I don't for journals, and so far I've never had an issue. 

[85RZwade]

  thanks for the excellent information