Best medium to blast engine manifold parts with?

[The Fatty]

im trying to clean up the manifold + smooth the surface a bit. I read on various sites that blasting with baking soda is good for this, but it did nothing when i tried it. I didnt want to use sand as I thought that would be a bit harsh for what I want to do. Anyone know what I should be using? and what PSI? I used the soda at around 80psi...

 

[Gaz.]

I've sand blasted manifolds and calipers, fine for powdercoating. Soda blasting is more for carbs etc.

 

[The Fatty]

I was under the impression that sand wouldnt smooth out the surface?

 

[DannyR]

Just powder coat as it is

 

[Gaz.]

I was under the impression that sand wouldnt smooth out the surface?

It's smooth enough for powdercoat.