If its the slick smooth finish your looking for with the soda blasting then use Plastic.
I visited a local body shop that does some soda blasting and he was sure to tell me that soda will only take paint off......will not touch any kind of rust.
That being sad I have had some experience with the PLASTIC blasting but it is not cheap. Going rate here at the only place I know that does it is $85 and hour plus the plastic. I can tell you first hand experience that it will not take ANY rust off, only paint.
But, if it will do a slick job and you will not have to worry about it leaching out like the soda.
I actually have a 5 gal bucket of the plastic in my shop. I plan to use it in my blasting cabinet but the problem is everything I have has rust on it!!
Just my thoughts. I hope this helps in some way/ideas.

Edit: the plastic looks like ground up tailight lens and bumpers!!!

Last edited by Achipmunk; 03/20/2010 3:33 AM.

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