media blasting
 

Is it ok to media blast the iron(s) surfaces with 80 grit glass bead? I can't get the coolant seal grooves cleaned out and this seems to be the best idea.

Dental tools and "super clean" by castrol lay iron flat and allow the super clean to soak in to the crap and use dental tools and old side seals to get it out. Is it rusty? If so use CLR and let that soak but bead blasting I think will have a profound affect on the sharpness of the water jacket grooves

crushed walnut shells for engine internals.

I used muratic acid and started a fire, it reacted with the red mechanic rag, smoked and then caught fire. Other than that, it worked fairly well, but there is still a many spots where the rusty krusty coolant seal crap is stuck. I've used dental picks and that did ok, but takes forever and a day. I do have a couple of a irons that have had the coolant groove break away that have served as porting practice, so I guess any media blasting will be preformed on them first, just to make sure. Thanks for the help.

IF I were to media Blast. I would use a 80 Grit Glass Bead, I would also mask of the wear surfaces of the iron with a couple layers of heavy duty Duct Tape (or better yet: Resist Masking, used by signmakers)