cob blasting with sandblaster??

[northernss454]

HI i have a question about cob blasting. I have access to a industrial sandblaster and compressor. But i want to cob blast my log house,i ts really grey from the weather. Now can I use cob media in a normal sandblaster or do I have to change tips or something. I searched high and low and could not find answer on Internet. I am hoping someone has some experience with this and could help me out.
Thanks

[beenthere]

Asking cab or cob?

I assume corn cob as the blasting material.

There are several google hits that discuss the pro's and con's. Also some videos to see the effects as the blasting is done. One log home company is a bit negative about this treatment.  http://www.fixlogs.com/corncobdanger.html

If your logs are grey, it is likely mildew. I'd suggest trying bleach first, and see how that does.

And some hits for corncob nozzles. 

[Tom]

And just for some miscellaneous information.  The silver color and fuzzy texture that accumulates on pine and some other weathered woods is a natural preservative.  Cleaning it off opens the wood up to the elements again.  I forget where I read this.  It was a long time ago.