Problem with metalizing

hello,

I am having problem with my metalizing .i can pump down to 3 x 10 -4 but my shots are coming black .it is not back streaming. i have a polycold hookup. the black layer is on top of silver layer and it is like Black ash or you can say Black Dust..it has been three days and i am running out of ideas..

Please help.
Thanks!

I didn't find the right solution from the Internet.

References:
www.svc.org/forums/messages.cfm?threadid...6E5-5C007783A3E9C58B


industrial product animation