mig-slag removal... from the Cu coating and such

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Howdy!   I think I am getting very tiny inclusions of slag when multi-passing with my tiny 120 volt mig welder.  The slag is whats leftovers from copper coating I think. Maybee not.  I think I'm using .030 er70S  from memory. Gas  is C-25. It is Lincoln brand wire. A common off the shelf reel from a farm store. So, I wire wheel the hell out of my weld, before each additional pass.  Am I missing some kinda of trick that I should know about?  It's not like smaw slag, it's different.  Like bright shiny metallic glass, and allthough on top, seems to somewhat.. fuse with the base, but maybee it solidifies at a different time from the metal pool, and one forms around the other.  Anyway!  any tricks?  have more patience?  a different wheel?  Thanks!  Brian Lee  Sparkeee24Last edited by Sparkeee24; 08-26-2005 at 01:03 AM.Reason: forgot specific info
Reply:It is a good idea to remove the glass between passes.  Bear in mind I don't unless I am doing a weld test.  I then take a wire brush and give it a once over.  In most cases the second weld will burn right through the glass but on a test one doesn't gamble.  The welding wire has extra silicon in the alloy.  When it mixes in the weld pool it binds with any oxygen and forms the silicon oxide ( glass ) on the surface.  The welding wire is doing its job.
Reply:Sparkeee24, you dont have to get all the slag off by wire wheeling every time. Most times on a multi-pass you can just scratch it with a file or screwjabber and get the most off and be ok.
Reply:Howdy!  Maybee I'm being too picky?  My welds strength are not in question for the purposes I use them for.  I am looking (as always) towards perfection. as unattainable as it is :P  My welds are not production, or anything more then structural with a moderate consideration for form.  as of yet.  Thanks for the advice folks   I will try the sharp edge of a file, and scraping with my beeter screwdriver ground to a point next.  Take care folks!  Brian Lee  Sparkeee24