5 Replies Latest reply on Sep 18, 2017 3:55 PM by james_jenkins

    Metal Polish for Ion Source


      It was a few years ago, but I did a trouble shooting and maintenance course with Agilent where we used Metal Polish (Autosol) as apposed to the Aluminium Oxide.

      I've since done this for 10 years, joining a new company a colleague has questioned it, so thought I could raise the debate here.

        • Re: Metal Polish for Ion Source

          Agilent only recommends using aluminum oxide as it is the simplest, cheapest, most versatile, and safest product to use.  Just about every other product has a residue that must be removed, including most available metal polishes.


          I have personally cleaned GCMS Ion Sources with many different products and many different processes in 34 years of working on them!  Pretty much all of them will work.  Remember, what you are doing is removing an adhered organic layer, a film, that over time covers every surface inside the GCMS vacuum manifold.  Being thorough and cleaning every face, edge, corner, hole, nook and cranny, and removing all the residue from the cleaning process may be more important than the product or process being used.   Except for the electron burn near the filaments, this typically does not take a lot of time or pressure.  The black stuff you see on the swabs and lint-free cloths is metal, not 'dirt.'  The film is removed long before that.


          The easiest is still aluminum oxide.


          Follow the cleaning procedure posted here: How to clean an Agilent GCMS Ion Source   and you will be successful.

          • Re: Metal Polish for Ion Source

            Like Paul, I have used many techniques of cleaning ion sources including Autosol.


            The Autosol is nice to work with and makes very little mess but I found I had to scrub harder to remove the ion burn marks that normally come off fairly quickly with the aluminum oxide and water slurry Agilent currently recommends.


            Another comment about Autosol, is that it contains surfactants which would normally dissolve well in water but the majority of the product is made up of hydrocarbons which is best removed with a non-polar organic solvent like hexane. So to make sure I removed all traces, I first sonicated in hexane, then wend down to acetone and then water but to get a nice clean finish on the source I had to go back up through the solvents, methanol, then acetone and finally hexane again to ensure the source was dry and didn't have any residues left on it. So my take on it was that although it is a little messier, aluminum oxide powder gives a good residue free clean and starting with water (rinsing under a tap to ensure the powder is all washed off) you can work your way from polar to non-polar solvents.


            Finishing in hexane is really nice as it dries without chilling the cleaned parts like other solvents (eg acetone and dichloromethane). When you finish in other solvents (eg acetone) water from the atmosphere condenses on the chilled surface and then eventually dries leaving water marks on the surface. Hexane doesn't seem to do this.

            • Re: Metal Polish for Ion Source

              I went ahead and flagged the “Correct Answer” on this post.  If you still need help though, please let us know and we would be happy to continue working with you.