Polishing Stainless Steel Screws Revisited

To the readers:

In my June 2001 column I answered a question regarding options to polish stainless steel screws. The following readers were able to elaborate beyond what I could do. Thanks for reading and responding.

• As a subscriber to PF I always make it a point to read your article. In the June 2001 issue, a question came up regarding how to polish stainless steel screws. I would like to add electropolishing as a suitable process for screws and fasteners. I am a regular reader of your column. I noted in the June 2001 issue that you did not recommend chemical polishing as a method to polish stainless steel screws. Enclosed for your review is a technical data sheet for our product, a chemical bright dip being used throughout the U.S. to chemically polish 300 series stainless steels. It can work very well in a polypropylene rotating barrel or polypropylene dipping basket, which will withstand 175F. S.O.
  
• We electropolish hundreds of thousands of stainless steel fasteners, 300 series as well as 400 series stainless steel. We can either rack electropolish individual screws or bulk electropolish screws. Rack electropolishing controls the tolerances to ±0.0001 inch off the major pitch diameter. Whereas bulk electropolishing requires a go and no-go thread gage to set up for processing to control stock removal, it does not offer the uniformity available with rack electropolishing. Please note that bulk electropolishing is not to be compared to rack electropolishing when it comes to tolerance control during the metal removal process. Bulk electropolishing is a low-cost effective means of achieving a bright, passivated finish. Each process is certifiable to ASTM A-967-99. J.S.
  
• Just got a chance to read the June issue and saw your comments on the subject of polishing stainless steel screws. Just for your own information, most fasteners that are burnished in mass finishing systems do not use any media. Part-on-part is a very effective method of working screws and other fasteners. This method does require the use of a good lubricating chemical that can also assist in brightening. A.K.

Answer:

Many suppliers can be found on pages 391-392 of the Products Finishing Directory and Technology Guide under Chemical Polishing Processes.