To reach the best EP results, we advice to a User to implement some practical guide lines:
• Choose right materials. Titanium, Nitinol, high Ni-Cr St Steels which are C-Si-S free – these metals have a good chance of lustrous EP, while the presence of metalloids in the metal, or using of not alloyed steels, need special consideration of the electro-polisher, and results are not for grant.
• The history of the metal treatment is of crucial importance for the EP results. If you want them best, consult your electro-polisher for choosing pre- and post machining treatment, including stages made by supplier of the metal, and take his considerations in account.
• Take in account quality tolerances of metals. Sometimes, metal quality deviations, or hidden surface defects, may be resulted in bad electro-polish.
• Geometry and dimensions of the part have considerable influence on the EP results. Parts of the same material behave differently when having different geometry and dimensions. Spare time for tests.
• Analyze and define as exactly as possible your requirements to parts after EP; use references and control samples and consult your electro-polisher;
• Remember that for any EP effect you “pay” by dimensions of the treated part. Thumb rules: to reach uniform brightness, EP has to remove few microns from the machining part of high finishing, and up to 30 microns from the machining part of low finishing; to dissolve light burrs, EP has to remove 10 microns, and for heavy burrs up to 50 microns must be removed; to discolor light oxide spots, EP has to remove 5 microns, up to 30 microns for heavy oxidation; to smooth scratches, EP to has to remove five times more thickness than the deepness of the scratches; every 10 microns of removed thickness add 1 micron to tolerance.
• A skilled electro-polisher will supply you with the best solutions, including complicated cases, just consult him and ask him for tests at the earliest stage you can.