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Will oil on black oxided screws affect functionality of PCB?

I am a quality engineer that works here in Thailand in a PCB manufacturing plant. My question is if the small quantity of oil that is put onto the black oxide finished screw for corrosion purposes will affect functionality of PCB?

Is there any other way that you can prevent rust for black oxide finishes without using oil?

Jonathan Ponferrada
quality engineer - Pathumthani, Thailand
January 29, 2008

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First of two simultaneous responses -- January 31, 2008

I assume that you mean a printed wiring board. PCB was changed to PWB because of the bad connotation of PCB in the environment and health issues.
My guess is that it would be NO, if it was a dry to the touch oil, which is one of several allowable oils. Motor oil is not acceptable for your use.
Other than oil, wax is allowed and is great, but it is expensive and not normally used, so few plating shops have it.

James Watts
- Navarre, Florida

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Second of two simultaneous responses -- January 31, 2008

Jonathan,
In normal cases the board is covered with solder mask, all soldering is complete, and the location of the hold down screws do not interfere with the function of the board.
To answer your second question, there are better materials to use other than oil. First the screws can be plated in electroless nickel containing PTFE. Teflon and silicone coatings are also other alternatives.

Mark Baker
Process Engineer - Syracuse, New York

adv.