Parkerdizing Bolts and Nuts

Hi

I want to start with the parkerizing of the nuts and bolts and some of the parts within the next week or two.  I have been studying the parkerizing process and this is what it is about:

WHAT IS PARKERIZING?

Parkerizing or Phosphating is a Metal Finish that really gained in popularity during WW2 when the US Government was looking to replace the typical blued finish on most small arms with a Rust Resistant and Anti Reflective Finish that would be both Durable and Abrasion Resistant and hold up in all weather extremes.

An Example of the Parkering Process (http://huntersrungunshop.com)

 

The Parkerizing technique is a Phosphate etching process that produces a hard matte or dull finish that is both very durable and anti reflective and with excellent oil holding properties.  The process involves submerging the metal part into a phosphoric acid solution whose key ingredient is often zinc or manganese, with varying additional amounts of nitrates, chlorates, and copper.

THE PARKERIZING PROCESS

The Parkerizing process is as follows:

• It starts with the sand-blasting of the steel parts to remove all the rust, paint and oil.
• Once the steel parts have been cleaned, the Parkerizing Solution is mixed into water in a stainless steel container.
• The water in this container is then heated to around  90–99 °C (190–210 °F).
• When the water has reached the required temperature, the clean steel parts are placed in the water for a period ranging between 5 and 15 minutes.  A stream of small bubbles will be emitted from the metal parts as the parkerizing process takes place - when the bubbling stops, the process is complete.  However, metal should not be left in the water for long periods of time, as the acid will dissolve the metal.
• The steel parts must then be neutralised to remove all of the acid.  This is normally done by rinsing the parts in water.
• The steel parts are then oiled to protect against corrosion.

More about this at a later stage.