KCH Engineered Systems
Published

Interpreting QQ-N-290A

How does the QQ-N-290A specification apply to nickel plating, particularly in terms of the 0.75" ball restrictions and requirements?

Share

Q. My question is about QQ-N-290A. What exactly are the 0.75" ball restrictions or requirements as far as nickel plating is concerned? We are being held to a tight tolerance of 90 to 150 microinches on some very small parts and there are vast differences in opinion on what this rule means. The area being measured by cross section would never be touched by the ball because of the size of the part. What is your opinion on this? –S.A.

A. I thought it best to review my stained, old copy of QQ-N-290A before answering your question. My copy has a penciled note on it reminding me to order a copy of the newer B version (which I haven't done yet). Based on the rule, Class 1, Grade C, plating the required thickness would be 0.0010" thick with the tolerance you mentioned. The 0.75" ball does not come into play since it does not touch any of the surfaces.

Related Content

  • Troubleshooting Alkaline Zinc

    One of the most common problems that can arise when plating with alkaline zinc is an imbalance of brightener in the solution. In this helpful Ask the Expert article, Chad Murphy of Columbia Chemical discusses how different zinc metal concentrations and brightener concentrations can impact efficiency.

  • Successful South African Plater Beating the Odds

    Remaining focused on quality and reliability, Team Plating Works stays profitable in a volatile and challenging economy.  

  • A Chromium Plating Overview

    An overview of decorative and hard chromium electroplating processes.

Hitachi High-Tech FT200 series
High-performace passivates
Luster-On Products
FISCHERSCOPE® XAN® LIQUID ANALYZER
KCH Engineered Systems
PMTS 2025 Register Now!
Gardner Intelligence
OptiCenter All-in-One OC11
Fischer measurement technology