Epec's Blog | Electronics Manufacturing Solutions

When requesting a printed circuit board (PCB) quotation or placing an order, it is important to communicate all product requirements as clearly and completely as possible. Even seemingly minor omissions can create confusion during quoting, affect supplier assumptions, and ultimately impact cost, lead time, or manufacturability.

Two years ago I wrote about why printed circuit board (PCB) shops in North America were continuing to close. Now, in the last two weeks, we have seen two more shops (Dynamic & Proto and ITO Industries) cease their manufacturing operations.

As the former owner and operator of three domestic PCB facilities, I can sympathize with the management and the loyal employees that tried to make the company successful. However, much of the damage is self-inflicted as I previously discussed so rather than rehash past information I wanted to discuss some of the attributes that every customer should look for in their US PCB manufacturer.

IPC 4101 (Specification for Base Materials for Rigid and Multi-Layer Printed Circuit Boards) was released for publication in December, 1997. It was released as the replacement standard for MIL-S-13949. However, it contained a majority of the exact wording from the military standard. It maintained the “slash sheet” format appendix to the standard that specifies the resin and fiber system of different PCB laminates, along with testing parameters and properties. Initially there were 41 slash sheets, but as the industry opens up to “Lead Free” and “Green” processes, the slash sheets have increased to 66, the current revision.

When a project depends on quick-turn printed circuit boards, delays can affect schedules, assembly timelines, and product delivery commitments. While PCB fabricators are responsible for manufacturing performance, customers can play a significant role in preventing avoidable production holds.

In 2016 there were ten printed circuit board (PCB) factories that closed in the United States, including some highly sophisticated shops that were part of the TTM/Viasystems merger. Having been involved in the closing and transfer of part numbers for fifteen PCB facilities in the past twelve years, we have some first-hand advice as to how you can best minimize the risk as you change suppliers.

As a contract manufacturer, say you receive a new circuit board part to assemble that is 6-layers with a high micro-via count, has blind and buried vias, and a lead free HASL finish. The circuit board laminate requirement for meeting the Restriction of Hazardous Substances, or RoHS compliance, is strictly Glass Transition Temperature(Tg) 170.

Bow and twist of printed circuit boards (PCB) routinely rank among the highest levels of falsely identified non-conformance because it is perhaps the least understood. Envisioning a perfectly flat rigid circuit board as the standard is a fallacy believed by many incoming inspectors. Understanding the reasons and causes for PCB bow and twist can help resolve the issue at the board design stage.

Epec Engineered Technologies is one of the oldest printed circuit board companies in the U.S., building PCBs since 1952. Epec is one of the founding members of the Institute of Printed Circuits (IPC), created in 1957 to help advance the PCB industry. While visiting a customer I was asked, “Has the introduction of your new products like custom battery packs and energy efficient EC fans taken your focus and attention off of PCBs?” While I assured the customer that we are fully dedicated to PCB manufacturing, it occurred to me that as a company, we need to better demonstrate that dedication consistently to our customers.

History of PCB Manufacturing

When I started working in the printed circuit board manufacturing business 34 years ago, I believed it was a temporary job to pay the bills. Just until I was able to figure out what I really wanted to do. That was in 1982, working at a small PCB shop.

As printed circuit board (PCB) designs get more demanding with advances in technology involving complex footprints and added costs to components, incoming inspection of printed circuit boards must take higher priority.