Keeping Printed Circuit Boards Clean with Custom Wire Baskets

August 10, 2016 | Custom Wire Baskets, Wire Forms

Lidded Baskets such as this one are great for ultrasonic parts cleaning.Electronics manufacturing is delicate work. The printed circuit boards (PCBs) made by manufacturers are quite delicate, and need to be protected from scratches and surface contaminants to maintain the high quality sought by consumers.

Damaged, dirty boards are more susceptible to fatal faults, and reduce the overall stability of the final product, whether it’s a phone, computer, or robot.

Keeping delicate circuit boards safe through the entirety of the manufacturing process is a difficult task. Each board must be kept safely isolated and no liquids can be allowed to collect on their surface—even though the boards will be submerged for an ultrasonic cleaning cycle.

On a recent order, Marlin Steel’s engineers were tasked with creating the perfect PCB panel cleaning basket for a client’s ultrasonic cleaning process.

For this custom design, the customer had identified several different design elements from a number of existing basket designs that they felt would best compliment their needs. This new basket would borrow:

  • The lid from Basket #1212001
  • Dividers from Baskets #745001 and #929992
  • Mesh spacing from Basket #1194001
  • Suspension-compatible handles from Basket #898001

Naturally, the disparate pieces of five separate custom wire basket designs couldn’t just be cobbled together like the limbs of Frankenstein’s monster. There would be additional work in adjusting the design of each piece to create a cohesive whole.

Creating a Cohesive Design That Met the Demands of the Ultrasonic Cleaning Process

On this custom wire basket order, the client had several requests for specific design elements to meet the challenges of their parts cleaning process. However, before designing the basket, Marlin’s engineers reviewed the questionnaire filled out by the client. This document laid out the specifics of the process, including:

  • The size of the parts to be washed: PCBs as small as 1/8” in diameter or as large as 4” x 5”
  • Dimensions of the ultrasonic parts cleaning tank: 12” x 28” x 32.5”, with a desired suspension depth of 16.25”
  • Maximum load weight: 5 pounds
  • Chemical solution used in the cleaning process: water and a weak acidic detergent
  • Temperature of wash process: 100°F to 115°F
  • Duration of wash cycle: 30 minutes at most

The needs of this basket’s design would create some conflicts.

The ultra-narrow spacing of the wires on this basket were critical for holding the tiny PCBs being manufactured by Marlin's client.For example, in an ultrasonic parts washing basket, you typically want as much open space as possible between the wires so they don’t interfere with the ultrasonic waves emitted by the transducer. However, the spacing needed to be tight to hold tiny 1/8”-diameter parts securely.

To compensate for the narrow distance between the wires, especially fine wires had to be used to minimize interference with the ultrasonic cleaning cycle. While such fine wires would be more susceptible to bending under heavy weight, the basket’s predefined 5 lb. maximum load was light enough for thinner wires to take.

Each element of the basket design the client wanted was carefully considered and adjusted to fit the dimensions of both the parts to be washed and the tank the basket will be suspended in. This would mean a total change of wire counts and lengths, as well as other alterations to accommodate the ability to swap different dividers into and out of the basket for different parts loads.

Finalizing the Design

After working in the different design features the client needed, Marlin’s engineering team started running virtual tests of the basket’s design to identify key fault points.

By using a computerized simulation, each iteration of the basket’s design could be checked against hundreds or thousands of uses in mere minutes. Real-world testing would have taken weeks or even months to accomplish this.

If any flaw was found that would cause the basket to fail, the cause of the fault would be pointed out in an automated report. Armed with this information, the design team would re-work the basket design to eliminate that fault.

This testing was repeated over and over until the basket design was finally able to pass the rigorous virtual test.

The end result was a sturdy, reliable custom ultrasonic parts washing basket that could hold miniscule printed circuit boards and keep them safe from the stresses of the finishing process to minimize parts rejection and scrap rates.

Learn more about how Marlin Steel can make the perfect parts manufacturing and cleaning baskets for your own needs today, whether you’re making small delicate electronics, or massive, sturdy engine components.

Download our case study!