TracerVISION
Reshoring High Speed Cable Connector Board Production
After tolerating slow production turnarounds and SMT placement issues with an offshore PCB Assembly shop, CCX Corporation turned to Tracer for a solution.
Company overview
CCX Corporation is a best in class, North American manufacturer of custom and high-speed cables and connectivity solutions. They produce custom cables according to customer specifications as well as high speed fiber, copper and power cables and a complete suite of optics. CCX employs over 200 people in Colorado and New Mexico.
Problem
CCX’s PCB Assembly supplier based in Mexico was struggling with correctly soldering a small DFN (dual-flat no-leads, SMT) component on a newly introduced product. The PCBs, arranged in 10-up arrays, were small (about 15mm square) and also quite thin. Despite some stability fixturing that the original Assembly shop had developed, Tracer Engineering came to the conclusion that the fixturing was inadequate, and was resulting in a “trampoline” effect. Basically, the fixturing didn’t support the thin boards well enough, so that when 1 DFN was placed by a pick & place machine, the vibration of that placement would disturb or skew surrounding DFNs, causing opens, shorts, and other defects. Due to the ineffectiveness of the SMT assembly process of the shop in Mexico, excessive SMT rework was required, slowing the shop’s turnaround time. This unnecessarily long turnaround time was especially painful for CCX considering that CCX was consigning parts. The shop in Mexico was tying up CCX’s cash in inventory. Like any business decision, low cost was a major factor in sourcing an assembly shop as well as an imperative restraint in moving assembly to another, perhaps more sophisticated shop. Worse yet was that CCX had already sunk cost in the special fixturing with the supplier in Mexico. The switching costs to re-establish production with a new supplier were a chief barrier to solving the problem within CCX’s budget. However, executives of the project knew something had to be done to improve the situation.
Action
At the time, Tracer and CCX’s business relationship was at an infantile stage. The only experience CCX had with Tracer was in consigned, SMT-only, proto level assemblies used for cable testing- which Tracer was consistently turning in 1 day completely free of defects. CCX VP of Engineering and Quality Jon Westerlind called an emergency meeting to be held with the Tracer Engineering and Sales teams. Immediately, Tracer personnel could tell the method devised by the assembly shop in Mexico was not optimal and could be improved. The quality issue and turn time issue were one in the same as SMT defects were likely slowing the build purely due to touch-up or rework time. The pricing issue, perhaps the most difficult to overcome, ended up being a major driver of Tracer’s end solution. Tracer had 2 weeks to devise an assembly plan that would 1) solve the quality issue, 2) produce 10,000 units within 2 weeks beyond the planning phase, and 3) not exceed cost restraints of the project- which didn’t account for significant changeover cost related to custom tooling.
“…we appreciate the diligence of Tracer on this…”
Solution
Tracer’s team hit the drawing board immediately. The proposed solution was simple: Proper development of the fixture design. The first improvement to the fixture design was in supporting the PCBs, particularly around the DFN components better. This was achieved through a more complex geometric pattern to support the PCBs, as well as the addition of precision tooling pins to further stiffen the arrays during assembly. The second improvement was addressed by increasing number of arrays accommodated on the fixture, from 6 arrays (60 units) per fixture to 10 arrays (100 units) per fixture. The density was also cleverly increased- meaning the new fixture design, though able to hold 40 more units, was actually dimensionally smaller than the original fixture. Not only did this smaller fixture area lend itself to more consistent stencil prints and reflow temperatures and therefore increased process stability, but also the amount of specialty high temp fixture material required was less than that the prior fixture design, which means the fixtures where actually cheaper as well. Lastly for the final fixture improvement, Tracer Engineering made an absolute breakthrough by reducing the SMT process from 2 SMT line passes into 1 pass. This was possible because 1 side of the assemblies only required solder to tin the pads for CCX final assembly processes but no SMT parts actually were placed on those pads. The improved fixture design facilitated this leaned out process via milled slots which allowed the hot-air convection to gain access to the pads on the bottom side of the boards without disturbing the paste. Long in short, Tracer could practically process the double-sided assemblies as if they were single sided, which would further reduce SMT processing time over the shop in Mexico.
Click here to view the fixture design document
“…soldered and performed well…”
Results
Tracer submitted its proposal within a few days of the emergency meeting, to which the customer replied “we appreciate the diligence of Tracer on this”- Michael Dirks. The first 1000 units were processed within weeks and submitted to CCX for First Article Inspection, who reported the “samples soldered and performed well” – Jon Westerlind. As a prerequisite to winning the business, Tracer was able to beat the old supplier’s unit price by 37% and in doing so the savings on the first 10,000-unit build alone covered the $5,000 worth of specialized fixturing that was required to implement Tracer’s production plan. Over the following 12 months, Tracer produced about 50,000 units across the 5 different versions of the product. The following year, Tracer produced another 150,000 units. Tracer continues to assemble this particular product and bids on new product releases for CCX Corporation.
Statistics
| Supplier in Mexico | Tracer | |
| Price | 100% | 63% |
| Turn Time | ~6 weeks | ~2 weeks |
| Throughput | 20% | 100% |
| Customer Sales Impact | Detrimental | Catalyzing |
| Yield | Unacceptable | No RMAs to date |
Conclusion
Overall, Tracer fosters a culture of innovation and creativity unmatched by larger and more bureaucratic organizations. It seems that sometimes the traditional cost saving strategy of outsourcing to Asia and more recently Mexico for Mid Volume PCB Assembly can prove to be suboptimal.