June 17, 2002

48 Rotchild St. P.O.B 277 Rishon Le Zion 75200, ISRAEL
3905 National Drive, Suite 270
Burtonsville, Md. 20866

Dear Sirs,

In all my years in PCB assembly, I have never seen such an enthusiastic response to a training program.

Like many plants, we've been fighting board defects continuously, as Elamex and now as Plexus. Although we made progress on our own, until now we never got rid of the constant headaches our through hole lines gave us. I can now see that there really is no reason to have higher defects from wave soldering compared to our reflow ovens.

Other vendors never really could improve our problems like you have. Chemistry suppliers recommended new fluxes or solder. Wave machine manufacturers suggested numerous machine upgrades. And thermal profiling companies always suggested more and more and better and better thermal profiling for our wave machine.

From you we've learned that temperatures are not the most important variable in our process. At the same time, our Optimizer's Thermal Sensor Card does the job accurately and easily compared to regular thermal profiling. It's much more suited for wave soldering. What you showed us, in only a few hours at our wave machines, is that almost all of our defects are being caused by how our boards go through the actual solder waves.

In fact, your Instructor was able to show us that one of our recurring board problems, skipping and insufficients, has nothing to do with preheat temperatures. With measurements taken with our Optimizer, he suggested adjusting immersion depth and dwell time to eliminate this problem entirely. We now have documentation in place to address this problem if it ever resurfaces in our other boards, and specific procedures on how to ensure that these defects do not trouble these boards again.

This training has put us on the path to continuous improvement of our board quality. This will save us large amounts of money and strengthen our relationships with our customers. Thank you.

Sincerely,

Luis Velazquez
Engineering Manager
Plexus Electronic Assembly
Juarez, Mexico