SMART Events

OK Industries hosted the now annual Rework and Repair day on behalf of the SMART Group which as always proved both topical and enlightening. Major players in the equipment and consumable market were on hand to demonstrate the principles, and to allow the delegates a chance for some hands on experience. This lead to a day which was a good mix of the theoretical and practical for the 24 delegates.

Table top demonstrations were given by Vision Engineering, OK Inductries, Blundell Production Equipment, Cooper Tools, and Intertronics.

Simon Hawkins, Technical Manager for OK Industries welcomed everyone to the workshop and set the tone of the day by setting aside time during the seminars for the delegates to benefit from trying out the equipment brought in for the day. He also handed out CDs of the Nepcon West proceedings, and of the EPS "Rework and Repair for conventional and SMT".

Barry Morris of ART kicked off the morning session covering the IPC-A-610C guidelines on inspection. There was a good mix of visual and text which challenged some of the long held beliefs as to what makes a solder joint acceptable. When was the last time you read what is acceptable ?

Simon Hawkins discussed, with the help of video clips, the different uses of convection and conduction in reworking boards. How this will be effected by the use of a lead free regime was covered. He ended with BGA and CSP removal and rework including the joys of pasting a CSP !!

Following a buffet lunch, the equipment around the room was fired up for live demonstrations. The writer, Tom Perrett, Loctite Electronics, ran through the pitfalls of solder and flux selection, lead free soldering implications, ending with a glimpse of a future with having to rework underfills from CSP and conductive epoxies.

BGA reballing at first appears as tricky as it sounds but Keith Taylor of Intertronics lead the delegates through the justification for doing it. This included the need to be constantly aware of the dangers caused by ESD, moisture and temperature sensitivity. Then to the practical side of removing, cleaning, inspecting, reballing, fluxing, placing and reflowing.

Inspection of a BGA joint can be carried out by Xray analysis, but the complimentary method of visual inspection was the challenge taken up by Paul Cooper of Blundells. Some very clever video clips showed the double drop of the BGA as the intermetallic joint is formed, without which no solder joint is metallurgically sound. The use of visual inspection equipment to close the quality loop allowing the user to take control of the BGA assembly process.

The day concluded with Colin Turner of Vision Engineering entertaining everyone on the benefits of using microscopes where ergonomic considerations have been understood by the microscope designers. The understanding of this allows for day long use of the microscope for inspection to be possible with no loss in operator efficiency in fault detection.

The day concluded with time to look again at the rework equipment before the long journey home.