Tod Cummins

Tod Cummins has submitted responses to the following questions.

Matte Black Solder Mask Defects
Currently running several thousand assemblies annually with black mask. I am unaware of any masking defects to date. These are ...

Oxidation of Solder Balls During Secondary Reflow
Hope I am reading this correctly - if the solder ball flowed properly during the 1st reflow, then no it ...

SOT (Small Outline Transistor) Body Cracks
Pretty vague description of the issue. Some areas to look would be moisture if the boards are going through a ...

Mixed MSL Baking
Need a little more information regarding the situation. E.g. what type of rework is going to be performed (hot air, ...

Pick and Place Machine Calibration
Calibration of Pick and Place equipment really depends on the type of equipment being used and manufactures recommendation. Throughout the ...

Baking After Cleaning Hand Placed Parts
If a part is being placed by hand, instead of SMT due to moisture sensitivity, then it is been placed ...

Hand Sanitizer Contamination
Not sure on this one, would need to conduct a DOE to determine. However, I have advised to use caution ...

How to Remove Oxidization from SMT Component Leads?
From a soldering standing point if the components need to be retinned, then Google retinning electronics components and there are ...

Causes of Annular Ring Dewetting
Need some clarification and possibly pictures if possible to accurately advise. In my experience actual dewetting has almost always been ...

Shelf Life Limit for Soldering Old Components
Component shelf life is really an OEM specification and I would expect the OEM to determine shelf life based on ...

Pad Missing ENIG Plating
I suggest maintaining the original ENIG is the required finish. While the skipped pads are all that appears to be ...

Cleaning Under Low Clearance Components
We place thousands of the leadless components with center thermal pads that would be considered low clearance. All done with ...

Moisture Sensitivity Level for Bare Boards
We do not include PCB's in the MSL program. JSTD-033 is specific to surface mount devices. We do have a ...

Specific Solder To Control Dendritic Growth
Generally what I see is solder type is recommended, not specific brand or part number. However, I do run across ...

IPC-A-610 Class 3 - IPC-A-600 Class 2
In short - yes you can have a class 2 PCB and class 3 PCBA. Keep in min that both ...

Two Year Component Date Code Mandate
I have run into this requirement for a couple of customers over the years, however I have not seen it ...

Recommended Fiducial Shape
What type of equipment is rejecting this as a fiducial? Possibly a plus symbol (+) would work if your equipment ...

What Is This Contamination?
Very difficult to determine the cause from the pictures provided, however there appears to be a conformal coat or potting ...