Doug Pauls

Principal Materials and Process Engineer

Collins Aerospace

Doug Pauls has a bachelors in Chemistry & Physics, Carthage College, BSEE, Univ of Wisc Madison. He has 9 years working experience for US Navy - Materials Lab, Naval Avionics Center Indianapolis. 8 years Technical Director, Contamination Studies Laboratories. 11 years Rockwell Collins Advanced Operations Engineering.

Doug Pauls has submitted responses to the following questions.

Full Aqueous Clean or Local Spot Clean
I have seen far to many cases where local cleaning is not a removal of residues but a re-distribution of ...

Contamination From Anti-static Foam
Many of the pink poly materials from that time era were doped with various amine complexes to provide the static ...

What is the IPC Definition of Uncommonly Harsh?
Uncommonly Harsh is anything greater than 10% more than Commonly Harsh.

Cleanliness Standards for Electronic Components
There are no present standards for how clean a component has to be to have long term reliability, either in ...

Removal of Coatings from PCBs
The best way to remove conformal coating depends on the coating that is to be removed, how hard that coating ...

Conformal Coating Press Fit Connectors
First, IPC-A-610 is not a requirements document. It is a visual acceptance document. Requirements would come from J-STD-001 or the ...

Question About J-STD-001
The short answer is yes. J-STD-001, in both the present Rev E and the proposed Rev F (nearing finalization) there ...

Mixing Silicone and Acrylic Conformal Coatings
Is there a compatibility problem? O yes. Acrylics and silicones do not mix well. It is going to be difficult ...

Conformal Coating Recommendation
It depends on how much access the humidity has to the electronics. If you are talking about humidity, and humidity ...

Coating Scored Panels Prior to Separation
Well, the answer to this, like any good engineering answer, is "It Depends".What coating are you using and how does ...

Conformal Coating Over Heat Sinks
In my opinion, yes, you should mask the heat sinks. Each conformal coating will have some impact on heat flow. ...

Deionized Water Sample Testing
Keep in mind that deionized water, cleaned to high levels, is a very hungry solvent and will pull in ionic ...

Can Solder Joint Geometry Change Resistance?
I doubt that the solder joint or its shape has anything to do with your leakage currents. I have only ...

Syringe Dispensed Solder Paste for Hand Soldering
I would only use a syringe to dispense solder paste in applications where the volume of paste was not critical, ...

Flux Oozing from Insulated Wires
I would bet you are using stranded wire. When you flux the wire, capillary forces pull the flux far up ...

Conformal Coating in Low Humidity Environments
I will give you my favorite engineering answer - It Depends. What do you mean by"low humidity"? And what conformal ...

Bromine Free PWBs
Bromine complexes, primarily tetrabromobisphenol-A (TBBA), has been used as a flame retardant material for many years in laminate materials. The ...

Cleaning with Sodium Bicarbonate
That gets an "It Depends" kind of answer. Whether or not you have long term reliability issues depends on the ...

Concerns Using Hand Sanitizers
I did a study on this topic a few years ago. It was published in the IPC Apex proceedings. The ...