I stripped the entire board because I had to have the boards troubleshot. Had a high failure rate from the field.
The board coating was applied about 5 months ago. I was told by my people anything past 3 days and you will need this type of stripper as opposed to our "common" stripper.
I used a closed container to prevent evaporation. However I did use a plastic container which in hind sight may have degraded in the solution and changed the outcome.
I chose liquid becuase i wanted to get under the ICs and I wasn't sure if gels would does this as well as liquid. I also thought about agitating the process and liquid seemed like the better choice.
The type of water I chose was un-informed. A call to the manufacturer would settle that issue for you.
An operator need very little knowledge or experince but must be someone who has attention to detail and follows instructions very well.
Ventilation was easily achieved with a small fan. I worked in a janitors closet about 5ft by 4 ft with an open door and a fan and felt no ill effects. However eye protection and hand protection would be necessary to avoid irritation from splashes.
The room temperature I was operating at was about 70 degrees F.
I did not study any temperature variance effects to the process. One could assume that if you raised the temperature the process would be faster and so would your rate of evaporation. However like I said, I did not partake in that study.
What I meant by shine/coat is the clear coat had been stripped from the laminate. The PCB had no shimmer anymore but a dull flat color. This was due to the amount of time I left the board in the solution. It did not have anything to do with the agitation.
Less PCB meant the shine or clear coat seemed to be stripped as well as the conformal coat. The PCB also appeared "blotchy". Again this was due to letting the baord soak too long and it also could have had something to do with the plastic container I was using. It was all I had at the time and the customer was pressing hard for us to solve the electrical defect witnesses in the field.
The solder mask, component leads, and copper traces were all seemingly unaffected by the stripper. But like I said some cheap tin alloy looking though-hole connectors appeared to have a film gathered around them. However that may have been a chemical re-action with the metal or maybe the plastic container and the metal or the PCB... I just dont know with all those variables.
The cleaniness of the stripper in coomparison with repeatability or useage was another step I didn't look into. I did five boards to find the electrical problem. Now that the problem is solved I will be removing the conformal coating from just one 8 pin SOIC.
Hope that helps a little more. If i had the time or resources I would have done something more controlled and indepth but teh circumstances dictated a fast result not a proven process.
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