We are a local enterprise with limited resources, just like you described, so hope this experience sharing helps :
we place a production Visual Mechanical Inspection (VMI) inspector at the end of each Reflow Oven area, complete with magnify scope 30x and a cutie spacious table, with instructions to nothing but inspect each and every pcs of PCBA output from the Reflow Oven. We do this 100% in-process(aka.= IPQC) inspection for both 1st and 2nd SMT processes' output pcs.
All the IPQC data is entered into a excel spreadsheet, by SMT supervisor on daily basis (yesterday output, today we data entry into excel), as this keeps the SMT guys accountable for daily monitor of quality performance and blowing the whistle to QA, Process, Technicians for help instead of running like nobody's business and then asking for conditional quality waive just before shipment.
The data is analysis by QA Engineer, who will ask the Technicians and Process Engineer for immediate action on critical defects (eg. crack components). This portion is tricky coz different companies define crtical defects differently. I suggest anything that is potential "market claims" or "difficult/intermedient to ICT/FT detect", becomes a critical defect. Finetune your inspection and testing requirements along customer contractual requirements. If the customer is doing the testing and all you guys is build the PCBA boards, then just stick to mechanical visual inspection processes.
More acceptable "inherently design/machine" process defects (eg. insufficient solder, missing components) will have engineering root cause study, proposed remedy action to either customer(design/materials fault) and internal management(machines/manpower/method fault). give your management and customers a solution together with the fault analysis, else you will get F' big time...
Inspection data must be collected (initial stage at the very least) to know what defects are happening on each (1st/2nd SMT) sides of the PCBA, and at what severity rate?
Only after knowing what defect location, types of defect, and frequency, y'all looking at can you form an effective "counterstrike" program against output defects. (that program however is another story).
On a personal level, agree that rework is not supposed to be inherent for IDEAL cases. unfortunately we do not live in IDEAL world(s). Therefore effort must be put into studying and getting appropriate parties to do their respective jobs well to minimize the screwups to SMT processes. (follow the fish-bone diagram basis of machine, manpower, method, materials, environment).
Its a tough job, yeah I know, thats why you were hired to be the smuck... take pride in being that "great fella who's gonna make it all right"... forget about knocking heads with the opposition party, either :
1) assign them out of the team (if you have that authority) and stick with your cheerleader (similar-mindset) folks,
2) else you can force feed them to accept and just do it(again, if you have the authority),
3) else you can ignore them and go ahead without them full steam (if you have no say and authority) eventually you can show em' you did it with your supporters (lonely though),
4) else you will have to bribe, lie, cheat, smooch your way into their hearts to accept and do it your way.
Been there, done it all, and heck proud of what we achieved as a TEAM. What a interesting job we do, eh?
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