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PCB Washing No Clean

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#64537

PCB Washing No Clean | 24 June, 2011

My company is currently looking for a closed loop system that we could use for batch washing of PCBs. We primary use no clean flux and are looking for a system that we can use to clean the residue? Most likely we are going to have to add an additive like Alpha's 2110.

Any recommendation that you can provided would be greatly appreciated.

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#64539

PCB Washing No Clean | 24 June, 2011

You should look at Amtech Solders. They have excellent no-clean fluxes that are designed to be water washable if desired. We have been using them with great results for about 4 years now.

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#64541

PCB Washing No Clean | 24 June, 2011

I am going to open the flood gates of comments. The purpose of no clean is so you do not have to clean it. Yes I am aware of no cleans that you can clean. If you need to clean the boards use a water soluble paste. If you do not clean, no clean properly you can cause even more contamination on the board. Now back in the day for you old timers cleaning boards was not a big deal with the old style vapor degreasers until we found out it was destroying the ozone layer.

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#64545

PCB Washing No Clean | 27 June, 2011

I fully agreed do not CLEAN the NON CLEAN process. However, some customer may request to clean the non clean process; and they willing to pay for it. In order to clean the non clean processes (the residual on the board), you need to consider the compatibility of your Non Clean chemical used. The best way were first understand your non clean chemical characteristic, then select some chemical cleaning supplier (you can get a lot of supplier from web search, I do not mentioned here as I am sale person from any of this company and do not tried to put wrong comment of certain cleaning product). After select the cleaning chemical then you need to perform first level evaluation to find out the cleaniness of the assembly after wash (some supplier may claim they are so effective but in reality it is not).

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#64577

PCB Washing No Clean | 29 June, 2011

Let's be more specific. Why do you need to clean the boards? I assume it is for testing purposes, probe contact concerns and the like. This is the only economical reason I can think of to clean no-clean flux residue from your assemblies. Before you go the route of a glorified dishwasher, what changes have you tried in your process? Have you tried changing the preheat temperatures of your wave? By increasing the temp, you can burn off more of the residue. The problem we had with this is, it worked great for one assembly, but then we started experiencing solder shorts with others. You may find a happy medium. Another solution would be to change your flux to something more ICT friendly. We experimented with Kester's 977 low-residue flux and had pretty good success. You might want to try that first.

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#64586

PCB Washing No Clean | 5 July, 2011

Hi Bill,

I agree with not cleaning the no-clean. If you're looking for a cleaner because one of your customers is requiring no residue be left on the PCB's, I'd investigate switching to a Water Soluable Process for those specific assemblies. (You'll need to enforce strict process control, but you're already doing that with your leaded and lead-free pastes. As far as a cleaner, I'd be very careful shopping for a used cleaner. Most of the older Batch Type cleaners on the used equipment market are no longer supported. I'd check with the machine manufacturers first and make sure that whatever used machine you find is still fully supported. (I ran into this when I chased down this Wild Goose a few years ago when I held your job)

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