However, PA (also known as Nylon) has the attitude of gathering humidity. These are products that have either an LCP (Liquid Crystal Polymer) housing and can easily be used in any lead-free reflow process or they have glass-filled PA insulators, which are typically capable of running through a reflow process. Already years ago, Molex defined products as Surface Mount Compatible. When it comes to temperature stability of plastics during the reflow processes, the situation gets even more complicated. The above is only considering the solder processes themselves. Note: THR = Through Hole Reflow, also named PiP (Pin in Paste) or PiHR (Pin in Hole Reflow) There are other mixed solder processes which use both – wave and reflow – for one board: Note: THT=Through Hole Technology | p&p=pick & place | SMT = Surface Mount Technology Standard are single layer and double layer pure processes (wave solder or SMT reflow): So, knowing the solder process is key for every connector sales person as well as for every user of connectors, here is an overview of various solder processes. We investigated movements of microminiature components during reflow soldering which reminded me of some Hollywood movies taken in a crematory. In this case we had to explain the difference between solder temperature and heat resistance, although clearly indicated in the product specification. I also saw melting housings, which let the pins drop down when another customer changed from lead to lead-free soldering temperatures. Make sure to use only products with nickel underplate of the tin plated leads in a lead free environment. I survived cases where the customer reduced the lead-free wave solder temperature to prevent melted pegs underneath the board (and created un-sufficient solder joints). Is it wave solder? Is it SMT reflow? Does the customer prefer pin-in-paste? Molex tries to explain a lot on the web – either in the product description or in the product specification – however, when it comes to lead-free solder processes (>+250☌ for 5 seconds) it is key to know the process in detail. The answer to this question gives me choices and prevents me from recommending the wrong product. That is why one of the first questions I ask, when it comes to the connector choice is: In most cases, application of a connector has to do with soldering (except crimp and IDT connections).
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