Hello :). I have some of these Molex 1054440011 USB-C edge connectors/plugs of that I somehow don’t know what’s the best way to assemble them onto my PCB.
I have the pads (standard layout from the datasheet drawing) exposed on the stencil but the pins push the paste away a little so I had quite an amount of solder bridges to rework after reflowing them. Could probably a little less solder paste (so smaller openings) and/or differently shaped stencil openings help? Also there are pins (and other components) on the backside so it’s difficult to apply paste accurately on both sides. The pins are additionally a little weirdly shaped (they bend upwards at the ends so it’s easier to push the PCB between the pins) what makes them less accessible with a soldering iron and the 0.5mm pitch doesn’t make things easier. At least the tension of the pins holds the connector in place while reflowing.
This specific one will primarily only be a one (or two)-off prototype board so I could life with some reworking but maybe someone around here has experience with these things. I also wondered how something like that would be assembled in a larger scale, the pins hold the PCB quite tight between them, I can’t imagine a pick-and-place machine could handle that.
Thanks for reading this post and maybe you have some answers :).
Solder has very strong surface tension forces, when very fluid. So, if there is lots of flux gel present between the pads, and the bridge is broken only momentarily, the solder will draw back to create the minimum surface area on each of the pads. It’s almost unbelievable to see, when it happens.
Almost all of my small workshop hand tools are stainless steel medical ones - the local Government Surplus Depot sold off warship’s “First Lieutenant’s Surgery Kit” and I bought one. Then went and got another one. They have this scraper tool that just needs to be drawn across the solder bridge and the solder snaps back to the pads.
It does need the area to be flooded with zero residue flux, though. Which both helps the solder to be really, really runny and follows the tool, so that the gaps are filled with flux.
I only have very runny liquid flux here but I did just order some gel “tack flux” and give that a try :).
I did just get the gel-flux I ordered (Chipquik SMD4300TF10) and it worked pretty well, didn’t expect that it makes that much of a difference :). See the other comment for a picture if you want, I didn’t want to spam it everywhere :D.