Electronics Forum | Fri Nov 08 14:19:59 EST 2019 | dwl
You can try putting titanium stiffeners on the PCB to prevent it from warping. How thick is your stencil? More paste would give you a wider window however too much and you risk bridging. You could try over printing the pad at the heel and toe to get
Electronics Forum | Fri Nov 08 14:45:12 EST 2019 | charliedci
Appreciate the input from everyone. The PCB is .062" thick. As a CM we are at the mercy of our customer at this point although (hopefully) they are receptive to advice on the next build. Titanium strips could be an option, I also thought there might
Electronics Forum | Fri Dec 27 16:12:54 EST 2019 | anteiv
thank you for reply here is picture of the board https://imgur.com/a/i2MfFBw on the bottom are pins/components which height is about 3-4 mm from bottom of the board we had to increase distance of board from nozzle to make clearance and we increas
Electronics Forum | Tue Jan 07 02:04:45 EST 2020 | robl
Hi Mikey, Your signal pins (2 & 3) for USB1, 2, & 3 are all connected together so there is no way of splitting the incoming signals from the 3 ports. Normally there would be an IC (a USB hub controller) switching between the signals so that the PC
Electronics Forum | Tue Jan 14 11:39:51 EST 2020 | avillaro2020
Thanks Robl. I’ve contacted samtec followed their advice but ended up empty handed. Originally my stencil thickness is 6 mils, samtec stressed the need for the paste and charge to have good contact but this is challenged by the inherent charge non-co
Electronics Forum | Tue Jan 14 17:22:16 EST 2020 | emeto
Avillaro, would you say that vapor phase process was selected, because the boards are so thick and heavy? I would assume so. Have you ever tried to run them through reflow oven? To understand better your challenge, we need to understand the setup be
Electronics Forum | Wed Jan 15 10:31:55 EST 2020 | emeto
Having 10c thermal differential is a lot. Trying different paste might help - usually thermal expansion makes component detach from PCB, then joint is formed and solidified, then component goes back but is too late to form a joint. Cooling speed migh
Electronics Forum | Fri Feb 07 20:41:52 EST 2020 | orbitcoms
I am finding if I have to stop the pick and place machine during production very often (mostly due to feeders not pulling the tape cover back), I get paste drying in the apertures of the stencil. To avoid this I am thinking of pasting all the boards
Electronics Forum | Mon Jun 29 16:03:24 EDT 2020 | spoiltforchoice
I certainly can on the Paraquda and I suspect the basic algorithms are the same. Slimmer annular rings such as you might get on a plated via hole don't always image quite as well but if for some reason it doesn't pick it up you should be able to inte
Electronics Forum | Wed Jul 29 21:16:17 EDT 2020 | SMTA-64387706
Hi, I have a PCB that works fine when tested before conformal coating with HumiSeal 1B73. It seems like the CC is causing electrical issues. We brush it on, so it is a bit thick. After curing we are getting QFNs that do not seem to connect well and a
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