Electronics Forum | Thu May 05 09:50:29 EDT 2005 | patrickbruneel
Hi Hannu, You just gave a very realistic and practical view of the lead-free dilemma. The main reason that your coil coating doesn't get removed is because of the inability of lead free alloys to wet the surface and conduct the heat. Higher temperat
Electronics Forum | Thu Mar 30 08:48:37 EST 2006 | russ
So you have solder balls at the outer edge of the part right where the pad goes underneath? If so you just have too much solder but I wouldn't worry about them. the solder usually does not wet to the edges of these parts because of the exposed copp
Electronics Forum | Thu Jul 05 17:10:29 EDT 2007 | arun2382
Thanks all! I'm facing this issue with one specific batch of QFNs. It could be a plating issue. But, nothing was evident from visual inspection,No sign of voiding or non-wetting. Cross-section images of solder joints were clean as well. Could this s
Electronics Forum | Wed Jul 19 12:54:04 EDT 2023 | calebcsmt
Since side fillets are not a requirement for QFNs/BTCs due to some packages not having wettable side terminations, how does one determine if the side terminations are actually solderable/designed for wetting? Is it simply if the side terminations
Electronics Forum | Tue Aug 22 14:52:55 EDT 2000 | John Thorup
Jax - absolutely right - the archives are a valuable tool and deserve to be used more than they seem to be. Caumel - Are your blobs on the solder side or the component side? Are your vias tented on the component side? What size are your vias? Is th
Electronics Forum | Sun May 28 08:21:52 EDT 2000 | Sal
Can't agree more than moving over to Homebase apertures, But ensure that the cut back angle is correct,to acute of and angle will leave you with an inadequate contact area fot the terminations on the chip components and you will start seeing insuffic
Electronics Forum | Wed Sep 30 20:56:31 EDT 1998 | Tony Barry
Assuming that your components and PCB's have good solerderabillty and are stored in an air conditioned environment and kept free of contaminants then your problem sounds as though there is insufficient wetting of the component leads due to low temper
Electronics Forum | Sun Nov 24 10:12:44 EST 2002 | kcorrin
Thanks for your response Dave. I did look at the bare boards after wave solder and they seem to solder fine in that process. I do not see any soldermask bleed on bare boards. Regarding "thin" plating...I have had issues in the past when the board sup
Electronics Forum | Fri Oct 14 09:21:36 EDT 2005 | lupo
According with temperature vs. wetting force diagram 245-250C/degrees is better, so lower temperature than 500F means better solder fill. If the speed is too lower the solder suck out form the hole. Usually 120-150cm/min. is good. (2-4s contact
Electronics Forum | Tue Oct 21 11:42:04 EDT 2008 | arosario
Hi Shooter, we're not using AOI but we do every 30 minutes sampling Inspection on the board and we're not seeing insufficient paste deposit so far since we started. But I agree with you that seemed my printer is not printing consistent amount of pa
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