Electronics Forum | Thu Jan 25 12:18:40 EST 2007 | wagoner
There are several smd components in our factory that don't reliably wet to solder during reflow. Paste and placement are good, but the component won't wet reliably. All of the other components on the boards solder fine, but one of these components
Electronics Forum | Wed Jan 31 17:57:07 EST 2007 | blnorman
We've had multiple issues with non-wetting components. You say only one part is not wetting? Profile won't be the culprit, if so you would have more part issues. We've used SnPb with lead-free parts for some time now, no issues. The issues we had
Electronics Forum | Thu Jan 25 16:58:53 EST 2007 | wagoner
We are using tin-lead solder. The components could be lead free components, they probably are. I will check the plating on the components and investigate changing it.
Electronics Forum | Thu Jan 25 21:49:12 EST 2007 | realchunks
Wagoner, Try switching to a transitional paste designed for no lead parts on a leaded board. Running your current paste at higher temps will dry out your flux too soon, which may be your problem.
Electronics Forum | Fri Jan 26 09:49:53 EST 2007 | dyoungquist
You should have no problem using lead-free components with tin-lead solder. Is your reflow oven IR or hot air? If you are using an IR oven and the components are white or light colored, they may not be heating up enough for the solder to flow on
Electronics Forum | Mon Jan 29 16:30:11 EST 2007 | wagoner
We reflow with hot air. Our peak reflow temp is 220 to 225 degrees C. Thanks for all of the ideas.
Electronics Forum | Tue Jan 30 04:20:26 EST 2007 | Phil J
Print your paste onto a ceramic tile, place the offending component onto it and send through the reflow oven; then observe the results. You will soon see if the component is solderable!
Electronics Forum | Thu Jan 25 13:20:17 EST 2007 | slthomas
Are you running a lead free process? If not, have you identified these as lead free components? If so, have you increased the temps in your profile to accomodate that? After that, I'd look for a AgPd (silver/palladium) or some other such PITA platin
Electronics Forum | Thu Jan 25 17:14:44 EST 2007 | slthomas
Good luck with that. ;) More likely you'll have to adjust your profiles. In our case with the palladium terminations we had to touch them up. There were other parts on the board that couldn't take more than 5 seconds at ~235 C� (don't remember for s
Electronics Forum | Fri Sep 22 09:20:57 EDT 2000 | S. REYNAUD
Hi guys !! I'm searching a method to wet etch 100 Angstr�m of an optic layer of Ta2O5, through a photo resist mask. Thanks in advance St�phanie