Electronics Forum | Thu Apr 11 20:35:22 EDT 2002 | davef
Messy. Messy. Messy. Consider gluing these components, until you control your process. It is unclear to us that a single factor drives these defects, but multiple factors that need to be tuned to work well together. PAD DIMENSIONS * Some SM-782 pa
Electronics Forum | Thu Apr 16 09:54:12 EDT 2009 | davef
We know virtually nothing about your process, but here's some guesses: * Turn-off the nitrogen * Change from Sn63 to Sn62 * Change to a low-tombstone paste * Change the thermal recipe: slower ramp, longer soak * Do a better job of placing components
Electronics Forum | Wed Apr 15 17:16:00 EDT 2009 | rmitchell
Hi, I am trying to reduce some 0402 cap tombstones. The main cause is the pad spacing is a little too far apart and the parts are as tall as they are wide .5mm I am stuck with the pad spacing for a while. All other parts are soldering well, even 0
Electronics Forum | Fri Apr 17 10:44:29 EDT 2009 | rmitchell
Hi, follow up, Thanks to everyone that responded. We finished the build, the sun burst thru the clouds and the birds sang. Well that was a slight exageration. Sorry for lack of detail on the original post, I was frazzled. Since the 0201's were p
Electronics Forum | Thu Dec 21 19:24:25 EST 2000 | Alejandro Rodriguez Gallegos
Hi Sorry my poor english We have some problems with some componentes 0402 we recived by the manucterer oxide in the tape reells exactly in the bottom side to the reel I think the root cause is the oxide in the tapes rells What do you think? And ot
Electronics Forum | Thu Jun 02 17:24:19 EDT 2005 | PWH
Could also be a ground plane under one of the terminations of the cap causing heat sink troubles during reflow. One pad liquifies/solidifies before the other. Don't know a good solution for this outside of reworking them.
Electronics Forum | Fri Nov 03 11:08:29 EST 2000 | Phil
Hi there!!! Actually, all mentioned ideas were significantly related to the cause of tombstoning. But, based on what DL said, you have to check the placement of your 0402. Coz, based on experience, i evaluated the different variables for the root
Electronics Forum | Mon Nov 06 10:29:28 EST 2000 | Dean Stadem
All of the replies have merit. Here is another one. Because the cause of the tombstoning is wetting forces that are imbalanced, and one end wets faster or more readily than the other, the 0402 lifts up on that end easily because of its low mass. Incr
Electronics Forum | Tue Jun 06 17:20:05 EDT 2000 | Travis Slaughter
There is no difference in 0402�s on the bottom side than 0603 0805 1206. They will not fall off or tombstone, unless they where before you put them in the oven.
Electronics Forum | Tue Dec 26 12:35:09 EST 2000 | Dave F
Your English is fine. Your assessment that corrosion on a portion of the metalization on the end of a component is causing the tombstoning is reasonable. We've seen that before. Corroded components received from a supplier is not acceptable as an
