Electronics Forum | Thu Jul 31 23:52:12 EDT 2008 | roc2x
Hi, Im having problem on tombstone, The part is LF chip component 1005, and my solder paste is WS leded. tombstone is not in a deg angle but one side is soldered but the other side is just sitting on the solder. Looks like my solder can not wick up t
Electronics Forum | Fri Aug 01 02:10:26 EDT 2008 | fowlerchang
Pad design is not only the size of pad but also the distance between two pad. N2 will increase tombstone as we tested. 10 zones reflow oven and slow temperature ramp will reduce this defect. MustII is the equipment which is used to test the solderabi
Electronics Forum | Fri Aug 01 00:40:06 EDT 2008 | roc2x
thanks,my pad design is 24 x 23 mils and now I chnged my stencil to 24 x 20 mils ship inwrds to lower down my volume. My placement is and part data are ok. My reflow N2 is using 1000ppm, Actual is 700-800ppm I already prolonged my pre-heat butit only
Electronics Forum | Fri Aug 01 00:22:46 EDT 2008 | fowlerchang
Pattern design, paste volume,printing misalignment, place misalignment,reflow process include N2 usage. All the factor above can make tombstome happen. And the most important factor is placement misalignment except design issue. But pls check the sol
Electronics Forum | Fri Apr 04 14:49:51 EDT 2008 | tombstone
Flux seperation is a common problem observed due to expiration of paste. The symptom is a yellow layer of flux when you open the jar. Excess flux separation will cause priting problems such as smearing and slumping.
Electronics Forum | Tue Jan 17 17:29:42 EST 2006 | pjc
Here's a page on tombstoning: http://www.tkb-4u.com/defects/reflow/tombstoning/tombstoning.php Be sure to see this on the bottom of the page: For more info about this item look at the Articles / Newsletter: (Causes and Cures of Tombstoning Chip C
Electronics Forum | Tue Nov 29 14:57:45 EST 2011 | jlawson
Sorry on N2 and tombstone, many other aspects cause tombstones and n2 in itself does not cause tombstones. It can help make other bad variables tip over edge to cause tombstones more than with no N2. Get these right then N2 is not issue.
Electronics Forum | Thu Sep 10 19:26:24 EDT 2020 | emeto
Are parts always following the same side/direction of tombstone? 1. Run 180 and observe if tombstone moves or remains the same 2. Too much paste under the part - reduce aperture and move it out to the lead. 3. Soak profile for even heat distribution
Electronics Forum | Tue May 09 14:23:40 EDT 2006 | flipit
I would like to know what you are seeing in production. I have read the papers that state fewer tombstones with SAC305 as well as the papers that state more tombstones with SAC305. I am seeing more tombstones with SAC305. I place a lot of 0402 com
Electronics Forum | Thu Feb 18 21:17:35 EST 1999 | Barbara
What to look for that causes tombstoning and the corective action.
