Electronics Forum | Mon Apr 09 20:55:46 EDT 2012 | action_101
I forgot to add that we are using a 3 mil stencil. It seems like to me that may be there isn't enough flux left when we reach liquidous?? About half of the solder spheres do melt and wet on each pad, but the top half of each solder joint is just the
Electronics Forum | Thu Feb 13 03:49:15 EST 2014 | jlawson
Yes all above is correct, as solder deposits get smaller and mesh T4+ , actual metal to air contact surface area increases , say in contrast to T3, add to this less flux , and flux running away from the joint, re-oxidation and what flux is left, can
Electronics Forum | Fri Jul 30 00:21:01 EDT 2004 | Jet
Hi, Very interesting article on tombstone issue, i'm facing tombstone issue for 0805 IDC component, i've redesign the stencil aperture and change to lead free paste, the tombstone is reducing but not fully eliminated, however there is a problem i fa
Electronics Forum | Fri Aug 11 22:50:57 EDT 2017 | heros_electronics
Anyone who knows how to prevent such flaw? Tombstones are those lifted components from one sides. This results in costly and time-consuming amounts of touch-up and re-work after the assembly is completed. For the customers, this extra work translate
Electronics Forum | Tue Mar 01 10:55:07 EST 2005 | spot
A lot depends on the complexity of the board/process as well as the amount of placements. If the board has few placements and the parts are not smaller that 0805 then doing all the rework after completion is ok. The human eye can only pick out obvi
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 May 06 08:47:05 EDT 2016 | davef
You're correct. This design will have a record amount of 0402 rework for tombstoning and misalignments. Suggest that the pads on each end of all components be the same size in order to balance wetting forces during reflow.
Electronics Forum | Sat Sep 27 13:12:37 EDT 2014 | gascon5383
I have a situation and was hoping to get some opinions on whether a saddle type profile is better or worse than a linear profile. We have an 8 heating zone 3 peak zone and 4 cooling zone single track oven that I am having a tombstone issue with. It's
Electronics Forum | Sun Aug 13 22:26:01 EDT 2017 | dawson
Anyone who knows how to prevent such > flaw? > > Tombstones are those lifted components > from one sides. This results in costly and > time-consuming amounts of touch-up and re-work > after the assembly is completed. For the > customers, this e
Electronics Forum | Sun Oct 11 16:20:49 EDT 2020 | kumarb
Hi. My 2 bits...from your list, we have had communication with Seamark and our experience so far has been very positive. We are reviewing to purchase one of their BGA rework systems, primarily from the video on youtube showing Louis Rossman running o
