Electronics Forum | Mon Aug 25 18:24:25 EDT 2008 | dyoungquist
The problem is occuring on more than one part # of our 0402 components. That is why I am looking at the reflow oven process very closely.
Electronics Forum | Thu Aug 28 11:13:53 EDT 2008 | janz
Have you tried to run the same process but with diffrent solder paste manufacturer.? This give you information whether paste is ok. Try also print paste on the bare board and run through reflow oven. Check 2-3 boards. Is it the same places where i
Electronics Forum | Wed Aug 27 14:38:20 EDT 2008 | rgduval
Does your paste provider recommend a TAL? For the leaded and lead-free pastes that we use, the manufacturer recommends 60 seconds above liquidous. I note that your profile shows the TAL as 30 seconds, which may not be sufficient. That said, tho
Electronics Forum | Mon Aug 25 16:26:52 EDT 2008 | wrongway
every time that i have seen that kind of problem where I work it always seems to be a problem with the parts having comtamination on the leads is it just one part # giving you problems our all 0402 parts on that assy having problems if its just o
Electronics Forum | Mon Aug 25 15:40:58 EDT 2008 | dyoungquist
I am seeing poor quality solder joints, mostly on 0402 components. The problem is that while the pad on the pcb is getting fully wetted, the solder is not flowing up the sides of the 0402 component, i.e. the 0402 lead is somewhat de-wetting. The re
Electronics Forum | Sun Sep 28 17:14:53 EDT 2008 | ronsou
small pads like 0402 tend to get hot quite > easily. looks like excessive heat is your problem > here. pads are wetted, component leads are not. > this means solder paste flux on top layer was > exhausted before entering in reflow. your profile
Electronics Forum | Tue Sep 02 15:29:36 EDT 2008 | bvdl
small pads like 0402 tend to get hot quite easily. looks like excessive heat is your problem here. pads are wetted, component leads are not. this means solder paste flux on top layer was exhausted before entering in reflow. your profile is the 'in-be
Electronics Forum | Mon Dec 15 15:34:17 EST 2008 | dyoungquist
Sorry it has taken me so long to respond. I got pulled off onto other projects and was not able to work on the solution to the problen until recently. The solution we have come up with is to change from no-clean flux based solder paste to water sol
Electronics Forum | Thu Feb 24 11:02:29 EST 2000 | mark scheunemann
I am looking to discuss 0402 issues, specifically tombstoning/unsoldered. Any recommendations on pad size/spacing, stencil design etc would be helpful. Placement and reflow profile look good.
Electronics Forum | Thu Feb 24 11:02:29 EST 2000 | mark scheunemann
I am looking to discuss 0402 issues, specifically tombstoning/unsoldered. Any recommendations on pad size/spacing, stencil design etc would be helpful. Placement and reflow profile look good.
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