Electronics Forum | Thu Dec 14 19:32:05 EST 2000 | Dave F
Wow, someone read the fine SMTnet Archives!!!! Scary, get their name!!! [OK, I�ll stop ... Several points are: * Most of the stuff in the fine SMTnet Archives is all the bad things that we can make-up to respond to the questions people ask. Ther
Electronics Forum | Wed Mar 16 15:52:41 EST 2005 | cyber_wolf
Are you using a standard convection reflow oven ? This does not make any sense. I have never heard of anything like this. If you are using a standard oven, then I would say that it is time to get your profiler calibrated.
Electronics Forum | Thu Mar 17 12:51:39 EST 2005 | Slow Ride
How much more? A couple degrees? That would be normal from one board to another, depending if the t-coupls are in the exact same spot etc. What type oven? IR ovens can be affected by colors.
Electronics Forum | Thu Mar 24 15:29:46 EST 2005 | Claude_Couture
other than the fact that silver is a better conductor of heat, I can't think of anything.
Electronics Forum | Thu Dec 14 12:18:01 EST 2000 | genny
Hello all, Our company has always used HASL finish on our products. Recently however, we have a had a problem on a couple of boards that I have been told cannot be avoided with HASL, and we should switch to ENIG(electroless nickel immersion gold).
Electronics Forum | Sun Jun 06 09:20:03 EDT 2004 | michaeljm
My department and I have been working with immersion silver on and off for about four years and we have compiled quite a bit of data for the Alpha and MacDermid immersion silver chemistries. We have not encountered any assembly or storage related is
Electronics Forum | Thu Mar 24 13:29:50 EST 2005 | chunks
3-5 degrees between two different boards is not that great a deal. It could simply be a combinations of the t-couple and where/how it's mounted on each board. It could be related to the metal or it's thickness, depending on your layout. Over all,
Electronics Forum | Fri Dec 15 13:57:46 EST 2000 | genny
It is only after the reflow heating process that the peaks may show up, as the solder build up in some vias(due to HASL'ing) might drip down during reflow. I don't think I've ever heard of it being desirable to have a bare copper surface that will ox
Electronics Forum | Wed Mar 16 20:11:03 EST 2005 | darby
KT, What sort of delta T are you getting? This does sound a bit odd. TCs are in EXACTLY the same position on each board? Something I only recently found out - according to Mark Cannon from ERSA re profiling, that you may wish to consider. 1.TCs sho
Electronics Forum | Thu Mar 24 07:06:06 EST 2005 | davef
There's a lot of comparison tables on the web. Here's one: Properties - Summary [A Winlow Circatex] Attribute||Hasl||Immersion Silver||Immersion Tin||Electroless Pd||OSP||Eless Ni / Imm Au Shelf Life (months)||12||12||12||12||12||6 Multiple Reflows
