Electronics Forum | Fri Nov 16 08:46:30 EST 2007 | jdengler
For very simple boards, 2 layers lightly populated with light thermal mass, we still use FR4. For most of our Pb-Free boards we use the higher Tg material with moisture-resistant packaging. We are a CM so we don't usually get to change many of the
Electronics Forum | Thu Apr 26 16:47:52 EDT 2007 | Cmiller
Is anyone using standard FR-4 material for ROHS? All I have ever seen to indicate the need to go to a high tg/td board is that the material may fail after repeted rework. I have a customer that is trying to use IS-410 and it is causing electrical pro
Electronics Forum | Fri Nov 16 08:33:46 EST 2007 | rgduval
For RoHS assemblies, we're spec'ing at least FR-406 for the higher Tg. We're currently requesting our customers to use ENIG finish, as we've had better luck with assembly in our process; but we're currently experimenting wtih lead-free HASL. As far
Electronics Forum | Wed Jan 11 12:37:06 EST 2006 | Amol Kane
Hi all, hope everyonein the forum id doing fine and working diligently toward RoHS capability. One of my customers have asked me (my company) to recommend a lead-free laminate. us being a CEM, have no idea of design variables (df, dk etc., (process v
Electronics Forum | Thu Jan 31 09:08:27 EST 2008 | glezfl36
Since the implementation of the ROHS process in our Company with the higher temp requirements, we had observed an increase in problems related to delamination in the PCB's. Actually we are using FR408 and Gracescore materials and are changing to a Ve
Electronics Forum | Tue Feb 03 03:35:30 EST 2009 | sachu_70
Hi Jose, such a process is possible, but you need to confirm that the PCB material has high Tg. In additon, you need to re-look solder paste printing parameters and make required changes in stencil apperture design for optimum solder volume. Just a
Electronics Forum | Mon Nov 19 19:14:07 EST 2007 | jmelson
I've been running 90% lead-free (still have a couple components I can't get reliably in RoHS compliance) with a peak temp of about 238 C, on standard FR-4 boards. The only real problem is the pad adherence is compromised, making rework of the boards
Electronics Forum | Mon Dec 08 17:06:59 EST 2008 | boardhouse
Hi MGL, Couple things to ask, have the boards recently been changed to Rohs builds? STD FR4 to High TD Laminate. Check the stack-up the board houses are using. Just about all Rohs laminate has Resin starvation issues when used in single ply co
Electronics Forum | Sat Nov 17 18:29:02 EST 2007 | bbarton
Let's face it guys...in most cases (stress the MOST!) a typical FR4 board will do the job. Few layers, low copper, not too densly populated etc...no worries. Use a reflow profile which avoids the 245-250C range, use a shorter TAL, Viola you have a go
Electronics Forum | Sat Nov 04 21:30:15 EST 2006 | Ola
Well, I can't tell you what the "glass wicking failure on PCB" are but for a standard FR4-pcb the Tg temp. or the so called glass temp. is 176 celcius degr. This means that the pcb is in between a firm and a buoyant condition. This is really a bit of
