Electronics Forum | Mon Oct 31 09:18:43 EST 2005 | jdengler
If the board is HASL you may always have trouble. Try to reduce the amount of paste by either reducing aperture size of stencil thickness. Jerry
Electronics Forum | Fri Jun 18 13:47:33 EDT 1999 | Jason Gregory
| Now don't everyone jump on this at once, but it seems time for me to send out copies of my not even close to being dated copy of an article about HASL. Though it was published in 1992, in Printed Circuit Fabrication Magazine, and it got rave review
Electronics Forum | Mon Oct 02 10:50:02 EDT 2006 | bradlanger
Bob, I agree that these are all board shop issues. I think the only one that is related to the Hasl process is the surface mount solerability issues. I think they are still putting the coating on too thin even though they say it is fine. This proble
Electronics Forum | Wed Nov 20 09:23:53 EST 2019 | alpha1
We had a board we fought with for a while with solder balls. Checked everything, Stencil thickness at .004, reduced apertures, changed paste 3 times, changed profile 3 times. Finally changed board vendors. Went from HASL to Emersion Gold. Problem sol
Electronics Forum | Thu Jun 29 10:38:04 EDT 2000 | John Thorup
Hello Christopher I don't know if there is any kind of official standard but I can tell you that the HADCO DFM manual specifies a nominal thickness of 50-1500u" with an option for 100-1000u" and the Merix DFM manual specifies 30-200u" Our boards (fro
Electronics Forum | Tue Jul 27 11:34:05 EDT 2004 | C Lampron
Nippy, This is exactly what we are seeing. The exessive pads are all on one side of the board. This is a 10 up panel 5x2. All of the QFP's on one side on the panel are not releasing or are not gasketing and causing bridging. So the defects are rangi
Electronics Forum | Mon Jul 14 12:55:07 EDT 2008 | arminski
I have a board with the above problem from our PCB supplier. After they applied the solder mask and run the PCB's to HASL process, the solder mask bubbled on one side of the PCB making the solder mask thickness higher and PCB looking awkward. They s
Electronics Forum | Fri Jun 18 14:06:15 EDT 1999 | John Thorup
| | Now don't everyone jump on this at once, but it seems time for me to send out copies of my not even close to being dated copy of an article about HASL. Though it was published in 1992, in Printed Circuit Fabrication Magazine, and it got rave revi
Electronics Forum | Tue Mar 20 20:14:40 EST 2001 | davef
Electroplating [electrolytic] and dipping [HASL] are the two methods for applying solder coatings to features on boards. Disadvantages of electroplating lead / tin are: * "Weak knees" created at the edge of plated through holes. [I used to get weak k
Electronics Forum | Fri Nov 09 16:58:30 EST 2001 | davef
Go for it!!! You were unspecific, but adding mask to a completed board could cause: * Increased paste thickness, if you have double thickness of solder mask. * Wrinkled and lifted solder mask under the component, if the solderability protection of
