Electronics Forum | Sun Jun 01 03:42:49 EDT 2014 | sync40
Hello to everybody in this forum, I would like to know any information that you kindly may have about the following subject: We very often do manual soldering assembly of immersion tin finished PCBs. Since thiourea is used in the formulation of the
Electronics Forum | Mon Jun 02 15:09:10 EDT 2014 | davef
I've never heard of anyone affected by thiourea during assembly soldering operations. I believe the greatest concern of exposure to thiourea is during the board fabrication process. BR ... davef
Electronics Forum | Mon Jun 02 20:38:42 EDT 2014 | davef
I believe that you get better responses when you start a new thread, but that's just an opinion, not a rule. BR ... davef
Electronics Forum | Sun Jun 01 13:25:26 EDT 2014 | davef
Eurolanders and Asians are the primary users of immersion tin. In the US, the use of immersion tin is restricted due to the concern over the thiourea that used in tin plating process. Thiourea is a suspected carcinogen. I’m inclined to say, “aww, as
Electronics Forum | Sun Jun 01 13:50:12 EDT 2014 | sync40
Thank you for your reply davef. Although the US restriction, I think that there are plenty of users of immersion tin in Americas, mainly low-volume fabs that do not plan to outsource finishing, or do not plan or can not invest in a HASL. If we res
Electronics Forum | Mon Jun 02 15:51:17 EDT 2014 | sync40
Thank you so much again davef for your new reply. This past weekend I was looking for more information regarding this subject, but, as you stated there is no information about thioruea concerns during assembly soldering operations, mainly focused in
Electronics Forum | Mon Nov 25 07:58:27 EST 2002 | Yannick
Hi, I made a board wich I plated with immersion Tin, I tought it should be the same result as we had with tin lead but we ran into a weird problem. WE use a 63/37 no clean paste and on the Board with Immersion Tin the solder just make a ball ON
Electronics Forum | Mon Nov 25 09:06:15 EST 2002 | jax
You might want to check the tin thickness. I believe you have a minimum of .65 microns in order to achieve a good solder joint through 3 thermal passes. In an immersion tin process, the ability to solder is time and temperature dependant. As the int
Electronics Forum | Wed Aug 09 08:06:07 EDT 2006 | davef
See "IPC-4554 Specification for Immersion Tin Plating for Printed Circuit Boards" 3.2.1 Immersion Tin Thickness. The most common reason for solderability issues with the white tin surface coating during multiple thermal excursions is a thin white ti
Electronics Forum | Mon Aug 07 09:04:09 EDT 2006 | molos21
Hi everyone, I am starting to use the lead free process and I had a few wetting problems (solder did not reach top side) at the wave soldering process once the pcb had passed our smt line (one heat pass). From what I understand, I have had a problem