Electronics Forum | Mon Nov 12 16:14:47 EST 2001 | davef
Yes!!! How can we assemble boards with 20 pitch when we allow 0.008� error to the master art? Excellent question!!! IPC-D-300G has nothing to do with assembler requirements. It is written by and for fabricators, so that they can be comfortable.
Electronics Forum | Wed Nov 14 20:28:24 EST 2001 | davef
Not to worry. Just run the boards through the cleaner. It will remove all the solder balls. The gross filter on your washer will collect all the solder balls. Coo eh? ;-) How to cure SM? Is your mask UV, er thermal? After learning the type, you
Electronics Forum | Mon Nov 19 20:10:49 EST 2001 | davef
We print glue with a thick stencil on one product. Although it works �correctly�, we don�t like it because the process flow is goofy. So on a high mix line, it ends-up being a burden. Also, there is no rocket science behind making the stencils for
Electronics Forum | Tue Nov 20 20:56:23 EST 2001 | davef
You�re correct. The release characteristics of epoxy differ from solder paste. Consider: * Using print/flood stroke, on-contact print cycle. * Printing slow enough to fill the hole with adhesive. * Overcoming the thixotropic [The viscosity of thixo
Electronics Forum | Thu Dec 06 15:09:14 EST 2001 | smtspecialist
Thanks for the info, Of course the first thing to do was to look with my supplier, but the problem was that it's a special relay, custom made from a design created 10 years ago. Two years ago that company went BK and we had to order a whole bunch t
Electronics Forum | Mon Dec 10 04:15:01 EST 2001 | Beny
Thanks for your advise Now I don't found Non-wetting defect at TIN COATED 0603 after I had increased peak temp and Time above 183 C. At film caps, I still found Non-wetting in high rate at film chip size 2416. I using PANASONIC's part with identif
Electronics Forum | Fri Dec 14 13:58:07 EST 2001 | slthomas
This is one I haven't seen before (not in this context, anyway). We have an assembly that we have the SMT done out of house on, because of the high volumes. The boards have two distinct characteristics with respect to the appearance of the solder jo
Electronics Forum | Wed Dec 19 01:17:13 EST 2001 | ianchan
Hi Experts, I need help here, advice appreciated from all... Production is running a Lot of flex-circuit PCB, through the SMT line, with 0402 components. The flex-PCB is taped to FR4 support "pallets" when processing thru' the SMT P&P m/c. We use
Electronics Forum | Wed Jan 09 12:20:00 EST 2002 | mregalia
Thanks for cluing me into IPC-2221. Though the numbers they give seem to contradict what I have learned from people working with the materials. At least I now know where the guideline for a max of 30 microinches of gold for soldering comes from. But
Electronics Forum | Thu Aug 29 06:48:01 EDT 2002 | yngwie
I have seen several Imm Ag pad on the assembled board which have a copper colorleaching through the silver plating This happened on the pad which was not deposited with paste during the assembly process. Don't know if it is a problem, but we only
