Electronics Forum | Thu Nov 15 07:59:53 EST 2001 | John S
My company is in the process of evaluating dispensing/screen printing vendors for a new production line that will build a mixed through hole and smt board in high volume. DEK recently came out with a system that uses a thick plastic stecil with mach
Electronics Forum | Mon Nov 26 20:15:50 EST 2001 | davef
Sounds like you are thinking correctly. I'd guess your fab has gotten "smart" and changed your bare board, as you suggest. So, you've got two choices: 1 Rework the QFP. 2 Remove the lower temperature PTH components and solder them to the board some
Electronics Forum | Sat Dec 01 09:12:27 EST 2001 | davef
Ah, there�s the rub. So often we see scoring requirements defined based on depth of cut. This ignores that the depth changes with a variety of factors, including: * Wear on the cutting blade. * Variation in thickness of the fabricated board. So, c
Electronics Forum | Tue Dec 11 18:32:30 EST 2001 | edmentzer
Does anyone have experience with different colors of solder mask. I am interested to know if a clear or light color mask is better in the reflow process. Most of the boards we do have a green solder mask. It seems to me that I read somewhere that
Electronics Forum | Mon Dec 31 09:00:06 EST 2001 | davef
Baking before assembly does nothing good. It: * Increases costs. * Adds steps to the process and makes scheduling more cumbersome. * Increases the amount corrosion on solderable surfaces. We used to bake to remove the moisture from boards that caus
Electronics Forum | Mon Dec 31 08:59:36 EST 2001 | Don Adams
The second pass in the wave is pretty extreme and will probably aggravate the conditions which caused warpage in the first place. Areas to look for problems, The lay up of the boards at fabrication or the materials used can lead to warpage. Work wi
Electronics Forum | Wed Jan 16 15:13:24 EST 2002 | dougt
The Industry has just come out with some standard that includes a "test board" that will be used to compare one machine to another (we have been refering to it as an IPC board). The board has components spaced from a smaller to larger pattern and at
Electronics Forum | Thu Feb 14 09:07:43 EST 2002 | PeteC
Looking at low cost reliable Mother-Daughter board interfaces. Looking at having the Mom w/ a routed out slot, like 1.7mm wide with solder lands on the bottom side then plugging in Daughter thru Mom's slot w/ the Daughter having board edge contacts t
Electronics Forum | Tue May 21 17:25:28 EDT 2002 | Carol Stirling
Hi Dave F, Thanks for the reply, the question was Customer driven. Could you clarify your recommendations for heat sealed moisture barrier bags please - does this include Nitrogen vac pack? Our production runs are small, so there is an investigat
Electronics Forum | Fri Jun 21 12:49:58 EDT 2002 | surinder
Hi Russ, Thanks for your input.My board has SMT Chip components, SOT23,SOIC's & 2QFP (25MIL PITCH). Also,taking consideration that the board is well design for Wave.This board has been designed end of last year. We have latest model of Electrovert ma
