Electronics Forum | Tue Nov 27 08:21:43 EST 2007 | shy
How many mils the gap between the terminal and pad? Your practice is for technology SMT-4? What is problem with glue cure? is it due to the reflow profile? how long the glue can be keep in room temperature with humidity 40-60?
Electronics Forum | Wed Nov 28 01:28:32 EST 2007 | shy
Q1:What is the relation between component standoff and drop missing? A1:component standoff will identify either solder paste at SMT side can form the fillet at component terminal or not. Drop/missing component is totally out of the topics since i jus
Electronics Forum | Mon Nov 26 20:11:41 EST 2007 | shy
Yes, i'm agree with you davef but i'm not put the chipbonders onto pads. i'm put the chipbonders at the beneath component (center between both component terminals) which the idea is to hold the component during wave soldering which might cause the co
Electronics Forum | Tue Nov 27 20:48:31 EST 2007 | davef
Shy: You say, "I've already done some evaluation to reduce the heigh of the glue but it fails at wave solder which cause the component to be drop/missing." Based on your evaluation, questions are: * What is the relation between component standoff an
Electronics Forum | Tue Nov 27 14:56:33 EST 2007 | jaimebc
Shy, What is your current method of applying adhesive? If the terminals of the component that has adhesive are not wetting ( or not forming a solder joint I think we are talking about ) after reflow, then you must be applying too much adhesive. As
Electronics Forum | Thu Nov 29 22:38:05 EST 2007 | shy
Hi Dback, Yes, i'm open "dog bone" aperture for my chip component. this is to prevent solder ball issue. For fine pitch i'm opening square with full length and half width to prevent bridging. Btw, if "dog bone" is not for chip component, what is your
Electronics Forum | Wed Nov 28 01:07:36 EST 2007 | shy
is there any standard gap between the terminal and pad if we place the glue? SMT-4 mention as per what you understand which is using glue at SMT without solder paste and run at wave solder for the solder paste at the terminal. Glue supplier recomm
Electronics Forum | Tue Nov 27 08:13:04 EST 2007 | davef
C1: is there any gap between the pad and terminal if we place the glue? R1: Yes, there is a gap, but it is easily bridged by the amount of solder in the wave. C2: Btw, my practice to print solder pate then punch glue then PNP component and finally
Electronics Forum | Tue Nov 27 20:05:31 EST 2007 | shy
Dback, Current method is by using dispenser machine to dispense the glue at PCB. This non-wetting is randomly and not repeating to the same location. My adhesive height is 0.01" to 0.035". Is this will cause the component to had a gap between the t
Electronics Forum | Tue Nov 27 20:19:12 EST 2007 | davef
Q1: How many mils the gap between the terminal and pad? A1: It depends on properties of the glue and z-force when the component is placed by the assembler. Q2: Your practice is for technology SMT-4? A2: We don't understand SMT4. We know that very sm
