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 | Thu Nov 29 15:08:56 EST 2007 | jaimebc
Shy, You mentioned that you are using "dog bone" apertures for your chip components? It doesn't make sense to me. I thought that the "dog bone" was used for fine pitch devices, to keep the solder away from the center and avoid bridging. It doesn't
Electronics Forum | Wed Nov 28 16:08:38 EST 2007 | jmelson
I've been using Xilinx TQFP's in the 44 and 144 lead sizes with no trouble. I don't even bake them before reflow and have never had any problem. The Xilinx parts are certainly NOT sensitive, I could not break one with my bare hands if I tried (I ha
Electronics Forum | Thu Nov 29 16:00:03 EST 2007 | jmelson
Desoldering often applies a LOT more heat and thermal stress to the part, and maybe mechanical forces while everything is hot, to get the part free of the board. So, a lot of damage might be done there, making post-mortem harder. Without the leads,
Electronics Forum | Fri Dec 07 15:12:56 EST 2007 | teodor
Hello , I would like to collect your valued opinions what is better for beggining . Samsung CP-45NEO Juki 2060 Light Feeder Positions (8 mm) 104 80 PCB Size (min - max) 50x30-460x400 mm 50x30-410x360 m
Electronics Forum | Mon Dec 17 06:48:05 EST 2007 | andy1975
Hi all Just found this forum and spent the last three hours reading your posts! I'm considering investing in a budget smt production line, and this is why: The company I work for manufacture very very small batches of boards, four a month for one p
Electronics Forum | Tue Jan 15 15:53:14 EST 2008 | jmelson
I only build my own products, so it has to meet my needs for QA only. I am doing some 20 mil lead pitch (0.5mm) and will soon be doing a 0.4 mm pitch part. I have more magnification on my microscopes (40X) but almost never need to go that high. If
Electronics Forum | Tue Feb 12 17:57:42 EST 2008 | chef
I must ask the silly question- are you sure you deposited the correct amount of paste? Depending on aperature design-the voiding could come from a stencil that has its holes partially built up with old paste. If paste volume is guaranteed, then what
Electronics Forum | Thu Apr 10 08:23:27 EDT 2008 | scottp
If I read you right the issue is mostly with components from one supplier. I'd suggest looking at the components under a microscope. Also, if you have some old pre-tombstoning parts from this same vendor take close-ups of both and compare them side
winsouce.jpg)
.gif)
