Electronics Forum | Mon Mar 07 06:44:39 EST 2022 | SMTA-64386201
We previously labelled PCBs after assembly but before AOI. Now we need to trace panels during assembly as well, so have the need to apply labels before the assembly process starts. Our stencils are thus not stepped to accommodate labels. I suppose t
Electronics Forum | Thu May 10 16:17:59 EDT 2001 | davef
I am unaware of any industry standard for specifying apertures for SM stencils. I am aware of IPC-7525, Stencil Design Guidelines. You can obtain it from IPC [http://www.ipc.org]. Further, it seems like there is an article on stencil design ever
Electronics Forum | Fri Dec 17 08:05:00 EST 2004 | davef
Your solder paste is talking to you, follow its message. Listen to the paste. Be at one with the paste. If you insist on ignoring the message of the paste, add more paste, if you just need to complete the last board or so, but you really should ju
Electronics Forum | Tue Feb 22 01:38:42 EST 2005 | JSS
We r using QFPs of 0.5mm pitch and r not getting any soldering prob at the end.But some new customer insists upon the thickness check of the solder paste after printing. At present we don't hv thickness checking system.We r controlling the amount of
Electronics Forum | Mon Apr 12 15:52:12 EDT 2004 | wgaffubar
I am using Indium 92J type 4 solder paste due to a BGA site with .008" pads and stencil opening of .009" square and .005" stencil thickness. When I try the type 3 we get insuffecient print. The aspect ratio tells me that I should be using a type 4. T
Electronics Forum | Tue Apr 13 14:14:59 EDT 2004 | russ
I have actually printed this same condition with type 3 paste Alpha WS709. I posted this for discussion and cannot remember what I called it. We did need to clean the stencil after every three prints. I did not check volume on these locations but
Electronics Forum | Fri Apr 23 07:50:50 EDT 2004 | smtpro
We have switched over form Indium's nc-smq92 to nc-smq92j and are experiencing a ton of solder balls. Even if the print is dead on we still seem to be getting them. We never seemed to have this problem with old paste unless the print was way off. Is
Electronics Forum | Wed Jun 01 07:34:19 EDT 2005 | davef
It's unusual to use a horseshoe shaped pad for a 0805. Commonly when people want to reduce the paste volume to reduce solder balling, they print a "home plate" aperature. We print paste 1:1 with the pad. �IPC-7351 LP Wizard� is the library mainten
Electronics Forum | Tue Jan 07 23:38:08 EST 2014 | m_imtiaz
want to know the tolerance the paste height in the solder paste printing. for example if stencil thickness is 7 mil, what will the acceptance level of paste height ( upper and lower) kindly share if any guidelines or formula for the same
Electronics Forum | Mon Jun 22 16:33:59 EDT 2020 | davef
Measuring solder static paste viscosity is fairly easy to do. IPC TM-650 .4.34, Solder Paste Viscosity lists the method and equipment. Just don't tell your customer that it is meaningless because the solder paste is printed in shear, not statically
