Electronics Forum | Thu Aug 12 22:38:44 EDT 1999 | Dave F
| Hello | | Having a problem with bridging on 20mil pitch qfp, only on the lead groups where squeegee goes over width of apertures. Using MPM sp-200 semi-auto, chem-etch stencil, 9-10mil width opening | 100 durometer blade. Getting "tails" on deposi
Electronics Forum | Fri Aug 13 12:52:17 EDT 1999 | Steve Schrader
| Hello | | Having a problem with bridging on 20mil pitch qfp, only on the lead groups where squeegee goes over width of apertures. Using MPM sp-200 semi-auto, chem-etch stencil, 9-10mil width opening | 100 durometer blade. Getting "tails" on deposi
Electronics Forum | Fri Aug 13 13:50:53 EDT 1999 | Brian Wycoff
| | | | | | Hello | | | | | | | | | | | | Having a problem with bridging on 20mil pitch qfp, only on the lead groups where squeegee goes over width of apertures. Using MPM sp-200 semi-auto, chem-etch stencil, 9-10mil width opening | | | | | | 100 du
Electronics Forum | Thu Jul 15 18:07:04 EDT 2004 | dwanzek
This has been a tough one to date. Any ideas will help. Problem definition � random QFP144 part not soldering all leads. Percentage fallout is about 1-5% of boards. Usually leads, one or more, on trailing side to the direction of travel does not wet
Electronics Forum | Fri Aug 13 13:47:52 EDT 1999 | Brian Wycoff
| | | | | Hello | | | | | | | | | | Having a problem with bridging on 20mil pitch qfp, only on the lead groups where squeegee goes over width of apertures. Using MPM sp-200 semi-auto, chem-etch stencil, 9-10mil width opening | | | | | 100 durometer
Electronics Forum | Sat Sep 22 01:30:31 EDT 2007 | mika
I am sorry my friend, but I can't recall that specific error number. But it would help if you explain a little bit more about your problem. Remember that an error code Do Not necessary points to a direct root-cause of a problem. First of all we nee
Electronics Forum | Tue Feb 04 17:24:07 EST 2003 | jonfox
we have some pretty tight 0402 placements and our best fix was to reduce the pad (vertically speaking) from .030x.022 to .020x.022. Fewer tombstones and the paste flows out to the edge of the pads nicely. Only difference is that we have a 6mil sten
Electronics Forum | Thu Feb 08 15:47:08 EST 2007 | realchunks
We use 1 to 1 aperture on a 6 mil stencil, no problems. Do not over print unless your board resist allows you too.
Electronics Forum | Fri Oct 22 06:19:42 EDT 1999 | TNT
Ron, if I am reading this correctly the 20mil parts are not having problems on a 6mil stencil. If you increase the entire thickness of the stencil to 8mils, there should not be any issues with the 20mil components. The supports you are using could p
Electronics Forum | Thu Oct 21 14:02:32 EDT 1999 | Ron Costa
We are a contract manufacturer currently building a job with IBM CBGA-255 devices and 20mil QFP's that are close to each other. We use a 6 mil laser cut and electro polished stencil with one to one apertures on the BGA's. The customer is experiencing