Electronics Forum | Fri Mar 23 21:36:02 EST 2001 | CAL
If you do not have any luck finding a west coast lab, but need services I am sure we can help. The only problem is we are on the east coast. Many moons ago empf was on the west coast (China Lake) but moved eastward. We are in Philadelphia, PA. (ski
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 | Thu Jun 03 18:00:33 EDT 1999 | John Thorup
.020" pitch spacing. Which have yielded my process excelent results. | | My main stencil supplier is I-Source in Irvine, CA and has pretty much standardized on 100% lazer cut stencils for competetive pricing. | | Hope this helps. | | | | Deon Nunga
Electronics Forum | Fri May 21 15:50:41 EDT 1999 | John Thorup
We are running a number of boards with 8-10 25 mil PQFPs on board. Our process is mature with at least 3 years experiance and statistically few opens on the QFPs. Our beloved purchasing department has chased the almighty $ and changed FAB vendors
Electronics Forum | Thu Mar 05 23:33:53 EST 1998 | Ron Costa
| | Hello everyone! | | Does any know anything about bare board size variations? | | Is there a spec. or tolerance? | | I'm running small lots of boards and during the screen printing process | | I find that I cannot paste each board perfectly.I've t
Electronics Forum | Wed Jun 04 14:33:28 EDT 2003 | joeherz
CAL, Thanks for the input. When I said chemistry I was refering to soldering chemistry and not cleaning. I believe this machine has the capability to incorporate a saponifier but would prefer not to run in this manner. Running a closed loop DI re
Electronics Forum | Fri May 21 20:38:40 EDT 2004 | Grant Petty
Hi, This would be a very exciting idea. Nitrogen is an inert gas, so this is why it's used, however Hydrogen mixed with oxygen in normal air is highly explosive, so it would be one of the worst gasses to use in a reflow oven I would think. Remember
Electronics Forum | Wed Apr 27 02:22:08 EDT 2005 | grantp
Hi, There are a number of things you can try. You are already using 1:1 hole to pad ratio, and that's good as you need the size. I would try an electroform stencil as that will have a smooth side of the aperture and help paste release. Don't use c
Electronics Forum | Thu Dec 08 08:22:58 EST 2005 | grantp
Hi, How fine pitch are you going? What kind of stencil printer are you using? We had a manual stencil printer and needed to print 1-mm pitch BGA and needed to go to laster cut and electro polish at 4 thou to get good paste release. We also went 1:1
Electronics Forum | Thu Apr 12 09:50:51 EDT 2007 | pjc
There have been many designs of apertures for 0402, round, home plate, inverted home plate and various reduction amounts for square or rectangular apertures. What works best for a given application depends on PCB design, solder land finish, stencil t
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