Electronics Forum | Wed May 17 13:48:37 EDT 2006 | dwelch123
I'm having trouble printing leads on a fine pitch part. The lead is only .008". I'm using a DEK 265 with metal squeegee and using WS200 multicore solder paste.The stencil is laser cut and polished. I've experimented with different pressures and diffe
Electronics Forum | Thu Jun 16 09:13:46 EDT 2005 | russ
We use a 5 mil for 16mil pitch QFPs, Make sure that the stencil has been polished. Type 3 paste. We have used lead free no-clean, lead no-clean, and water soluble lead pastes for these packages. We set the printer for a slow stroke .7 in/min. wi
Electronics Forum | Thu Jun 16 22:14:51 EDT 2005 | davef
16 thou pitch parts: Use a 5 thou laser cut electropolished stencil with 0.008"x0.045" apertures and type 3 solder paste. Bridges Connecting or Partially Connecting Adjacent Leads or Lands * Excessive solder paste * Excessive component placement pre
Electronics Forum | Thu May 18 10:20:55 EDT 2006 | slthomas
Russ asks good questions and I think Chunks pretty much nailed it. Aspect ratio (aperture width/stencil thickness) s/b 1.2 minimum (I like 1.5 if I can get it). If your aperture width = lead width (.008"), yours is 1. Tough to get consistent paste r
Electronics Forum | Mon Sep 25 17:06:36 EDT 2000 | JAX
LarryK, You might want to talk with: Fancort Industries, Booth #2630 31 Fairfield Place West Caldwell, NJ 07006 973-575-0610 www.fancort.com MLCS-1 Manual Lead Conditioning System. It is a bench top, hand operated machine to correct deformed lea
Electronics Forum | Thu Sep 07 03:47:07 EDT 2006 | vicknesh28
I have been getting non wets on fine pitch QFP packages on random leads during reflow process. I noticed that every time there is some flux residue left between the non-wet lead and the solder pad. No residue was not observed on the rest of the good
Electronics Forum | Mon Dec 10 13:26:40 EST 2012 | dyoungquist
We are using our selective solder machine to solder a backplane with sixteen (16) 4x48 pin 0.080" connectors. Our first pass yield is about 85% meaning that 85% of the connectors come out with no bridges. Not quite as fine pitch as your connector a
Electronics Forum | Thu Sep 07 10:45:46 EDT 2006 | vicknesh28
Yes solder is reflowing on the pad but doesnt wick up the lead. Solder paste is sufficient. It just forms a saddle like appearance beneath the failing lead. The failed lead doesnt get reflowed at all. What puzzles me is how can hundreds of leads wet
Electronics Forum | Thu Sep 07 08:44:17 EDT 2006 | vicknesh28
Did check the coplanarity of the failed lead and found it to be as good as the wetting leads.
Electronics Forum | Wed Sep 18 20:55:33 EDT 2002 | scottefiske
I'm with you dave...please provide specifics as to defect condition... Are you getting good wetting to both land and lead? Is there any repeatability to lead/location/device? Do you have paste inspection capabilites to verify deposition? Is it a Pala
