Electronics Forum | Wed Dec 15 08:15:10 EST 2004 | pjc
UP78 is an old product. Data sheets are no longer posted on the web site. OM-5100 is the replacement. Try calling tech support and they should e-mail you the UP78 data sheet that will show the profile curve. Jersey City, NJ Tel: 201-434-6778 http://
Electronics Forum | Sun Feb 27 13:42:44 EST 2005 | pmdeuel
So true, We had paste flux supplied to us from Alpha metals. It was the same as used in the solder paste. The major problem we noted was the in ability to control the ratio of paste to flux resulting in lots of voids. When we mixed enough to get the
Electronics Forum | Mon Feb 28 08:06:49 EST 2005 | davef
You'll be able to tell pretty soon if this will work. * Our bet is the epoxy will corrode the silver. * Another concern is that you're not fusing the silver to the copper. Why not ask the imm silver suppliers: * Alpha Level Silver [ http://www.al
Electronics Forum | Fri Mar 04 10:04:14 EST 2005 | jbrower
We use Alpha UP-78 (Older paste formula) and it works well for what we do. We standardized our stencils at 5mil with a 10% reduction on IC apetures and a home plate design on passive components. Additionally we use laser cut electro-polished stenci
Electronics Forum | Wed Apr 27 09:15:30 EDT 2005 | russ
You will probably need to change paste. If I remember correctly the SMQ92J has a post reflow residue of 40%. This is one of the highest post reflow residue levels available. PIH uses a lot of paste which means a lot of flux residue. There are othe
Electronics Forum | Mon May 16 06:36:51 EDT 2005 | steve
I see what you mean. Personally I would try a bit of the paste and see what you think prior to production run. If I were you I would get another brand in there. something that offers a "slightly" longer life? I have used "out of date" solder paste ma
Electronics Forum | Fri May 20 15:13:29 EDT 2005 | lyrtech
We don't know if our solder pot is producing too droos or not. When we get it out of the solder pot, we have to add around 50 lbs of solder bars. I think it's an important quantity. I want to know your feeling about that. We use Alpha Metal Hiflo Bar
Electronics Forum | Thu Jun 16 08:31:15 EDT 2005 | jh0n!
The most part I have the most difficulty with is a 16mil QFN. We found that reducing stencil thickness to 4mil, and reducing aperatures for the IC by 20%, and setting local fiducials to the IC helped immensely. We used to get 75% or more bridged ou
Electronics Forum | Wed Jul 13 14:56:53 EDT 2005 | jdengler
I read the Cookson/Alpha paper "Optimizing stencil design for Lead-free SMT processing". I interpreted it to mean that if you had a mid chip solder ball (MCSB) problem the "radiused inverted home plate of 20/60/20 style" had the greatest impact on r
Electronics Forum | Mon Nov 14 17:09:07 EST 2005 | davef
From Alpha Metals: "The test for copper dissolution was conducted by dipping a pre-fluxed copper wire specimen into the test alloys for a specified time period. The change in diameter of the copper wire is measured and a rate of erosion is determined
