Electronics Forum | Tue Mar 11 10:19:00 EST 2003 | yngwie
We ran doublesided SMT thru Glue and Wave process before and but faced a lot of skip solder. Then the customer told us that they have similar problem when they ran the board so what they did was they print the paste-dispense the glue- place the comp
Electronics Forum | Thu Mar 13 15:13:17 EST 2003 | ruggi
That's a good idea...and to add on to it, you could wash after the wave, too--it really doesn't matter. A question about this though--unless your Customer specifically requires "clean", no-clean flux whether it's ugly or not, is permitted by IPC,
Electronics Forum | Tue Jul 15 22:50:12 EDT 2003 | iman
We have an internal engineering study on blowhole solder joints and had helped reduce the problem to pinholes symtoms. The pinhole occurs in solder joint of a Land-Grid-Array (LGA) side-wall (external perimeter of package) fillets. Our customer is a
Electronics Forum | Sat Nov 08 09:42:22 EST 2003 | ethercom
Hi: I have seen this problem before. It is caused by improper curing of solder mask by the fab manufacturer. When you run the board thru' wave solder, and then wash the board, you see the problem of white residue. However, when you apply heat, you c
Electronics Forum | Mon Jun 20 10:59:18 EDT 2005 | Jason Fullerton
Extra cooling is better (Alpha recommends -3 to -7 degC/sec) for cosmetics. Less chance of s o called 'cooling lines' that look similar to 'cold' tin-lead joints. (Seems a bit steep to me - I worry about the risk of cracking ceramic caps.) Might be
Electronics Forum | Tue Jun 28 12:12:17 EDT 2005 | Paul
I'm with DaveF on this one. I think you'll be trying solve this one for a long time. Alloy42 just doesn't like to be soldered. What exactly is the issue? Lack of a toe fillets at on the cropped lead? There is no spec for a toe fillet other than to
Electronics Forum | Mon Feb 13 10:33:57 EST 2006 | fredericksr
Hello, I am automating a process on our floor from wire solder hand application to dispensed paste and reflow. The process involves "lidding" a shielding lid around our assemblies for microwave quieting. The result is non-hermetic. For cosmet
Electronics Forum | Fri Feb 24 13:39:35 EST 2006 | Chunks
I agree with Jerry. A 7 mil stencil should work just fine for 25 mil pitch parts and 0.050 pitch BGA's. I too go 6 mil, but whith proper screen printing, you can 7 mil. You can always do 5 ot 10% reductions if needed. Use the homeplate design on
Electronics Forum | Sun Feb 26 17:40:35 EST 2006 | GS
Hi, just my comment, theoretically No Clean means no Ion Contaminants from Flux, but it some some case ion contamination (Cl-Br-F) could come out from raw PCBs, from Components, from fingerprints, etc. To incorporate a ROSE step in the pro
Electronics Forum | Mon Mar 27 09:58:19 EST 2006 | samir
When you say "unacceptable" do you mean cosmetically unacceptable? I've always put as much flux (no clean, of course) on the board until the ICT guys start yelling at me. That's how I roll... Lots of factors with no-clean flux residues...board mas
