Electronics Forum | Mon Sep 09 21:02:30 EDT 2002 | davef
Bernard Interesting point. Please help us better understand: * Why do 'VIA hole, PTH hole sizes may need to be changed', aside from the obvious with hole-to-lead clearance? * What should the designer 're-evalaute the board before changing'? * What
Electronics Forum | Wed Oct 23 12:06:09 EDT 2002 | russ
It sounds like you already know the answer! How much does it cost you to solder P.T.H. by hand (number of pins/per hour, / cost of assembler) vs. wave preparation and time of loading/masking etc... Cost of rework from each process? Only you can mak
Electronics Forum | Thu Oct 24 01:10:54 EDT 2002 | pizz
thank ur kind help. the above two processes,which is more reliably,other words,robust? I am in a dilemma. some suggest that 50 pins is the critical point,once exceed the quantity,the hand soldering is not practical. I prefer to two sides reflow.but
Electronics Forum | Mon Oct 21 13:12:38 EDT 2002 | pr
Try a "cross" design across the problem apertures. So you wind up with 4 smaller deposits on the PCB (instead of 1 big one) but should be enough to hold the component. It worked for us and was much easier on the blades (they kept catching on the far
Electronics Forum | Wed Oct 30 09:28:50 EST 2002 | gregp
How about your designator actually contains size info in a code. For example, SO14-237-050-090. That is "package type" - "width" (over leads) - "lead pitch" - "thickness". The problem with this is a great deal of thought has to be put in before comm
Electronics Forum | Thu Nov 07 12:35:38 EST 2002 | slthomas
Sounds like you're talking about the "heel" of the lead not being soldered, in other words, no heel fillet, which IS necessary. That problem, for us, was attributed primarily to poor layout (insufficient length of pad extension to provide room for
Electronics Forum | Tue Dec 10 14:10:38 EST 2002 | Randy Villeneuve
Steve, I wave solder most if not all our boards with selective wave pallets. I did not catch if the solder balls were on top of the board or on the bottom but that will make a difference on what to do to get rid of them. Pallets are good and bad. On
Electronics Forum | Tue Dec 17 08:55:52 EST 2002 | Randy Villeneuve
Grant, The board maybe the problem but how is your oven working? Is it a convection oven and how many zones (top and bottom)? What does your profile look like? If you are unsure and if you only have one oven, send your board to Soltec or Electrovert
Electronics Forum | Thu May 29 12:53:36 EDT 2003 | designchain
Managing items and BOMs, even for a small company, should not be done on spreadsheets - they're single user, prone to error, and hard to manage. There are relatively low-cost, very functional systems on the market that enable management and revision
Electronics Forum | Sun Dec 15 22:31:43 EST 2002 | craigj
Has anyone heard of vias cracking (barrel from pad) when being wave soldered. Was told this was a big problem by contract pcb designer, he always tent vias because of this. The reason was that the solder filling the vias caused stressing and then sep
