Electronics Forum | Wed Dec 10 14:37:47 EST 1997 | Frank Murch
There is a direct relationship between adhesive strength and surface area. If you graph this it will be linear. The amount of the adhesive should be about 2/3 the gap between the pads. Pad designs change all over so a true and tried rule does not ex
Electronics Forum | Wed May 20 09:52:50 EDT 2009 | dwelch123
Use a push/pull tester. I use an OBA inst. works Ltd. tester. Just because mask comes off with bonder doesn't mean bonder is strong or cured right. Mask can be weak in between pads do to area size. Do it right and you'll know for sure. To many people
Electronics Forum | Fri Sep 02 06:47:17 EDT 2005 | dougs
Is there a standard that we should aim for in respect to the strenght of the solder on SMT leads? We have a customer who are testing our product by pulling leads off of pads then returning them.
Electronics Forum | Fri Sep 02 09:02:10 EDT 2005 | dougs
you tell me, the customer has started to pull at some of the leads of some IC's with tweezers while de-bugging boards that had failed in the field, he was able to pull some of the leads away from the solder joints, we feel he may be over-doing it a
Electronics Forum | Wed Dec 10 11:11:04 EST 1997 | Rich Scheleski
Is there a spec for the adhesives used to hold down parts before wave soldering. What size dots are recommended and what is the maximum shear force(1LB?) tested for to ensure good adhesion. Your help is appreciated Rich Scheleski
Electronics Forum | Sun Jan 11 12:03:51 EST 1998 | Bob Willis
As a basic guide the minimum spec you should look for is 500g you should achieve a force on most chip parts of 800-1000g. Parts are lost on wave soldering due to no material, poor curing, poor surface adhesion and poor handling. Its not the wave sold
Electronics Forum | Wed Mar 30 16:07:24 EST 2005 | Dreamsniper
If there's no shear strength standard for solder joint, how will I define my pad width and length then. I have a 8.5 mils width and my component lead width is 8.66 mils based on manufacturer's minimum width specification. How will I identify that it
Electronics Forum | Wed Oct 06 03:18:01 EDT 2004 | Joseph
Dear all, Recently our customer complaint that some components being came off from the pcba after dropping test.But the curious is, the leads show visible solder fillet covering more than 75% of termination area on pad, which is acceptable as per IP
Electronics Forum | Wed Mar 30 16:46:03 EST 2005 | chunks
There is no spec because solder is designed to provide an electrical connection not a mechanical connection to hold the part on. If it where mechanical we�d be welding our parts on. Your pad width and length are derived from your component manufact
Electronics Forum | Thu Dec 09 07:46:42 EST 2004 | davef
We did this for BGA pads, but have not thought about other types. So, this may or may not apply for those. Pad defined by:||Advantages||Disadvantages Non-solder mask||No point-of-stress concentration at edge mask and solder ball||Smaller pads have
