Electronics Forum | Tue Jul 11 12:59:26 EDT 2006 | mattkehoe@sipad.com
We are trying to apply solder to boards with 80 microinches of electro plated hard gold. No components involved, just print 63/37 paste and reflow. The results are very poor on some boards, not so bad on others? Pictures at http://www.sipad.net/thick
Electronics Forum | Wed Jul 12 11:26:12 EDT 2006 | flipit
Hi, I believe you have classic gold imbrittlement here. With 80 microinches of gold you are way over the limit. You can try to reflow longer time and at a higher temperature. The gold does not melt into the solder joint. The gold dissolves into
Electronics Forum | Tue Jul 11 14:09:54 EDT 2006 | Chunks
Not reflowing completely. Slower = hotter. Try a slower conveyor speed.
Electronics Forum | Wed Jul 12 11:46:00 EDT 2006 | flipit
Hi, One other note. You don't want gold to be more than 1% to 2% of the the solder joint. Above this percentage you will have embrittlemant issues. Lots of information on gold embrittlement on this site and on the Internet. I estimate your produ
Electronics Forum | Tue Jul 11 20:13:05 EDT 2006 | davef
We agree with Chunks. You need to turn-up the heat [slow the conveyor] because you have significantly changed the melting point of the solder alloy by adding so much gold. Relative to ENIG you should expect: * Similarly smooth surface, possibly a l
Electronics Forum | Tue Oct 24 09:35:56 EDT 2000 | Wister
Our important customer demanded us to use 12mil thick stencil,it is too difficult to release solder paste from stencil.it is not helpful even I ask stencil supplier polished the openings.The flux content is 10%. I want to ask if the polyurethane sque
Electronics Forum | Wed Nov 01 12:19:42 EST 2000 | Fraser
Steve, someone somewhere is feeding you a line!! if you increase the draft angle from || to / \ on your laser cut stencil you increase the surface area of the side wall and hence increase the likelyhood of the paste sticking in the aperture. Whats m
Electronics Forum | Fri Oct 27 11:34:30 EDT 2000 | Steve A
Wister, I agree with the other comments as far as challenging the customer, and minding proper height/width or better yet area aspect ratios. Let's assume you need to go with a .012" stencil for arguments sake. Talk to your stencil supplier about h
Electronics Forum | Wed Nov 01 11:31:39 EST 2000 | Fraser
Is it possible you could simply over print to achieve the same paste volume? Supply me the numbers and I will do the calculation for you. Cheers
Electronics Forum | Mon Dec 20 12:50:27 EST 1999 | Wolfgang Busko
Hi Pascal, 0,65mm pitch normally isn�t much of a problem. With 90�m CU I don�t have any experience but would like to know what deviation from nominal value for the pads you get with different PCB-deliveries. In short, for the standard Cu=35�m we se
