Electronics Forum | Mon Jun 18 13:29:34 EDT 2001 | nifhail
What is the recommanded profile for board which consist of 0402 & 0201 comps. to reduce the effect of tomb-stone. Slow ramp rate ? how slow is considered as slow. Soak time 60 or 120 C,at which end should I stick to? what is the best time before reac
Electronics Forum | Wed Jun 20 12:07:13 EDT 2001 | Steve
I would suggest getting a copy of IPC-SM-782A, Surface Mount Design and Land Pattern Standard, and IPC-7525 Stencil Design Guidelines. My experience is that reflow does not cause tombstoning very often. Pad and land design, paste volume, and placemen
Electronics Forum | Wed Apr 21 11:33:20 EDT 2004 | tigerlordgm
As one of our small batch processes, we place BGAs on PCB without using solder paste. We apply tacky flux to a predetermined height on a pallet, "dip" the BGA into the tacky flux to wet the solder balls to the set height, and then use a BGA rework st
Electronics Forum | Thu Aug 17 12:18:40 EDT 2017 | cyber_wolf
I do not see anything obvious that would cause a thermal mis match. Regarding reflow profiles reducing tombstoning, Unless there is something wrong with your paste or you are running smaller than 0402's, I have NEVER seen a reflow profile reduce tom
Electronics Forum | Wed Nov 01 14:42:17 EST 2000 | MRMAINT
We had some similar issues on one of our products.The oven profile is critical. We found that with a gradual soak ramp up it took care of about 80% of the tombstoning.The other thing that we found was pad design issues. Take a look at the sept. issu
Electronics Forum | Sun Mar 20 12:58:23 EDT 2011 | sellenzz
We have a Nitrogen Silo. Your going to want to be careful if you decide to use nitrogen, not only are the levels unstable most of the time but it can also cause your components to tombstone like crazy, especially if you run a lot of LED's. We run 24/
Electronics Forum | Wed Jun 11 16:30:33 EDT 2003 | T.Vick
You have received some great feedback so far. I would like to summarize and add a few points regarding maintenance. You should start (as recommended already) by verifying your component library data. Using the default values from the master library i
Electronics Forum | Thu Aug 27 11:18:05 EDT 2015 | dyoungquist
From your description I am assuming you are doing double sided reflow and parts are dropping off the bottom side when the board is run through the reflow oven the second time. A few ideas to try: 1) Are the parts that are dropping off heavier parts
Electronics Forum | Thu Nov 03 10:43:04 EST 2005 | russ
Good Luck! Good profile and correct pad design will make for an easy 0402 and 0201 without tombstone process.
Electronics Forum | Fri Mar 07 08:47:45 EST 2003 | msivigny
Hello Peter, In reflow, running a profile and collecting thermal data does not necessarily make it easy to calculate and determine machine capability. On the contrary to your desires of simplifying the process, determining machine capability on an ov
winsouce.jpg)