Electronics Forum | Mon Aug 27 12:51:32 EDT 2012 | cobham1
I have run 0.031 boards. One of the things you may want to look at is the speed of the oven. With 14 zones you may be going to slow with the board which could be the reason your boards are starting to bow. You might also think about adding stiffners
Electronics Forum | Mon Aug 27 11:11:16 EDT 2012 | rway
We have 1/2 dozens 0.031 pcbs that bow after going through the oven. We are looking for a solution to this problem to prevent bowing of the pcbs. As a result of the bowing, the pcbs, on occasion get caught in the oven, and more often have transfer
Electronics Forum | Tue Aug 28 08:28:30 EDT 2012 | rgduval
We agree with all of the previous comments, and would add the following: Warpage is generally caused by excess moisture in the raw boards. Have you tried baking the boards prior to assembly? We had this issue on a simple 4-layer board, and found t
Electronics Forum | Mon Aug 27 12:31:04 EDT 2012 | rway
Its no my turn to give some advise. My first > question would be can you put the boards into a > carrier of some sort. There are many wonderful > companies that make carriers that are ment for > running down a smt line. This can be expensive > u
Electronics Forum | Mon Aug 27 11:51:47 EDT 2012 | cobham1
Its no my turn to give some advise. My first question would be can you put the boards into a carrier of some sort. There are many wonderful companies that make carriers that are ment for running down a smt line. This can be expensive unless you order
Electronics Forum | Thu May 18 20:47:14 EDT 2000 | Dave F
Ed: It might be possible, never tried tho, but if an engineer wandered in, talking about it ... Printing: Makes me pretty nervous, because punched boards are not planar, don�t stay planar, and are inconsistently not planar. If I could work-out th
Electronics Forum | Mon Oct 29 18:21:43 EST 2001 | slthomas
We recently have received a lot of warped (bowed and/or twisted behond IPC 600 specs.) bare boards (some our fabricator's fault, some ours by design) and I can't help but figure that long term reliability will suffer when building product with them.
Electronics Forum | Fri May 19 10:39:19 EDT 2000 | Boca
Ed, I workded with punch and replace fabs yeeeeears ago, major pain! Dave's right, planarity is the biggest problem, then inconsistent retention in the panel, then ANY retention in the panel. If you can get paste on them, you may be able to place
Electronics Forum | Fri May 19 10:41:06 EDT 2000 | Boca
Ed, I workded with punch and replace fabs yeeeeears ago, major pain! Dave's right, planarity is the biggest problem, then inconsistent retention in the panel, then ANY retention in the panel. If you can get paste on them, you may be able to place
Electronics Forum | Thu Dec 12 15:34:59 EST 2002 | msimkin
Has anyone had any expereince with FR4 boards under the std 0.5% warpage for Bow & twist with CSP & uBGA devices on them that have caused failures. Are there any revised percentages for boards loaded with these devices that anyone knows of, istead of
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