Thanks for the quick reply Jorge. Glad to know that you guys have done this before. Continuiing on the topic a little more, our case here is that of double sided reflow - with the components that have to be reflowed on the bottom and those to be cured on the top side as the board goes into the forced convection oven. The chief concerns here with some of the process engineers are one of chemical interactions between the glue and the solder paste. Whether there might be any outgassing from either one of the materials that might affect the cure/solderability and the future performance of the other material. I am kinda wondering how to set-up and study this phenomena (if at all it exists!). Any ideas floating around?? Regards, Murugan --- Jorge Engenharia <[log in to unmask]> wrote: > Murugan; > > I did this in the past to avoid 0603 tombstoning > during reflow until new > land size was modified in the board. It worked well > !!! > First we applied solder paste using screen printer > and then we applied > glue using a syringe dispense equipment ( Panasonic > ) using a double dot > pattern nozzle, this process requires continuos > monitoring due some times > you get the nozzle dirt with solder paste. We did > this in 1994 when a new > board design was made using 0603 and nobody realize > that tombstone could > happen, that time 0603 were a new component for us > and until we get the > problem fixed by changing land pattern design and > solder paste ( we did a > small DOE study ), we had to apply adhesive to avoid > tombstone and keep > production running ( 10000 boards per day !!! ) > The adhesive used were Loctite 3605 ( I am not > sure about the number, but > it were red and came in 20 ml syringe package ) and > the reflow profile were > the same that I used for solder paste. > I believe this process is used also for double > sided reflow with heavy > components on both sides. > > Thanks > Jorge Dourado de Santana > Maintenance / Process Engr > Microtec - Brazil > > > > -----Original Message----- > > From: Murugan Vasudevan [SMTP:[log in to unmask]] > > Sent: 15 de Fevereiro de 2000 12:24 > > To: [log in to unmask] > > Subject: [TN] Cure and Reflow > > > > Hi Technetters, > > > > Just wondering if anyone of you have done > simultaneous > > cure of SMD adhesives and reflow of solder paste > in > > the same pass. Any information/leads on any > previous > > experiences with this process will be very > helpful. > > > > Thanks, > > > > Murugan. > > __________________________________________________ > > Do You Yahoo!? > > Talk to your friends online with Yahoo! Messenger. > > http://im.yahoo.com > > > > > ############################################################## > > TechNet Mail List provided as a free service by > IPC using LISTSERV 1.8c > > > ############################################################## > > To subscribe/unsubscribe, send a message to > [log in to unmask] with > > following text in > > the body: > > To subscribe: SUBSCRIBE TECHNET <your full name> > > To unsubscribe: SIGNOFF TECHNET > > > ############################################################## > > Please visit IPC web site > (http://www.ipc.org/html/forum.htm) for > > additional > > information. > > If you need assistance - contact Gayatri > Sardeshpande at [log in to unmask] or > > 847-509-9700 ext.5365 > > > ############################################################## > __________________________________________________ Do You Yahoo!? Talk to your friends online with Yahoo! Messenger. http://im.yahoo.com ############################################################## TechNet Mail List provided as a free service by IPC using LISTSERV 1.8c ############################################################## To subscribe/unsubscribe, send a message to [log in to unmask] with following text in the body: To subscribe: SUBSCRIBE TECHNET <your full name> To unsubscribe: SIGNOFF TECHNET ############################################################## Please visit IPC web site (http://www.ipc.org/html/forum.htm) for additional information. If you need assistance - contact Gayatri Sardeshpande at [log in to unmask] or 847-509-9700 ext.5365 ##############################################################