Hi All Thanks for your Reponses I will try all your suggestions in next lot and post the results , as I had only four board that I have already used with bad results. Regards Pankaj > -----Original Message----- > From: [log in to unmask] [SMTP:[log in to unmask]] > Sent: Monday, August 16, 2004 8:46 PM > To: [log in to unmask]; [log in to unmask] > Subject: Re: [TN] Vertical fill up of 3.2mm thick PCB. > > Hi Pankaj! > > I have a board like that here that we build, and at first it gave me the > same problems you face. > > This might sound out of the ordinary, but you do what you have to do when > you are faced with a board that is unusually thick and has heavy copper > planes in it. I run the assembly twice through my wave machine. Once with > the wave pumps off to pre-heat it, then once again with the pumps on. You > could accomplish the same thing by pre-heating the board in a oven, but I > don't have a oven close by my wave machine, so I use the wave pre-heaters > instead. > > I also flux the topside of the board manually to help aid heat transfer a > little, and it seems to improve capillary action too. I also use both the > rotary and laminar wave pumps. > > I have a Electrovert Electra machine with a Optiflux-1 spray fluxer. The > machine has three bottomside convection pre-heaters. I run my beltspeed at > 3.5 feet per minute, and my pre-heaters are set at 270 F., 280 F., and 300 > F. going from the entrance to the solderpot. I use a Alpha 615-25 RMA > flux. I leave the fluxer on for both passes through the machine. > > I use a fixture for the board that has solder dams around all four sides, > so I can run the board quite a bit deeper in the wave than normal. > > As far as rework on the board I use a system from Zephrytronics ( > <http://www.zeph.com/>) called a ZT-6 Hot Air Fountain. I was turned on to > this system from a Technetter named Steve Sauer. I couldn't rework > anything on this board without damaging pads, barrels, or the PCB itself > until I got the ZT-6. > > I put some pictures up on my web page a while back of me pulling a 96-pin > connector out of that board. Look at: > > <http://www.stevezeva.homestead.com/files/ZT6.jpg> > <http://www.stevezeva.homestead.com/files/TakingTemperature.jpg> > <http://www.stevezeva.homestead.com/files/JustAbout.jpg> > <http://www.stevezeva.homestead.com/files/ItsOut.jpg> > > There's a picture of the unit, me monitoring the temperature with a > hand-held, non-contact, I/R Thermometer, me getting ready to pull the > connector out, and then me finally pulling the connector out with a pair > of tweezers...couldn't be easier! > > -Steve Gregory- > > << File: JustAbout.jpg >> << File: TakingTemperature.jpg >> << File: > ZT6.jpg >> << File: ItsOut.jpg >> > > > Dear Tecnetters " Hi " > > we have a PCB of 12 layers with thickness of 3.2mm. > > Problems we are facing are > > 1.Solder doesn't come top side and as the thickness is more than pre > established components lead lengths ,like DIP's IC,connectors pins > , it is > mandatory for us that a fully wetted solder is visible from primary > side. > > 2.Many of the components are on the ground plane , so if any rework > is > required we could not do so by soldering iron ( we tried weller 150 > watts > iron with temp. 450 deg. C , but we could not remove an electrolytic > cap.) > > 3.What IPC tells about the power connector lead protrusion and the > top side > solder fill up for the same. As the IPC 610B states in components > installation 3.5.3.1/note: that lead protrusion may not be visible > in more > than 2.3mm thick boards.How we interrelate it with soldering > 4.1/vertical > fill of soldering 75 % in this case. > > 4.We are using AC by pass connector "PICH47F400A1" with recommended > PCB > hole dia 2.1mm for lead dia 1.6mm , Is it enough for 3.2mm thick PCB > too. > > > Any body have the soldering experience of 3.2mm thickness PCB. what > parameters ( wave height/ pre heater temp ) of wave soldering M/c > matter in > this case .Is chip wave is useful , Pls. share your exp. it will be > highly > appreciated. > > Thanks > > BR > Pankaj Karnwal > Jr. Engineer QA > > Barco Electronics System (P) Ltd. > Plot no. A- 4 & 5, Sector- 5 > G.B Nagar, Noida - 201301 > India > Tel .+91-120-2421651-660 Ext.211 > Fax.+91-120-2421691 > WWW.barco.com > mailto:[log in to unmask] > --------------------------------------------------- Technet Mail List provided as a service by IPC using LISTSERV 1.8e To unsubscribe, send a message to [log in to unmask] with following text in the BODY (NOT the subject field): SIGNOFF Technet To temporarily halt or (re-start) delivery of Technet send e-mail to [log in to unmask]: SET Technet NOMAIL or (MAIL) To receive ONE mailing per day of all the posts: send e-mail to [log in to unmask]: SET Technet Digest Search the archives of previous posts at: http://listserv.ipc.org/archives Please visit IPC web site http://www.ipc.org/contentpage.asp?Pageid=4.3.16 for additional information, or contact Keach Sasamori at [log in to unmask] or 847-509-9700 ext.5315 -----------------------------------------------------