Steve: We also run an Electrovert Electra. We use Alpha's 871-25 OA flux, similar to your 2331 which we have also used, applied by foam fluxing. Looking at your photos it's hard to tell but the "Dross Particles" appear more like solder webbing than dross and the "More Dross" does look like dross. I'm discounting a problem with the soldermask cure or board design because you say it's happening with all your boards. However you may want to verify soldermask cure as a sanity check. 1. My first guess is that you are drying out the flux on the board. The flux no longer can act as a lubricant/thermal insulator and the solder and dross stick to the board surface. Obviously insufficient flux deposition, excessive preheat, slow conveyor speed can all contribute. Is it re-occurring in a given band or area where there may be lack of flux or a hot spot in the preheaters? If item 1 is not the case consider the following: 2. Are you running the chipwave? This can be a large generator of dross. We clean both the chip and Lambda wave pots of dross every two hours. 3. Is the overflow on the Lambda wave set correctly? If not you will not get the proper overflow and dross will build in the wave. 4. How often do you remove and clean the chipwave and Lambda nozzles? We remove and clean every 80 hrs of operation. These have a tendency to build up dross which comes up thru the wave. 5. How often do you teardown the entire solderpot and pull everything out for a complete cleaning? We do a complete teardown every 1000 hrs. You would be amazed at how much dross and residue is built up inside the pot and it's internal components. Regards Michael Barmuta Staff Engineer Fluke Corp. Everett WA 425-446-6076 Regards -----Original Message----- From: Steve Gregory [mailto:[log in to unmask]] Sent: Thursday, October 10, 2002 6:58 AM To: [log in to unmask] Subject: [TN] Dross particles sticking to soldermask... Mornin' all, I've got a problem here that's giving me a little headache. As you may know, we got a new wave solder machine not too long ago, an Electrovert Electra. For the past couple of weeks we've had a problem with dross particles sticking to the soldermask. It's happening across all our boards, whether or not we use an OA flux or RMA. Go to: http://www.stevezeva.homestead.com and look at Dross Particles, and More Dross. As you can see, it's not that bad, but it's irritating. The particles don't want to come off without mechanically brushing the board either, and again it doesn't matter if it's OA flux or RMA. If we run them through our cleaners without brushing the boards, the particles will remain. Our pot is clean, it's de-drossed every morning. We're using Kester 2331ZX OA, and Alpha 16-125 RMA. It's being applied by a OptiFlux ultrasonic spray fluxer. The boards look great coming out of wave except for these random bits of dross sticking to the mask. Solder joints look great, no dross in them at all...just sticking to the mask. Got me kind of puzzled...anybody ever have this happen to them? Thanks! -Steve Gregory- ---------------------------------------------------------------------------- ----- Technet Mail List provided as a free 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/html/forum.htm for additional information, or contact Keach Sasamori at [log in to unmask] or 847-509-9700 ext.5315 ---------------------------------------------------------------------------- ----- --------------------------------------------------------------------------------- Technet Mail List provided as a free 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/html/forum.htm for additional information, or contact Keach Sasamori at [log in to unmask] or 847-509-9700 ext.5315 ---------------------------------------------------------------------------------