Hi Hans Woweee!...what a load of gunk! I had similar experience with an old EPM machine a few years back. I emptied the solder pot, removed it, took of all the elements etc, then I took it outside and attacked it with shedloads of degreasant :-) Did the same for all the nozzle bits, pump shafts - the lot. Re-assembled (looking nice and shiny) and NEVER used tinning oil again! We only used oil around the pump shaft (little enclosure needed) Reduced the pot temp to reduce drossing, and used Kleenox powder for de-drossing - much better option than oil throughout. You have my sympathies! Good luck Justin Braime ------------------------ Process Engineer Compuspec Industries Ltd Auckland, New Zealand ----- Original Message ----- From: Hinners Hans Civ WRALC/LYPME To: [log in to unmask] Sent: Wednesday, August 23, 2000 7:31 AM Subject: [TN] Wave Flow Solder Problem Hi Everybody, I've been asked to troubleshoot a BIG problem with our wave flow soldering machine and I could use some advice. I'm in the beginning stages of learning about wave flow soldering. We use Tin Lead 63/37 solder with Kester-5738 Dross Inhibiting Oil and, to date, my solder analysis has come back fine. And recently, we've been getting alot of bridging on assemblies (multilayer FR-4). No surprise really, there is an embarrassing amount of scum (dross-?) and our Tinning oil is gunking up. We've only used this oil for a few months so it's the only reported process change. The joints look It's an old Hollis machine (bought in '83) that has seen better days. The first thing management said was, "Should we go and buy a new machine?" Showed Kester the pics and they said the oil was at the end of its life and broke down. I threw a couple of pictures on my public drive starting with the word 'Solder -'. I kept them fairly large (~500 k each) so people can get a good idea of what I'm up against. For the digital buffs, they're scaled down 60% from the originals using a Sony DSC-D700 camera. http://www.driveway.com/share?sid=a8f3cb1d.96df8&name=Pictures Thoughts, questions, suggestions, . . . . prayers? Do we just need to scoop the gunk out (that was my weekend) and keep going? Start over with a fresh bath of solder? The more I do, the more I learn . . . the hard way. Hans ~~~~~~~~~~~~~~~~~~~ Hans M. Hinners Materials Engineer (Process & Manufacturing) Warner Robins Air Logistics Center Avionics Production Division Manufacturing Branch 380 Second Street, Suite 104 Building: 640, Mail Stop: LYPME Robins AFB, GA 31098-1638 Voice: (478) 926 - 1970 Fax: (478) 926 - 7164 mailto:[log in to unmask] http://www.robins.af.mil