Robert, I used Vapor Phase reflow with refined peanut oil from 1973 to about 1985. = I do know what I am talking about. That was long before lead free and Freon= was still used to clean the boards. At the time, there was no lead free process, so the solder paste was tin/le= ad eutectic (63/37) with a melting point of 183=B0C. Like you said, the smo= ke point of peanut oil is 232=B0C, so we were right in the process window o= f proper reflow, and as I said, it was critical to avoid fires, so we were = trying to keep the oil around 260=B0C, so the vapor where the board was goi= ng thru was around 240=B0C. That was long before fine pitch SMT (1206 chips= and SO IC packages were the norm). I never heard about oil bath soldering,so I have no clue about what you=92r= e talking about. But Vapor Phase is something I used a lot, and stopped to use as soon as IR= reflow was available. First I used straight IR (Vitronix 316), then convec= tion IR when it becomes available in the early 90=92s. Vitronix was a big s= upplier of IR ovens in late 80=92s early 90=92s, then competition drove the= m to be bought by someone else. =20 Jean-Paul AC9GH =20 > On Mar 22, 2015, at 4:30 PM, Robert Dvoracek wrote= : >=20 > Oil will smoke and break down before it boils. > The smoke point of peanut oil is 232=B0C and the flash point is 315.5=B0C= .. > That is too hot for reflow anyway. > I think this person is confused with oil bath soldering, which is a compl= etely different process. >=20 > Cheers, > Robert >=20 > ---------------------------------------- >> From: alan.b.pearce@stfc.ac.uk >> To: piclist@mit.edu >> Subject: RE: [EE] Do you solder using an inert gas ? >> Date: Sun, 22 Mar 2015 12:16:43 +0000 >>=20 >>> Denny, >>> I will disagree strongly with your first statement. Vapor Phase reflow = is far >>> from inert. It was used from the seventies to the late eighties, and wa= s using >>> boiling oil (peanuts oil) to create the vapor that melted the solder pa= ste. Was >>> very hard to control properly,and prone to fires, so not inert at all.. >>>=20 >>> Your last statement is correct. It was abandoned as soon as reflow oven= s >>> using first infra-red, and later convection IR were developed from mid >>> eighties on. >>=20 >> It has definitely not been abandoned, and using peanut oil ???? what the= heck is the boiling point of that ??? >>=20 >> It is highly successful if the correct liquid is used, which has a boili= ng point at the liquidus temperature of the solder, and it is a specialised= liquid for the purpose. >>=20 >> -- >> http://www.piclist.com/techref/piclist PIC/SX FAQ & list archive >> View/change your membership options at >> http://mailman.mit.edu/mailman/listinfo/piclist > =20 > --=20 > http://www.piclist.com/techref/piclist PIC/SX FAQ & list archive > View/change your membership options at > http://mailman.mit.edu/mailman/listinfo/piclist --=20 http://www.piclist.com/techref/piclist PIC/SX FAQ & list archive View/change your membership options at http://mailman.mit.edu/mailman/listinfo/piclist .