Electronics Forum | Tue Sep 11 09:13:01 EDT 2001 | davef
Like most things in electronic assembly, this is not astrophysics. People have pasted boards, placed components, turned the board up-side down, run the board through a reflow oven, and generalized about which components: * Fall off the board. * Don
Electronics Forum | Thu Jun 22 11:01:54 EDT 2000 | Chrys Shea
Jason, Double sided reflow should be no problem. People have been doing it for years. The surface tension of the molten solder will hold the components on the bottom side during your second pass. This is almost always the case, unless you have re
Electronics Forum | Thu Jun 22 11:02:13 EDT 2000 | Chrys Shea
Jason, Double sided reflow should be no problem. People have been doing it for years. The surface tension of the molten solder will hold the components on the bottom side during your second pass. This is almost always the case, unless you have re
Electronics Forum | Tue Sep 04 11:26:12 EDT 2001 | Jean Michel
During the solderin of a double side board, how can I calculate the maximum weight of a component I can put in the first side to avoid the component fall down in the oven (depending on the soler join surface) ? Are there some rules ?
Electronics Forum | Tue Feb 04 08:20:18 EST 2003 | roertner
This rule is very conservative depending on the epoxy you use and the subsequent handling of the board prior to reflow. You should use lead to pad contact area. Also be sure to look at part height and clearance on your flowsolder machine.
Electronics Forum | Tue Sep 04 18:11:18 EDT 2001 | davef
Assuming you're asking about double sided reflow soldering ... Use pad mating to lead wetting area. Bob Willis has found the ratio to be as much as 44 grams/sq in. Check Bob's site [Electronic Presentation Sevices] for more. Phil Zarro uses the
Electronics Forum | Mon Feb 03 18:37:28 EST 2003 | jonfox
Not to be off-topic, but push engineering for embedded passives and remove parts from the underside all together. Watch the material cost sky rocket, but watch the manufacturing cost sink and well as improve the production cycle by 50%. Sorry, I w
Electronics Forum | Mon Feb 03 18:00:49 EST 2003 | slthomas
I know that the accepted (by some, although some say it may be too conservative) rule is anything less than or equal to 30 grams/square inch of surface contact area should stay on the bottom side during the second pass. How is that surface area meas
Electronics Forum | Wed Jun 21 22:07:09 EDT 2000 | Jason
We are going to try double sided reflow for the first time. Can we use the same 63/37 paste on both sides? The board also has bare copper pads i'm pretty sure. will this present any challenges? The bottom side has a QFP on it. Should it stay on?
Electronics Forum | Thu Oct 19 12:34:36 EDT 2000 | lwatson
I can't seem to find an article about the limiting mass of a SMT component on the solderside of a double-sided reflowed PCB. I'm pretty sure that Phil Zarrow did an article on this subject. It went something like the mass/land surface area?
