Electronics Forum | Fri Mar 21 09:08:53 EST 2003 | mantis
Hi all, I have a strange problem,while building a large 15x15inch 3.5mm thick Pcb.During topside reflow i am experiencing some misaligned parts and even bridging on a bga that are sitting very close to a D size tantalum cap.The strange thing is that
Electronics Forum | Fri May 07 12:39:01 EDT 2004 | rontdc
Bruce, Using a foam fluxer with no-clean flux is a very touchy situation. It is imperative that the specific gravity of any flux be maintained within the manufacturers recommendations. If it is not, you will get icicles and bridging. Maintaining the
Electronics Forum | Mon Feb 16 06:38:37 EST 2004 | Chris Lampron
Hi Carl, We have several Mirtec MV2BTLs. We had done an extensive evaluation on tabletop systems only, as we did not have the available real estate to add an inline. We are using the system to verify value (when visible) orientation, presence/absent
Electronics Forum | Wed Apr 14 08:15:18 EDT 2004 | arcandspark
We have tried other stencils with different size openings but this company will not allow us time or money to run any experiments to define stencil criteria and printer settings, its just run, run, run. They really dont care about post reflow yields.
Electronics Forum | Wed Apr 28 16:07:32 EDT 2004 | davef
In rework, your thermal recipe needs to better mimic the recipe that your use in your reflow oven. Oh, that and proper preheating of the board and BGA. [Yano, if you get bored fighting this, rereflowing the board is within reason.] That you are hi
Electronics Forum | Thu Nov 11 11:11:18 EST 2004 | clampron
D.B., You are justified in your concern over the last requirement. I have been imposed by a customer with the same hand solder/rework requirements. It seems the biggest concern is thermally shocking ceramic chips. You are much less likely to do this
Electronics Forum | Mon Feb 28 13:13:25 EST 2005 | russ
ING, you had to nake it difficult didn't ya! It appears that all of your parameters are okay. When you state that "sometimes there is a residue" is it liquidous or dry? Is your spray fluxer an ultrasonic or a spray gun head? You may not be getting
Electronics Forum | Sun Aug 14 22:58:17 EDT 2005 | crishan
Hi All, I would like help in establishing what is a feasible PPM reject rate from a typical SMD line. As a reference an SMD line consists of, solder paste printer, chip component placement, pick and place IC components and reflow. What is a bench
Electronics Forum | Tue Sep 06 09:20:50 EDT 2005 | Bob R.
We approached it the same way we select SnPb pastes. We started by doing coupon level tests to sort out the obvious "bad" pastes: SIR, wetting, solder balling, print quality, etc. That cut the field in half. From there we started to do assembly l
Electronics Forum | Thu Sep 08 01:58:08 EDT 2005 | darby
0. Any less and you are scooping the paste from the aperture with the squeegee blades. I'm not saying that either of these situations is a good or a bad thing, it's just that if you buy a 6 mil stencil, you are trying to achieve 6 mil paste height.