Electronics Forum | Tue Mar 01 11:11:50 EST 2005 | spot
We use SRT. We still have machines that are over 5 years old and are functioning very well in the BGA, QFP and yes CSP area. The critical part is getting the right Air nozzle for the part size. Also the software has a auto-profile feature that wor
Electronics Forum | Mon Mar 07 08:53:59 EST 2005 | Marc
some thoughts come to mind..... usually an air pocket as the solder heats up, or the surface is still solid and liquid under, pressure builds and then... check your heaters, make sure one (or more) is not bad, may be getting uneven heating. cover y
Electronics Forum | Thu Mar 17 11:07:08 EST 2005 | Dougs
I'd agree with Justin, we do double sided reflow on most of our boards with fine pitch QFP's both sides, you do have a problem somewhere else, what size is you board? Is it warping slightly? What kind of oven are you using? Is it convection? fans
Electronics Forum | Thu Apr 14 05:23:10 EDT 2005 | dj_jago
What is the pitch of the device and what type of flux are you using? You may eridicate the fault by using a more active flux. I assume you are flowsoldering the device as opposed to paste in hole. Do you have an air knife? If so, you could tr
Electronics Forum | Wed May 04 15:34:38 EDT 2005 | mmjm_1099
I worked at a place where they homemade a parts humidoor. What they did was take some plexiglass get it cut to the measurments they needed. Than they assembled it and added air control to it to keep the humidity set. Damn if I can remember exactly wh
Electronics Forum | Tue May 31 11:43:27 EDT 2005 | ??
Worn out is all relative. If the machine is in a factory on a dirt floor with no air-conditioning.....it could be "worn out" after 1000 hrs. but then again....if it is in a well kept building with the proper maintenence........10000 hrs could be fine
Electronics Forum | Thu Jun 09 19:09:37 EDT 2005 | Kantesh Doss
We verify oven profiling once a week on a scrap board and enter the data in a SPC Chart. This works out great and I have not noticed any problem. I also like the idea of sending the Profiler through the oven with the thermocouple sticking out to meas
Electronics Forum | Thu Jun 23 10:36:04 EDT 2005 | stepheniii
I think the single most important thing will be to maintain positive pressure in the room. All the air filtering will not be able to keep up if dirt is blown into the room everytime a door is opened. The next would be to control as much as possible,
Electronics Forum | Thu Jun 23 10:49:46 EDT 2005 | slthomas
Your HVAC contractor is probably the guy to talk to (they can hook you up with a variety of air handling and filtration systems depending on the level of cleanliness you want). Another thing you can do is reduce the amount of dust you bring in and/
Electronics Forum | Wed Jun 29 18:11:13 EDT 2005 | GS
Start from this: - check the air flow speed, if too much it can help to get components moved/blowed away. - Other cause (not so often)it could be moisture in PCB, so when degassing, may be trough vias, the pressure could blow away components. Regar
