Electronics Forum | Wed Jun 06 16:51:06 EDT 2001 | jax
Unless your placing micro-bga, board edge fiducials on alternating corners will provide more than enough placement correction ( Micro-bga's should also be fine depending on how your equipment maps the board ). The part data and vision recognition nee
Electronics Forum | Fri Jun 15 09:16:46 EDT 2001 | adam
Thanks Dave. About your second comment, the issue is placing BGA connectors mirror image (male, and female), the connector sometimes shifts during placement before reflow. we are using a six mil stencil for both sides with minimum paste deposit. a
Electronics Forum | Mon Jun 18 21:21:25 EDT 2001 | davef
Two things: 1 A flat surface will probably help the "balls on the socket sliding off the ridge of HASL" problem, but possibly consider less risky choices for your flat surfaces that immersion silver, like: OSP, ENIG, and immersion tin. 2 Don�t throw-
Electronics Forum | Mon Jun 25 11:26:36 EDT 2001 | wbu
What about conveyor speed? I tried to manage that the speed of the board and the speed of the wave were nearly the same at that point where the leads are leaving the wave. But actually I haven�t seen icycling except at one time and that was solved r
Electronics Forum | Mon Jul 09 14:03:39 EDT 2001 | ohboy
Make sure you're getting a good roll from your squeegies. Poly will "scoop", leaving less, nickel will add a little extra. A slightly shorter blade height out of the holders will help promote a good roll- this helps push the paste into the thru h
Electronics Forum | Mon Jul 02 06:01:22 EDT 2001 | wbu
Well, I�ve never encountered any problems with it. If you use paste in the specified window according time and environment there should be no problem. If you try to measure this force you would IMO check out if you yourself did not treat the paste as
Electronics Forum | Mon Jul 16 08:56:56 EDT 2001 | Hussman
Easy, DL says the customer is telling him after 5 reflow processes they get solder under the mask. He tried it and didn't see anything. DL needs more information to understand why and where this is occurring. So, if he can't duplicate the problem
Electronics Forum | Sat Jul 07 08:19:47 EDT 2001 | Stefan Witte
If your pads are raised as you mentioned, you will reach just the tip of your tiny glue dot, which may not hold the part in place. However, you should be using two glue dots on each side of your 0402 component. See under adherence force in paste a
Electronics Forum | Thu Jul 12 20:55:37 EDT 2001 | davef
First, we don�t like pallets, but ya gotta do wat ya gotta do!!! Second, we used to pallet after print and before place, but we lost so many prints messing with palleting boards that we now pallet, print, place. Third, most of our pallets are �home
Electronics Forum | Thu Jul 19 22:52:43 EDT 2001 | davef
Most paste manufacturers talk about a 12 month shelf life for paste. They give the user half of that time. The remainder is used-up in processing and distribution. We'd give it a shot. You paste supplier should be able to give you a much clearer
