Electronics Forum | Fri Feb 24 08:29:25 EST 2006 | davef
Step stencils are not widely used, due to: * Higher cost as compared to uniform thickness stencils * Danger of solder paste smearing at least close to the steps * Difficulty of cleaning the stepped stencil underside (the steps cannot be on the upper
Electronics Forum | Fri Dec 10 02:26:16 EST 1999 | Tracy Guo
Hi, I'm facing smear after printing on DEK288 using reverse squeegee at the edge of panels. I've checked the fixture, printing parameter, stencil, solder paste. What else can I do?
Electronics Forum | Sat Oct 08 12:42:10 EDT 2016 | ttheis
Well I stand corrected; we tried re-printing mis-prints on Friday with our auto printer and indeed it worked out very well. I did let the paste dry up a bit on the mis-printed board while a few others went through to try and prevent smearing as it re
Electronics Forum | Wed Mar 21 16:32:03 EST 2001 | mparker
The root cause is dependant on the type of solder "splash", ball, whatever, that you are seeing post reflow. If it is smears, then cleaning the stencil underside is probably the answer. Are you using automatic wipers? How many print cycles between w
Electronics Forum | Tue Nov 07 10:09:51 EST 2000 | Kevin
John, Depends on what you're cleaning (paste, adhesive, ink, etc..) and your process (do operators just dump a dirty stencil in and expect a clean one out, drying time, effect on the polyester). I could suggest a couple of name brand cleaners, but I
Electronics Forum | Fri Sep 30 03:36:39 EDT 2005 | pavel_murtishev
Good day, 2D inspection requires correct adjustment. In the other case it will cause continuous problems and false alarms. Adjust the lightning first and choose the correct process limits second. Look at histogram when you are adjusting the camera
Electronics Forum | Mon Jan 19 20:01:11 EST 1998 | Steve Gregory
| We use no clean paste and sometimes experience | flux splattering which gives spot on gold fingers. | Need help in analize the cause. thx. Dominic, That is STILL a problem huh? It's a tough one to solve sometimes...especially when you have as
Electronics Forum | Wed Aug 22 11:58:11 EDT 2007 | ev
Thanks for all responses really good feedback. I have placed a number of extra supports underneath each pcb in the panel and by checking each print diligently we seem to be able to keep running. Not feaseable at the moment to check out leaded paste o
Electronics Forum | Mon Nov 26 10:08:56 EST 2007 | kevslatvin
I have been using it and noticed it seems to get runny after it has been out on the stencil awhile. Couple hours or so. At that point we've had some problems with the paste smearing on some fine pitch stuff(0.020"). I sped up my squeegee speed and it
Electronics Forum | Tue Sep 23 07:27:31 EDT 2008 | realchunks
Do not wipe the board at first before putting it in your cleaner. It will leave more paste in your tank, but you won't smear it into every corner of your solder resist. We found that only our stencil cleaner would clean a board properly and leave n
