Electronics Forum | Mon May 24 13:33:46 EDT 1999 | Dave F
| We are running a number of boards with 8-10 25 mil PQFPs on board. Our process is mature with at least 3 years experiance and statistically few opens on the QFPs. Our beloved purchasing department has chased the almighty $ and changed FAB vendor
Electronics Forum | Wed Mar 14 07:30:14 EDT 2007 | davef
So, you toss whatever is on the stencil every 8 hours. Correct? How long has it been on the stencil? * If that particular paste has been on the stencil for 8 hours, we'd agree to toss it too. * If paste has been on the stencil for less than 8 hour
Electronics Forum | Tue Sep 18 19:32:49 EDT 2007 | davef
Welcome Jimmy Let's mince words to help focus on the issues. When you say "QFP area solder paste shifted," do you mean: * Paste printed on land pattern perfectly, but moves after printing. * Paste printed off the land pattern, even though the stenci
Electronics Forum | Mon Mar 05 12:52:06 EST 2007 | DC
Any one have experience of MyData paste jet printing? I don't ave chance to take a look at Apex but it can reduce the paste, no stencil required and paste volume control by programming.
Electronics Forum | Mon Mar 27 22:20:04 EST 2006 | davef
Mike The air 'contained' in the aperture would prefer to escape between the board and the bottom of the stencil rather than through your paste while you're printing over it.
Electronics Forum | Tue Mar 06 09:01:17 EST 2007 | Rob
Yes, looks great - had a play at one of their roadshows. Could turn into an amazing product if they can scale it down enough. However, it's slow and costs more than a large house. More than a screen printer and a huge number of stencils.
Electronics Forum | Sun Jan 07 08:46:08 EST 2018 | spoiltforchoice
Your paste should specify a number of times it is OK for various things to happen. The two you might care about are the "Stencil Time"/"Working life", which is how long the paste can be out of the pot on your stencil while you print PCBs. The othe
Electronics Forum | Wed Sep 19 21:04:57 EDT 2007 | wailiang81
Hi,davef, thanks for your concern. The condition was the pasted printed off with around 0.8~0.9mm from the land pattern. This will easy observe at QFP area. At fiducial, the stencil seens aligned accurately. Once solder bridge happend, its easy to
Electronics Forum | Fri Sep 21 10:31:44 EDT 2007 | russ
this would be meaniung that somewhere in your documantation it should have spec called "repeatability" what this means is that when the vision aligns the stencil/board, the board will always be within "x" amount of the njominal xy "T" position, some
Electronics Forum | Sun May 23 15:12:59 EDT 1999 | JohnW
| We are running a number of boards with 8-10 25 mil PQFPs on board. Our process is mature with at least 3 years experiance and statistically few opens on the QFPs. Our beloved purchasing department has chased the almighty $ and changed FAB vendor
