Electronics Forum | Tue Feb 11 10:47:02 EST 2020 | dunks
What paste do you use in this instance?
Electronics Forum | Fri Feb 07 20:41:52 EST 2020 | orbitcoms
I am finding if I have to stop the pick and place machine during production very often (mostly due to feeders not pulling the tape cover back), I get paste drying in the apertures of the stencil. To avoid this I am thinking of pasting all the boards
Electronics Forum | Thu Feb 27 12:41:21 EST 2020 | duke211
look at the specs of your solder and stencil life. Check the humidity, low humidity dries the paste. Slowing down your swipe speed and frequent wipe cleaning of your stencil can help.
Electronics Forum | Mon Feb 10 10:39:39 EST 2020 | slthomas
As has already been suggested, make sure you are cleaning your stencil well between long periods of inactivity. That said, it sounds to me like you have a feeder problem to solve before you get too wrapped up in what to do with your printing process
Electronics Forum | Mon Feb 10 11:51:53 EST 2020 | spoiltforchoice
... indeed, unless I'm very much mistaken you should be able to find refurbished or Chinese copies of your feeders in abundance on alibaba etc. I would suggest you try a few new ones as well as trying to refurbish the ones you have.
Electronics Forum | Fri Feb 28 03:59:41 EST 2020 | SMTA-Davandran
My input are: i. To solve tape not pulling back if it is due to high per is better to use more feeders to minimize this issue. ii. To slow down printing speed. Hence, has proper line balancing which minimize board idling before pick and place process
Electronics Forum | Mon Feb 10 10:23:53 EST 2020 | emeto
Solder paste has stencil life time - if you go over it means you should change it. If you print boards in front and keep them for too long before reflow, the flux is still evaporating, so you are not mitigating the risk. Paste also likes room tempera
Electronics Forum | Tue Feb 11 14:37:26 EST 2020 | spoiltforchoice
If you're asking me, I'm using BLT LFS-UFP-T4 (they have an even better paste to treat badly now if you add zq). Those in the test of the world might find Loctite GC10 is similar, however the stencil and tack times on the BLT are pretty awesome and
Electronics Forum | Sat Feb 08 04:37:19 EST 2020 | spoiltforchoice
I work with small batches and this is what I do. However I don't do it because of the paste. Instead I do it because I am the sole operator on the line and I want one process finished so I can keep a better eye on the others. I specifically work with
Electronics Forum | Fri Jul 29 10:03:02 EDT 2011 | blnorman
At a previous location we used the Semco cartridges. Occasionally the operator would have to scrape down the stencil and knead the paste back in. That would keep the paste on the edges from drying out. It was just standard procedure.
