Electronics Forum | Thu May 19 19:28:31 EDT 2011 | Rstadem
Try Easyspheres (Kester), or Q-Pearls (Qualitek), or Alpha. They all have solder spheres in that alloy.
Electronics Forum | Tue Apr 03 12:35:08 EDT 2012 | deanm
We have the same machine running the same alloy and have not seen this problem, but we're not running it nearly as much as you do. Have you asked Pillarhouse what could be happening? Try sending photos to them. They have been helpful in the past.
Electronics Forum | Tue May 14 21:40:23 EDT 2013 | ultimatejoker
What is the different between SAC and LF Solder Alloys?I found out that LF38 is SAC105 and LF45 is SAC305. Is it because LF is some standard international name for particular country?
Electronics Forum | Mon May 27 16:17:30 EDT 2013 | nikyta
Hi Eric, you have the right reduction on the stencils apertures? Also, a very oxidized solder paste can -and will do- promote and increase both the tombstoning as well as the solder balls.
Electronics Forum | Tue Mar 03 02:39:56 EST 2015 | sarason
I would presume you reflow the top of the board first. Use tented vias. As you have worked out, vias have surface tension, which sucks the solder up the hole during reflow of the bottom of the board. Good luck! regards sarason
Electronics Forum | Tue Mar 08 15:47:23 EST 2016 | sarason
Maybe your flux in the paste isn't working or simply isn't there in this new batch ? Heat a blob on the end of a soldering iron and smell it (head space analysis)(old chemist joke!) sarason
Electronics Forum | Fri Jun 07 10:46:16 EDT 2019 | gregoryyork
The Single Solder ball stuck to the mask may indicate undercured as well. The issue is not so much the mild No Clean flux but the potentially major active HASL flux or Silver Process chemistries causing issues. This has been through flow solder hasnt
Electronics Forum | Fri Jan 28 13:49:48 EST 2022 | jseewald
That is correct. This looks like a board that was printed then wiped but not washed. Solder spheres left out on an unsolderable surface will just sit there like this or coalesce into solder balls. Nothing in the picture indicates an issue with the
Electronics Forum | Mon Aug 14 05:45:16 EDT 2023 | dimamalin
First, this is the result of bad printer setup. Adjust knife pressure, PCB gap, separation speed, tooling, and stencil cleaning. Pay attention to the coating of contacts pad and height of solder mask of PCB.
Electronics Forum | Mon Aug 14 13:08:00 EDT 2023 | dimamalin
Similar issues arose for me in cases where the contact pads of components were located below the solder mask level. Ordering a thinner stencil might potentially solve the problem.
.gif)
