Electronics Forum | Fri Feb 19 14:43:46 EST 1999 | Nithy
We are in the process of getting into no-clean paste and fluxes. One important issue in this is sodler balling. I have heard some people say that having a matte finish would help in having lesser solder balls and that the solder balls would not be
Electronics Forum | Tue Aug 09 10:38:45 EDT 2005 | SuMoTe
Water soluable dots will wash off after reflow. A water soluable liquid mask will work as well. dots are better for defined (round)holes, whereas the liquid mask works well with odd shapes.
Electronics Forum | Tue Aug 09 11:56:01 EDT 2005 | Rob
We sometimes use a peelable mask the the PCB manufacturer (board house) adds as part of their process. It may seem an expensive option but avoids: Raising P/o's for tape/peelable mask as consumables booking & inspection Booking out to the shop floo
Electronics Forum | Sat Feb 20 09:56:22 EST 1999 | Tufty
| We are in the process of getting into no-clean paste and fluxes. One important issue in this is sodler balling. I have heard some people say that having a matte finish would help in having lesser solder balls and that the solder balls would not b
Electronics Forum | Thu Aug 18 13:11:39 EDT 2005 | jsloot
We have our board house apply a peel coat mask that can be brushed off after wave or reflow. You need to brush off while it's still warm.
Electronics Forum | Wed Aug 10 11:57:16 EDT 2005 | pr
Is the peelable mask (put on by the boardhouse) flat on the surface of the pcb? If so can you tell me the material name, so maybe I can find a picture? We have to print adhesive on the board, so the mask has to be flat. That is why Kapton from the b
Electronics Forum | Tue Aug 09 13:25:24 EDT 2005 | pr
From what I can gather, the annular rings are used for grounding when these boards are put in housings. A screw goes through the hole and is torqued down. If there is excess solder on the annular ring, the screw doesn't seat properly. The pallets cov
Electronics Forum | Tue Aug 09 12:12:57 EDT 2005 | davef
Why are you placing Kapton dots on your board prior to wave soldering? * Prevent solder from touching the hole and the area around it. [If so, why do you need to do this?] * Prevent solder from flowing up through the hole and coating portions of the
Electronics Forum | Tue Aug 09 13:51:03 EDT 2005 | patrickbruneel
You can also insert a stainless steel screw the size of the hole in the board before wave soldering, this will prevent the solder from wicking up to the top or close the hole (this is real cheap). I still remember the good old days using toothpicks t
Electronics Forum | Wed Aug 10 15:09:06 EDT 2005 | pr
O.K. thanks, I'll look into it............through a rep, since all our boardhouses are in China/Taiwan. I'm seeing a pattern! thanks, pr
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